the determinants of antiretroviral therapy adherence and

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University of South Florida Scholar Commons Graduate eses and Dissertations Graduate School January 2013 e Determinants of Antiretroviral erapy Adherence and the Relationship of Healthcare Expenditures to Adherence among Florida Medicaid-insured Patients Diagnosed with HIV or AIDS Zachary Prui University of South Florida, [email protected] Follow this and additional works at: hp://scholarcommons.usf.edu/etd Part of the Medicine and Health Sciences Commons is Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate eses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Scholar Commons Citation Prui, Zachary, "e Determinants of Antiretroviral erapy Adherence and the Relationship of Healthcare Expenditures to Adherence among Florida Medicaid-insured Patients Diagnosed with HIV or AIDS" (2013). Graduate eses and Dissertations. hp://scholarcommons.usf.edu/etd/4834

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Page 1: The Determinants of Antiretroviral Therapy Adherence and

University of South FloridaScholar Commons

Graduate Theses and Dissertations Graduate School

January 2013

The Determinants of Antiretroviral TherapyAdherence and the Relationship of HealthcareExpenditures to Adherence among FloridaMedicaid-insured Patients Diagnosed with HIV orAIDSZachary PruittUniversity of South Florida, [email protected]

Follow this and additional works at: http://scholarcommons.usf.edu/etd

Part of the Medicine and Health Sciences Commons

This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion inGraduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please [email protected].

Scholar Commons CitationPruitt, Zachary, "The Determinants of Antiretroviral Therapy Adherence and the Relationship of Healthcare Expenditures toAdherence among Florida Medicaid-insured Patients Diagnosed with HIV or AIDS" (2013). Graduate Theses and Dissertations.http://scholarcommons.usf.edu/etd/4834

Page 2: The Determinants of Antiretroviral Therapy Adherence and

The Determinants of Antiretroviral Therapy Adherence and

the Relationship of Healthcare Expenditures to Adherence among

Florida Medicaid-insured Patients Diagnosed with HIV or AIDS

by

Zachary Pruitt

A dissertation submitted in partial fulfillment of the requirements for the degree of

Doctor of Philosophy Department of Health Policy and Management

College of Public Health University of South Florida

Major Professor: Barbara Langland Orban, Ph.D. Robert G. Brooks, M.D.

Sheri L. Eisert, Ph.D. John T. Large, Ph.D. John Robst, Ph.D.

Date of Approval: November 2013

Keywords: chronic disease, managed care, health, quality, care management

Copyright © 2013, Zachary Pruitt

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Table of Contents

List of Tables ..................................................................................................................... iii List of Figures .................................................................................................................... vi Abstract ............................................................................................................................. vii Chapter One: Introduction / Statement of the Problem ...................................................... 1 Chapter Two: Review of the Literature .............................................................................. 5

ART adherence ....................................................................................................... 5 Key factors associated with ART adherence .......................................................... 7 ART adherence association with total healthcare expenditures ........................... 10 Antiretroviral therapy background ........................................................................ 15 Healthcare expenditures ........................................................................................ 18 Inpatient utilization ............................................................................................... 19 Comorbidities among PLWHA............................................................................. 21 Florida Medicaid and HIV/AIDS .......................................................................... 23

Chapter Three: Methods ................................................................................................... 26

Data…………… ................................................................................................... 26 Sampling methods and inclusion criteria .............................................................. 26 Calculating healthcare expenditures ..................................................................... 29 Missing data due to lapses in Medicaid coverage ................................................. 29 Descriptive statistics ............................................................................................. 30 Inferential statistical analysis ................................................................................ 31 Objective 1: Overview .......................................................................................... 31 Objective 1: Hypotheses ....................................................................................... 31 Objective 1: Determinants of ART non-adherence .............................................. 32 Objective 1: Expectations ..................................................................................... 37 Objective 2: Overview .......................................................................................... 38 Objective 2: Hypothesis ........................................................................................ 38 Objective 2: Model variables ................................................................................ 40 Objective 2: Expectations ..................................................................................... 42

Chapter Four: Results ....................................................................................................... 43

Final inclusion and exclusion criteria ................................................................... 43 Data cleaning ........................................................................................................ 46

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Objective 1: Descriptive results ............................................................................ 50 Objective 1: Unadjusted logistic regression results .............................................. 62 Objective 1: Model diagnostics ............................................................................ 65 Objective 1: Logistic model results ...................................................................... 67

Objective 1 full model. ............................................................................. 67 Objective 1 reduced model. ...................................................................... 70

Objective 2: Descriptive results ............................................................................ 72 Objective 2: Model diagnostics ............................................................................ 79 Objective 2: Model results .................................................................................... 81

Objective 2 multivariate regression HIV model. ...................................... 81 Objective 2 multivariate regression AIDS model. .................................... 84

Chapter Five: Conclusions and Recommendations .......................................................... 87

Objective 1: Discussion ........................................................................................ 87 Objective 1: Recommendations ............................................................................ 93 Objective 1: Future research ................................................................................. 95 Objective 1: Limitations ....................................................................................... 95 Objective 1: Conclusion ........................................................................................ 97 Objective 2: Discussion ........................................................................................ 98 Objective 2: Recommendations .......................................................................... 102 Objective 2: Future research ............................................................................... 104 Objective 2: Limitations ..................................................................................... 105 Objective 2: Conclusion ...................................................................................... 106

List of References ........................................................................................................... 108 Appendices ...................................................................................................................... 127

Appendix A: HIV/AIDS Pharmaceutical National Drug Codes......................... 128 Appendix B: CPT Codes used to identify HIV/AIDS ........................................ 147 Appendix C: International Classification of Diseases, Ninth Revision, Clinical

Modification codes used to identify HIV/AIDS ..................................... 148 Appendix D: Florida county median household income, rural or urban

designation, and Agency for Health Care Administration county codes 150 Appendix E: Depression, anxiety or somatoform diagnoses, alcohol abuse and/or

substance abuse, or severe mental illness diagnoses .............................. 152 Appendix F: Expenditure-predictive diagnosis groups and key comorbidities .. 157 Appendix G: Institutional Review Board Approvals .......................................... 160

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List of Tables TABLE 2.1: FDA approved generic antiretroviral drugs ................................................. 17

TABLE 3.1: Analysis variables ........................................................................................ 28

TABLE 3.2: Objective 1 model variables......................................................................... 33

TABLE 3.3: Objective 2 model variables......................................................................... 40

TABLE 4.1: Descriptive statistics for monthly laboratory expenditures in 24 month measurement period (n=435) ................................................................................ 48

TABLE 4.2: Descriptive statistics for monthly laboratory expenditures for subjects averaging greater than $0 in 24 month measurement period (n=249) .................. 48

TABLE 4.3: Descriptive statistics for Medicaid-insured previously ART-naïve PLWHA whose ART includes generic medications (n=5) .................................................. 49

TABLE 4.4: Descriptive statistics for medication possession ratio among Medicaid-insured PLWHA whose ART included generic medications (n=5) ...................... 49

TABLE 4.5: Descriptive statistics for total healthcare expenditure among PLWHA whose ART included generic medications (n=5) ............................................................. 49

TABLE 4.6: Frequency of previously ART-naïve Medicaid-insured PLWHA in antiretroviral therapy "adherence" and "non-adherence" categories as measured by possession ratio (MPR) in 24 month measurement period (n=514) ..................... 50

TABLE 4.7: Descriptive statistics for Medicaid-insured medication naïve PLWHA by adherence and non-adherence categories (n=514) ................................................ 51

TABLE 4.8: Descriptive statistics for age in reference year (n=514) .............................. 51

TABLE 4.9: Medication possession ratio (MPR) among previously ART-naïve Medicaid-insured PLWHA by age groups (n=514) .............................................................. 52

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TABLE 4.10: Adherent (>90%) and non-adherent (<90%) proportions by race/ethnicity for Medicaid-insured previously antiretroviral naïve PLWHA (n=514) .............. 53

TABLE 4.11: Medication possession ratio (MPR) by race and ethnicity for Medicaid-insured previously antiretroviral naïve PLWHA (n=514) .................................... 53

TABLE 4.12: Medication possession ratio (MPR) by Medicaid eligibility category for PLWHA (n=514) .................................................................................................. 54

TABLE 4.13: Medicaid eligibility categories by type and adherence category among previously ART-naïve Medicaid-insured PLWHA (n=514) ................................ 55

TABLE 4.14: Frequency and distribution of MPR by county population density for Medicaid-insured previously ART naïve PLWHA (n=514) ................................. 56

TABLE 4.15: Frequency and distribution of medication possession ratio (MPR) by county median household income category for Medicaid-insured PLWHA (n=514) .................................................................................................................. 56

TABLE 4.16: Frequency of subjects residing in counties by median income (high versus low) and population density (urban versus rural) attributes (n=514) ................... 56

TABLE 4.17: Proportion of HIV or AIDS disease status by adherence and non-adherence categories for Medicaid-insured previously ART naïve PLWHA (n=514) .......... 58

TABLE 4.18: Medication possession ratio (MPR) by HIV or AIDS disease status for Medicaid-insured previously ART naïve PLWHA (n=514) ................................. 58

TABLE 4.19: Total and proportion of outpatient visits in 24 month measurement period among Medicaid-insured previously ART-naïve PLWHA (n=514) .................... 59

TABLE 4.20: Number of concurrent ARV medications filled in the first month of ART initiation by HIV or AIDS status among previously ART-naïve Medicaid-insured PLWHA (n=514) .................................................................................................. 60

TABLE 4.21: ART-related adverse drug reactions among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514) ........................... 61

TABLE 4.22: Chronic diseases among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514) ........................................................... 62

TABLE 4.23: Descriptive statistics for Medicaid-insured previously antiretroviral-naïve PLWHA by non-adherent (<90%) and adherent (>90%) categories (n=514) ...... 63

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TABLE 4.24: Full logistic regression model of non-adherence (<90% MPR) to ART among previously ART-naïve Medicaid-insured PLWHA (n=514) .................... 68

TABLE 4.25: Reduced logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514) (n=514) .................................................................................................... 70

TABLE 4.26: Proportion of HIV or AIDS disease status by adherence and non-adherence categories for Medicaid-insured previously ART naïve PLWHA (n=502) .......... 72

TABLE 4.28: Monthly expenditures by category for HIV-positive subjects by adherence category (n=232) ................................................................................................... 75

TABLE 4.29: Monthly expenditures by category for AIDS-diagnosed subjects by adherence category (n=270) .................................................................................. 76

TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232) .................................. 76

TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232) .................................. 77

TABLE 4.31: Descriptive statistics for AIDS-diagnosed Medicaid-insured subjects by ART medication possession ratio adherence categories (n=270) ......................... 77

TABLE 4.32: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve HIV-positive subjects (n=232) .................................................................... 82

TABLE 4.33: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve AIDS-diagnosed subjects (n=270) .............................................................. 85

TABLE A1: HIV/AIDS Pharmaceutical National Drug Codes ..................................... 128

TABLE A2: Current Procedural Terminology Codes used to identify HIV/AIDS ........ 147

TABLE A3: International Classification of Diseases, Ninth Revision, Clinical Modification codes used to identify HIV/AIDS ................................................. 148

TABLE A4: Florida county median household income, rural or urban designation, and Agency for Health Care Administration county codes ....................................... 150

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TABLE A5: Depression, anxiety or somatoform diagnoses (DEP_ANX), alcohol abuse and/or substance abuse (AASA), or severe mental illness (SMI) diagnoses ...... 152

TABLE A6: Expenditure-predictive diagnosis groups and key comorbidities among previously ART naïve Medicaid-insured PLWHA (n=502) ............................... 157

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List of Figures

Figure 4.1: Frequency of Subjects from Antiretroviral Initiation Month to End of Study in Twenty-Four Month Measurement Period (n=514) .............................................. 44

Figure 4.2: First month of ART (n=514) .......................................................................... 46 Figure 4.3: Project AIDS Care enrollment or case management services claims by year 47 Figure 4.4: ART Adherence category by race/ethnicity (n=514) ..................................... 52 Figure 4.5: Frequency of subjects residing in counties by median income and population

density ................................................................................................................... 57 Figure 4.6: HIV or AIDS disease status by ART adherence ............................................ 57 Figure 4.7: Model fit chart of deviance residual ............................................................... 66 Figure 4.8: Unadjusted mean monthly total healthcare expenditures by ART adherence

category ................................................................................................................. 73 Figure 4.9: Unadjusted mean monthly total healthcare expenditures by HIV/AIDS status

by ART adherence category .................................................................................. 74 Figure 4.10: Unadjusted mean monthly total healthcare expenditures by ART adherence

category ................................................................................................................. 75 Figure 4.11: Non-normal distribution of total healthcare expenditure for the HIV-positive

group ..................................................................................................................... 79 Figure 4.12: Predicted residuals ........................................................................................ 81 Figure 4.13: HIV-positive model adjusted mean total healthcare expenditures (n=232) . 84

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Abstract

Research supports the clinical and societal benefits of antiretroviral treatment

(ART) for people living with HIV or AIDS (PLWHA). However, factors associated with

ART adherence and the relationship of ART adherence to total healthcare expenditures

are not well understood.

The research data included Florida Medicaid claims for five years (July 2006

through June 2011). All subjects (n=514) were HIV-positive, adult, non-pregnant, and

ART naïve for at least 12 months prior to their 24 month measurement period. Each

subject was categorized as adherent (>90%) or non-adherent (<90%) based upon

medication possession ratios (MPR). Total expenditures were payments Medicaid made

to providers and pharmacies.

Objective 1 modeled the logit probability of a subject being non-adherent to ART

(versus adherent). Certain factors were expected to have significant negative associations

with non-adherence to ART, including females, older age group, AIDS diagnosis,

adherence to antidepressants, severe mental illness, meeting the minimum recommended

number of outpatient visits, ART regimen type, number of medications in the ART

regimen, residing in a county with a high median income, and residing in a county with

an urban population density. The variables expected to have significant positive

associations included race/ethnicity, substance or alcohol abuse diagnosis, depression or

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anxiety diagnoses, disease progression from HIV to AIDS, discontinuous Medicaid

coverage, Medicaid eligibility type, and co-morbidity count levels.

The Objective 1 results showed that all non-white race/ethnicity categories had at

least twice the odds of being classified as non-adherent. Also, increasing numbers of

concurrent ART medications significantly predicted non-adherence; the odds ratio for

three to five ART medications was 2.04 (95% CI=1.04-4.01, p<.05), and six or more

prescriptions category odds ratio was 4.58 (95% CI=1.82-11.56, p<.01), as compared to a

single medication. Finally, a chronic diseases diagnosis was protective against non-

adherence (OR=.46, 95% CI=.26-.84, p<.01), as was adherence to antidepressants

(OR=.28, 95% CI=.14-.54, p<.01).

In Objective 2, it was expected that the ART adherence group, the explanatory

variable, would have significantly less monthly mean total healthcare expenditures, the

outcome variable. For each of the HIV-positive (n=232) and the AIDS-diagnosed

(n=270) groups, a generalized linear model predicted the mean total expenditures for the

ART non-adherence group (<90% MPR) versus the ART adherence group, controlling

for other factors. For the HIV-positive subjects, the predicted mean total healthcare

expenditures for the ART non-adherent group was $1,291 (95% CL $840-$2,004); the

predicted mean for the adherent group was $1,926 (95% CL $1,157-$3,231). The

difference was statistically significant, but the hypothesis was not supported. The non-

adherent group mean was less than the adherent group (-40%, p<.001). However, for the

AIDS-diagnosed subjects, there was no statistical difference between the non-adherent

and adherent groups. The predicted mean for the non-adherent group was $2,279 (95%

CL $1,572-$3,322), and $2,005 (95% CL $1,387-$2,913) for the adherent group.

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The findings of this research support the need for translating evidence on

racial/ethnic disparities in ART adherence, along with behavioral, social, or cultural

barriers and effective interventions, into policy and practice. Also, certain medication

management strategies should be implemented to reduce the number of medications in

ART regimen. Finally, the results of the present study underscores the necessity for

appropriate financial incentives and purposeful risk-adjusted capitation payment

structures that would support ART adherence among Medicaid-insured PLWHA.

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Chapter One: Introduction / Statement of the Problem

Antiretroviral medication therapy (ART) has transformed HIV/AIDS from an

acute infectious disease with high mortality to a manageable chronic disease for which

treatment adherence is vital (Dieffenbach & Fauci, 2011). Current research provides

overwhelming support for the clinical and societal benefit of ART for certain people

living with HIV or AIDS (PLWHA), as it reduces their viral load and decreases their HIV

transmission risk (Reynolds et al., 2011). Unfortunately, below optimal adherence to

ART predicts increased morbidity and mortality (Hogg et al., 2002; Lieb et al., 2002) and

virologic failure (Maggiolo et al., 2005).

However, the factors associated with ART adherence are not well understood. In

spite of a plethora of published studies examining the factors associated with adherence

to ART, only a small number of determinants are reliably statistically significant across

studies (Reynolds, 2004). The key correlates most consistently associated with non-

adherence to ART are psychosocial variables, such as low patient self-efficacy, life stress

or lack of social support and antiretroviral treatment-related factors, such as side-effects,

inconvenience or regimen complexity (Ammassari et al., 2002). On the other hand,

demographic factors (e.g., race and income), patient education interventions, psychiatric

comorbidities (e.g., alcohol abuse, depression), patient-provider relationships are not

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reliably associated with ART adherence. This research will examine determinants

associated with ART non-adherence for PLWHA with Medicaid coverage.

Despite agreements on clinical benefits to treatment, ambiguity surrounds cost

savings related to ART adherence. Bozzette et al. (2001) and Nachega (2010) found that

ART adherence was independently related to a reduction in healthcare expenditures,

while Gardner et al. (2008) and Acurcio et al. (2006) found that improved adherence to

ART was associated with an increase in total medical expenditures. These conflicting

results represent a research opportunity for the present study.

Inconsistent results such as these influence a broader debate of whether adherence

to recommended care for chronic diseases is associated with decreased expenditures.

Adding to the chronic disease care cost concern, medication adherence seems to have

contradictory influences on costs for different diseases. For example, evidence shows that

adherence to antidepressant medication is significantly related to increased near-term

future costs (6 months following initiation) (Robinson et al., 2006). Similarly, children

enrolled in Medicaid that were adherent to asthma medications incurred higher

expenditures, despite having lower non-drug expenditures (Mattke, Boylston Herndon,

Cuellar, Hong, & Shenkman, 2010). It has been postulated that the positive relationship

of chronic disease medication adherence to increased costs may be due to improved

access to needed services (Riegel, 2000).

However, other chronic diseases show the opposite association of medication

adherence to costs. Medicaid expenditures decreased for congestive heart failure patients

who are adherent to their medication treatment (Esposito, Bagchi, Verdier, Bencio, &

Kim, 2009). Also, Roebuck et al. (2011) found total savings associated to medication

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adherence for conditions such as certain vascular conditions, congestive heart failure,

hypertension, diabetes, and dyslipidemia were due to decreased inpatient costs, relative to

the medication expenditures. Earlier cost studies regarding diabetes, hypertension, and

high cholesterol all showed lower total medical costs were linked to higher condition-

specific medication adherence (Sokol, McGuigan, Verbrugge, & Epstein, 2005). These

authors (2005) observed that savings were primarily due to the cumulative effects of

sustained adherence over several years. Thus, it is unclear that efforts to assure adherence

to recommended care for chronic diseases reduces total healthcare expenditures,

especially in the near-term.

The relationship of ART adherence to healthcare expenditures has current policy

significance in Florida. In early 2011, Governor Rick Scott signed into law statewide

expansion of Florida Medicaid managed care (Florida Statutes, 2011). This policy change

involves the required enrollment of Medicaid recipients into managed care organizations.

Through this financing system, managed care organizations are paid a set per member per

month fee to coordinate the healthcare of their enrollees. While the implementation of a

pilot program of Medicaid Reform has been successful in many respects (Landry, Lemak,

& Hall, 2011), all risk-based payment systems suffer from unfortunate realities that are

difficult or expensive to monitor by regulators (Eisenhardt, 1989). In the worst case,

potentially unprofitable Medicaid recipients could be subjected to discrimination by

managed care plans that may want to avoid enrolling them into their plan or to shirk

expensive care management and/or quality improvement responsibilities that could

improve their health (Van de Ven & Ellis, 2000). These prohibited behaviors may be

exacerbated because of the inability of managed care organizations to collect data on the

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long-term financial benefits of care management (i.e., prevention, treatment adherence)

due to high membership turn-over typically found in Medicaid managed care (Short,

Graefe, & Schoen, 2003).

In response to these Medicaid managed care vulnerabilities, the Agency for

Health Care Administration (AHCA), Florida’s Medicaid regulator, requires managed

care organizations to conduct disease management programs (including HIV/AIDS) and

report quality-related process measures (including ART utilization among enrollees

diagnosed with AIDS) (Landry et al., 2011; Agency for Health Care Administration,

2009). Currently, AHCA does not provide bonuses for meeting or exceeding the

requirements, rather, the results are published for potential enrollees to review. Due to

membership instability, regulations that offer weak financial incentives may not be

enough to induce managed care organizations to invest in care management activities that

will benefit the long-term health of members since the managed care organizations will

not directly benefit in the near-term.

This research determined the demographic, geographic, and clinical factors

associated with ART non-adherence (versus ART adherence). Additionally, this research

contributed to the evidence regarding the relationship of ART non-adherence to

healthcare expenditures as compared to those subjects not adherent to ART. The main

explanatory variable in this part of the research was ART non-adherence, and the

outcome variables was total healthcare expenditures in a 24 month period.

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Chapter Two: Review of the Literature

ART adherence

There is no recognized “gold standard” for measurement of adherence to ART

(Mills et al., 2006). While researchers acknowledge that measurement of ART adherence

relies heavily on the assumption that filling prescriptions is strongly correlated with the

patients actually taking the medicines (Reynolds, 2004), using pharmacy claims data has

been found to be valid proxy for medication consumption (Steiner & Prochazka, 1997).

Many studies measure ART adherence through pharmacy claims records (Grossberg &

Gross, 2007), and those that investigate a dose-response relationship show significant

relationship of ART adherence to both virologic failure (Smith, Rublein, Marcus, Brock,

& Chesney, 2003) and mortality (Nachega et al., 2006).

There is no consensus among researchers as to the best cut-off for ART adherence

as a dichotomous measure. In a review of North American and Sub-Saharan African ART

adherence studies from 1998 to 2006, 26 research teams defined adherence as 100%, 20

greater than 95%, six as greater than 90%, and six as greater than 80% (Mills et al.,

2006). In the Mills et al. (2006) meta-analysis, large heterogeneity in adherence to ART

(26% to 86%) existed across studies, accounting for different adherence measure

thresholds. A pooled proportion of North American patients’ adherence to ART was 55%

(95% CI, 0.49-0.62). Another study of 244 HIV-infected Medicaid-insured patients

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showed that 60% of patients were adherent with >80% of their antiretroviral therapy in

the past week, 43% were >90% adherent, and 29% were 100% adherent (Eldred, Wu,

Chaisson, & Moore, 1998). In the subsequent multivariable analysis by Eldred et al. of

the factors associated with ART adherence, the authors defined the values for the

dependent variable as > 80% equal to adherent. Regarding demarcation of low adherence,

Kitahata et. al (2004) created the categorical ART low adherence measure at below 70%

MPR. The study showed significant differences in viral rebound and higher CD4 cell

counts over 12–24 months, as compared to middle (70% to 90%) and high ART

adherence groups (>90%).

Complicating ART adherence measurement, recent data suggest that each

regimen class may have different adherence-resistance relationships (Bangsberg, Kroetz,

& Deeks, 2007). For example, a study by Maggiolo et al. (2005) found that when

comparing NNRTI versus PI-based ART regimens, the level of adherence required to

prevent of virologic failure was not equal. They found that at similar adherence rates,

between 76%–99%, PI-based have a higher virologic failure rate than NNRTI-based

regimens. Similarly, another study found that higher levels of adherence were required of

PI-based to antiretroviral drug resistance compared to NNRTI-based regimens

(Bangsberg, 2006). Together, these studies underscore the difficulty in drawing a “bright

line” of dichotomous ART adherence, though numerous studies have done so in the past.

When measuring ART adherence in categorical groups, as seen in Nachega et al.

(2010) and Gardner et al. (2008) research, ART adherence was created by dividing the

study sample into equal numbered quartiles. In these studies, quartiles were created with

the highest adherence groups defined as 100% adherent, and the lowest adherence groups

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measured at > 20%. Both studies analyzed the relationship of healthcare expenditures to

ART adherence by comparing the lowest quartile expenditures to the highest quartile

expenditures.

Key factors associated with ART adherence

Since the advent of antiretroviral medications in 1996, many researchers have

investigated the problem of adherence to ART, most focused on identifying associated

factors. While many factors have been identified by this research, few were reliably

reproduced across studies (Reynolds, 2004). In fact, a review summarizing the results of

20 studies scrutinizing ART adherence factors, only a handful of determinants were

consistently and statistically related to non-adherence: treatment related symptoms and

side-effects, stress, lack of social or family support, inconvenience and complexity of the

treatment, and low patient self-efficacy (Ammassari et al., 2002). Other possible key

determinants of decreased ART adherence include CD4 count, no outpatient visits

(Gordillo, del Amo, Soriano, & González-Lahoz, 1999; Kleeberger et al., 2001), non-

white race (Kong, Nahata, Lacombe, Seiber, & Balkrishnan, 2012; Lillie-Blanton et al.,

2010; Zhang, Senteio, Felizzola, & Rust, 2013), younger age (Becker, Dezii, Burtcel,

Kawabata, & Hodder, 2002), male sex, and geography (urban versus rural) (Chesney,

2000). Also, the specific ART regimen, such as protease inhibitor-boosted versus

NNRTI, (Altice, Mostashari, & Friedland, 2001; Trotta et al., 2002) and number of

concurrent medications in regimen, showed an association to adherence, controlling for

other factors (Bangsberg, Ragland, Monk, & Deeks, 2010; Kleeberger et al., 2001; Lazo

et al., 2007; Maggiolo et al., 2005).

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Outpatient care may be related to medication adherence among HIV/AIDS

patients. Bakken et al. (2000) conceptualized engagement with a healthcare provider

along multiple dimensions, including perceived access to healthcare provider. Also,

according to the Primary Care Guidelines for the Management of Persons Infected with

Human Immunodeficiency Virus, cell counts and low viral loads should be monitored

every three to four months to monitor for drug toxicity and to assess response to ART

(Aberg et al., 2009). Finally, Giordano et al. (2007) found that patients had visits to an

HIV outpatient clinic at least once a quarter over four quarters had lower adjusted hazard

ratio of mortality, as compared to those patients with three or less quarterly visits in the

same period.

Sustained case management interventions, such as education and counseling, have

been found to improve ART adherence for PLWHA (Katz et al., 2001; Pradier et al.,

2003). For this research, the Project AIDS Waiver (discussed below) provided to some

qualified Florida Medicaid AIDS patients has produced some evidence suggesting

expenditure-reducing impact of case management services (Anderson & Mitchell, 1997).

Also, alcohol abuse (AA), substance abuse (SA), depression, anxiety and

somatoform diagnoses, antidepressant treatment adherence, and outpatient mental health

treatment are important associated factors with ART adherence. Studies by Mellins et al.

(2009), Hendershot et al. (2009) and Hicks et al. (2007) found a significant negative

association between SA and/or AA and ART adherence. In addition, depression, anxiety

and somatoform diagnoses are significantly negatively related to ART adherence

(Horberg et al., 2008; Kleeberger et al., 2001; Tegger et al., 2008). Recent research by

Horberg et al. (2008), Walkup et al. (2007), Dalessanro et al. (2007) and Yun et al.

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(2005) found that adherence to antidepressants had a significantly positive relationship to

ART adherence. Safren et al. (2009) found that outpatient mental health treatment

increased the likelihood of ART utilization.

On the other hand, severe mental illness (SMI), including schizophrenia and

bipolar disorder, may have a positive relationship to ART adherence. Himelhoch et al.

(2009) found that ART discontinuance was significantly lower for patients with SMI

diagnoses, versus those without a SMI diagnosis. These results are consistent with

evidence that providers are more likely to initiate ART for patients diagnosed with

schizophrenia, if they are also receiving psychiatric care (Himelhoch, Powe, Breakey, &

Gebo, 2007). It is believed that the positive relationship of SMI and ART adherence may

be the result of improved care coordination provided to PLWHA in HIV specialty clinics

(Ohl, Landon, Cleary, & LeMaster, 2008).

While most research is focused on the association of mental illness comorbidities

with HIV care, Crawford et al. (2013) found that patients with non-HIV co-occurring

chronic diagnoses, including cancer, cardiovascular, cerebrovascular, respiratory,

diabetes, or depression had significantly improved retention in care, as compared to those

patients without any of those chronic disease diagnoses. Also, Giordano et al. (2007)

found that PLWHA with comorbid condition had improved retention in HIV care, as

compared to those without comorbidities. When reporting on retention to HIV care, the

authors recognized that the relationship between retention in care to survival is mediated

by adherence to ART. Finally, Webster (2010) in a study of HIV-infected veterans found

that those subjects with cardiovascular disease had higher ART adherence than those

without cardiovascular disease.

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Finally, there are multiple options for antiretroviral therapy regimens, and the

treatment choice is dependent upon an individual patient’s clinical stage, other

comorbidities and pharmaceuticals, and tolerance for various antiretroviral medication

side-effects (Volberding, 2008). Research has found that there are varying ART

adherence rates for different regimens, depending on specific pharmaceutical side-effects,

number of pills, and complexity (Altice et al., 2001; Kleeberger et al., 2001; Trotta et al.,

2002). For example, Altice et al. (2001) found that a boosted protease inhibitor ART

regimen was associated with a threefold higher risk for non-adherence, as compared to

two NRTI combination therapies.

ART adherence association with total healthcare expenditures

Bozzette et al. (2001) and Nachega (2010) found that ART adherence was

independently related to a reduction in expenditures. However, the researchers arrived at

this conclusion using different study samples, methods and statistical techniques.

Bozzette et al. (2001) assessed the relationship of ART use to total expenditures in a 28-

month survey that began in January 1996, just as the first protease inhibitors were

prescribed. Using a U.S. probability sample from 28 cities plus 25 clusters of rural

counties, the authors interviewed 2,864 HIV-infected adults. Self-reported information

about use of protease inhibitors or non-nucleoside reverse-transcriptase inhibitors at four

interviews - June 1996, March 1997, November 1997, and October 1998 - acted as

independent variables. Pharmaceutical costs were estimated using prices from a national

retail pharmacy, a federal distributor of drugs, and a hospital buying consortium.

Antiretroviral medication costs represented 54% of total average costs among the study

subjects in July 1998. Medical service expenditures were estimated from payments in

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administrative records or cost-to-charge ratios from a third of hospitals and a quarter of

outpatient service locations. Total monthly costs per patient for each of the four

interviews, adjusted for 1996 U.S. dollars, acted as the dependent variables.

Using this panel data, Bozzette et al. (2001) developed regression models to

predict total expenditures, adjusting for the dates of each set of interviews, changes in

clinical status and deaths, and such covariates as insurance coverage (including

Medicaid), race, clinical stage, age, sex, education, region, risk group (e.g., intravenous

drug use), and size of HIV practice of the treating physician. The authors found that total

expenditures decreased from 1996 to 1998 for the sample of HIV patients; the differences

between the 1997 and 1998 total expenditure estimates, however, were not significant.

Predictors, such as public insurance coverage, PLWHA seeing physicians that care for

more than 500 HIV patients, and PLWHA taking protease inhibitors or non-nucleoside

reverse-transcriptase inhibitors, were related to a decrease in expected per patient

monthly costs. The authors concluded that ART may reduce total expenditures by

reducing hospital services in the near-term.

Nachega (2010) assessed the effect of ART adherence on mean expenditures on

6,833 HIV-infected South African adults who started ART during the study period.

Adherence to ART was measured as the number of months with ART claims divided by

the number of complete months from ART initiation to death, withdrawal, or study end,

multiplied by 100 (called medication possession ratio). Adherence to ART was the

categorized into quartiles of the sample, including 1st (20%), 2nd (60%), 3rd (85%), and

4th (100%) quartiles. ART costs accounted for only 13% of total costs - a relatively low

percentage compared to other studies discussed in this research. The average monthly

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healthcare cost per patient per month, the dependent variable, was calculated as the total

costs for the five-year follow-up period and divided by number of complete months from

ART initiation to death, withdrawal from program, or study end.

Using a logit function to account for the probability of nonzero costs, Nachega et

al. (2010) then used a generalized linear model to predict the mean monthly per patient

expenditures. Data analysis corrected for the heteroscedasticity of multiple measures per

patient using Huber-White standard errors. The lowest quartile (20%) adherence variable

was the reference quartile for the three other quartiles (100%, 85%, and 60%) in the

analysis. Moving from lowest ART adherence quartile to higher adherence quartiles was

associated with lower mean monthly healthcare costs suggesting that ART adherence on

total expenditures exhibited a dose-response relationship.

On the other hand, both of the Gardner et al. (2008) and Acurcio et al. (2006)

found that improved adherence to ART was associated with an increase in total mean

medical expenditures. Gardner et al. (2008) conducted a cross-sectional analysis using

annualized cost data from 1997 and 2003 from an inner-city Denver hospital and

associated HIV clinics. The adherence measure was calculated as the average of ART

doses filled, divided by doses prescribed for the first 180 days after ART initiation. In

addition to the continuous ART adherence variables, quartiles were created among the

325 subjects - 1st (100%), 2nd (96.2% - 98.4%), 3rd (82.0% - 91.3%), and 4th (20.2% -

65.6%). The mean annualized healthcare costs were also divided into quartiles. The costs

calculated by using billed charges for services converted using Denver Health cost-to-

charge ratios adjusted for inflation to year 2005. The ART expenditure variable was

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calculated using average wholesale pricing (AWP) for antiretroviral drug costs,

representing 61% of the total average estimated costs.

Gardner et al. (2008) conducted two statistical analyses. First, a multivariate

logistic regression was fit using the highest expenditures quartile (versus other quartiles)

acting as the dependent variable, ART adherence (percentage) as the continuous

independent variable, while controlling for CD4+ cell counts, HIV-RNA levels,

opportunistic illnesses and mortality. The regression results showed that for every 10%

increase in ART adherence, the odds of a subject’s costs being in the highest quartile

decreased by 20%. Second, the next analyses conducted were multiple ANOVAs

comparing log-transformed annualized total medical costs across four adherence

quartiles. For these comparisons, total medical costs were significantly lower for those

with less than 65.6% adherence to ART (lowest quartile), as compared with the other

adherence quartiles.

Gardner et al. (2008) cautioned not to conclude that ART adherence is expensive,

despite the positive relationship of ART adherence and total healthcare expenditures.

Rather, they suggest that the positive relationship may be due to manufacturer pricing of

the antiretroviral drugs in the United States. However, when they ran the same analysis at

340B pricing levels - the federal HIV drugs purchasing program that reduced drug costs

by 38% in this study - the positive relationship of ART adherence to increased costs

remained. It was only at the generic drug pricing levels (3% of total healthcare costs) that

the adherence to ART was related to cost savings. While generic formulations of

antiretrovirals are available in many parts of the world, commercial patents prevent

marketing most generic antiretroviral drugs in the United States (FDA, 2011).

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Acurcio et al. (2006) also found that ART adherence significantly increased total

healthcare expenditures. This cross-sectional study, conducted with 306 previously

antiretroviral medication-naïve HIV-infected adults in Brazil, analyzed 9 months of

claims data from the national Sistema Único de Saúde. The adherence to ART was

measured through interviews asking the patient to self-report adherence in the previous 3

days. Patients reporting equal to or greater than 95% of the prescribed doses for 3 days

prior to the first follow-up visit were considered adherent. Total costs were measured

through Brazilian national health system fee schedule for the year 2002. Inpatient

expenditures were calculated as average cost of a hospital stay for the admitting

diagnosis. Antiretroviral medications represented 94.6% of total average cost among the

adherent patients and 90.0% among the non-adherent patients – the highest proportion of

antiretroviral pharmaceutical costs among the four studies discussed in this research.

Acurcio et al. (2006) conducted a multiple linear regression model to estimate the

contribution that ART adherence and use of protease inhibitors (independent variables)

had to total healthcare costs (dependent variable), controlling for other covariates, such as

age, sex, race, marital status, education, individual and family income, private health

insurance, initial clinical staging, initial CD4+ level. The researchers removed

statistically insignificant variables (p > 0.05) from the final multiple regression analysis.

Acurcio et al. (2006) also conducted a binary logit regression that examined the

relationship of ART adherence to cost effectiveness. In their multiple regression analysis,

the researcher found that adherence to ART was significantly associated with increased

total healthcare costs.

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Antiretroviral therapy background

Beginning with the introduction of antiretroviral medication in 1987, remarkable

advances have been made in the treatment of HIV (Dieffenbach & Fauci, 2011). In

particular, the simplification of regimens for ART-naïve patients (those taking

antiretroviral medications for the first time) have improved adherence by removing

barriers such as frequency of dosing, food requirements, and other adverse effects

(Bangsberg et al., 2010; Maggiolo et al., 2005; Nachega, Mugavero, Zeier, Vitória, &

Gallant, 2011). The goal of ART is to suppress HIV replication, requiring simultaneous

use of multiple drugs (Volberding, 2008). Typically, two nucleoside reverse transcriptase

inhibitors (NRTI) are combined with either a) non-nucleoside reverse transcriptase

inhibitors (NNRTI) or b) a boosted protease inhibitor (PI). Other less common

antiretroviral medication classes include integrase strand transfer inhibitors (INSTI),

chemokine receptor (e.g., CCR5), and fusion inhibitors (e.g., enfuvirtide) (Panel on

Antiretroviral Guidelines for Adults and Adolescents, 2011). Also, a recent and

preliminary study described the combination of INSTI and NNRTI drug classes,

specifically raltegravir (INSTI) and etravirine (NNRTI), and found the combination as

effective at controlling PLWHA viral load (Calin et al., 2012). In addition, although not

yet recommended by the Panel on Antiretroviral Guidelines for Adults and Adolescents

(2011), an alternate ART regimen combines PI and NNRTI in order to exclude NTRIs for

select patients that may be resistant (Joly, Descamps, & Yeni, 2002; Tebas et al., 2007).

This therapy choice is called “nucleoside-sparing” (Tebas et al., 2007). The choice of

ART regimen combinations is dependent upon an individual patient’s clinical stage, other

comorbidities and drugs, and tolerance for various antiretroviral medication side-effects

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(Volberding, 2008). ART regimen decisions are relatively simple in early stages of HIV

progression (so-called first-line regimens), but become more complex due to

antiretroviral drug resistance and/or drug interactions with other disease treatments

(Volberding, 2008).

Successful multiple-drug combinations of ART began in the mid-1990s. Since

that time numerous swings in the expert opinion regarding the appropriate time begin

treatment ensued (Wilkin & Gulick, 2008). According to the Panel on Antiretroviral

Guidelines for Adults and Adolescents (2011), ART should be initiated in all patients

with a history of an AIDS-defining illness, with a CD4 count less than 350 cells/mm3,

pregnancy, HIV- associated nephropathy, or hepatitis B virus (HBV) co-infection.

Despite this, current opinion is split on whether to start ART earlier than at CD4 counts

<350 cells/mm3. According to the expert opinion of the Working Group of the Office of

AIDS Research Advisory Council Patients, a panel of the U.S. Department of Health and

Human Services (2011), there are four cited reasons that opinions have shifted to earlier

initiation of ART.

First, at least one study demonstrated survival benefit with initiation of ART at

CD4 count >500 cells/mm3. Also, if left untreated, HIV infection may be associated with

comorbidities, such as cardiovascular disease, kidney disease, liver disease, and

malignancy. Next, new ART regimens are more effective and convenient, but provide

less side-effects than previous medications. Finally, evidence suggests that ART may

reduce HIV transmission. Despite these justifications, the remaining 50% of the Panel

(2011) thought that additional evidence is needed to recommend ART initiation >500

cells/mm3 pointing to the risks of side-effects associated with antiretroviral drugs, ART

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non-adherence for asymptomatic patients, and potential development of antiretroviral

drug resistance.

In July 2006 the FDA approved AtriplaTM, a combination drug with three active

antiretroviral medications, has been available as a single-tablet regimen (U.S. Food and

Drug Administration, 2009). AtriplaTM includes a non-nucleoside reverse transcriptase

inhibitor (NNRTI) and two nucleoside reverse transcriptase inhibitors (NRTI) (Julg &

Bogner, 2008). AtriplaTM is recommended as an option for simplifying first line regimen

(U.S. Food and Drug Administration, 2009).

Generic formulations of antiretroviral drugs are available in the marketplace.

However, due to legal market protections, some of the generics that meet safety, efficacy,

and manufacturing quality standards set by the FDA (“tentative approval”) cannot be sold

in the United States (FDA, 2011). Table 2.1 below lists the generic antiretroviral drugs

approved by the FDA that are marketed in the United States and whether the generic is

offered to Florida Medicaid-insured PLWHA through the AHCA Preferred Drug List

(PDL).

TABLE 2.1: FDA approved generic antiretroviral drugs

Drug Dose(s) FDA

Approval AHCA PDL

3/6/09 AHCA PDL

7/25/11 Didanosine 10 mg 3/8/2007 No Yes Didanosine 125mg 9/24/2008 Yes Yes Didanosine 200mg/250mg/400mg 12/3/2004 Yes Yes Stavudine 15mg/20mg/30mg/40mg 12/29/2008 Yes Yes Stavudine 1mg/mL 12/29/2008 No Yes Zidovudine 50 mg/5mL 9/19/2005 Yes Yes Zidovudine 60 mg 7/23/2009 No No Zidovudine 100 mg 3/27/2006 Yes Yes Zidovudine 300 mg 9/19/2005 Yes Yes

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Healthcare expenditures

Total healthcare expenditures for Florida Medicaid among PLWHA were a focus

of this research. Drivers of total healthcare expenditures for PLWA include comorbidities

(Fakhraei, Kaelin, & Consiver, 2001) and HIV or AIDS disease clinical classification

(Fleishman, Hsia, & Hellinger, 1994). In addition, Anderson and Mitchell (1997)

concluded that Florida Medicaid Project AIDS Care (PAC) case management reduced

total per-capita expenditures, principally because of reduced inpatient costs despite

substantial increases in pharmaceutical costs. Although PAC waiver enrollees had higher

drug spending, they represent only a fraction of the higher inpatient costs incurred by

non-waiver enrollees. In a previous study, Anderson and Mitchell (1997) found that after

controlling for selection bias and demographic factors, a 22% savings was associated

with enrollment in the Florida PAC case management program. Finally, Bozzette et al.

(2001) found that care provided by an HIV/AIDS specialist was significantly related to

decreased expenditures for PLWHA - perhaps due to efficiencies gained through

experience caring for PLWHA.

The relationship of ART adherence and total healthcare expenditure-related

variables is a main interest of this research. Across all HIV-severity levels, a substantial

proportion of healthcare costs for HIV/AIDS in the United States can be attributed to

antiretroviral medication (Bozzette et al., 2001; Gardner et al., 2008; Gebo et al., 2010).

As discussed above, contradictory evidence has been published on the relationship of

ART adherence on total healthcare expenditures. Bozette et al. (2001) and Nachega

(2010) found that ART adherence was related to decreased expenditures, while Gardner

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et al. (2008) and Acurcio et al. (2006) found ART adherence was related to increased

costs. Another study (Fleishman, Gebo, et al., 2005) found that expenditures for inpatient

and outpatient services for patients on ART were not significantly lower than patients not

on ART.

Inpatient utilization

Inpatient utilization comprises a large proportion of total medical costs in the

United States. Among a nationally representative annual survey of approximately 15,000

households (Medical Expenditure Panel Survey) in 2009 found that overall expenditures

were primarily for inpatient treatment (31.3%), office-based visits (23.5%), and

prescription medications (20.7%). For chronic conditions, the proportion of

pharmaceutical costs relative to total medical expenditures (34.8%) outpaced inpatient

treatment (29.9%) (Conway, Goodrich, Machlin, Sasse, & Cohen, 2011).

Among New York Medicaid recipients diagnosed with HIV, Laufer et al. (2011)

found that the 2007 inpatient care expenditures made up 50.2% of total costs for the high-

cost group (those over $100,000 annual total costs; median of $157,209/year), and 26.1%

of total expenditures for medium-cost recipients (median of $24,800/year). According to

Krentz and Gill (2010), for AIDS-diagnosed patients, 21% of the total healthcare costs

were attributable to inpatient services in the first year. After the first year, mean annual

costs decreased by 25% per year – mostly due to reduced inpatient costs attributed to

active treatment. In subsequent years, inpatient costs account for less than 10%.

Upon the introduction of ART in late 1995, inpatient admissions and length of

stay (Mouton et al., 1997; Torres & Barr, 1997) and inpatient expenditures (Keiser,

Nassar, Kvanli, et al., 2001b) decreased for PLWHA. Bozzette et al. (2001) and Nachega

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et al. (2010) found that ART was accompanied by a significant reduction in inpatient

utilization. Similarly, Fleishman et al. (2005) found that ART use was negatively related

to inpatient admissions. This reduction in hospital use is consistent with research

pertaining to increased adherence to medications for other chronic diseases, such as

diabetes, hypertension, hypercholesterolemia, and congestive heart failure (Sokol et al.,

2005). Interestingly, Bozzette et al. (2001) found that after a decline after 18 months of

ART hospital costs had increased to baseline levels. The researchers speculated that the

increase may have been due to ART resistance. Still, consistent with the established

theme, Bozzette et al. (2001) found that overall healthcare costs decreased in the two

years after starting ART.

The Anderson and Aday (1978) behavioral model on the determinants of

healthcare utilization provides a framework for understanding variables associated with

inpatient utilization. The behavioral model characterizes factors as predisposing (age,

sex, race), enabling (travel circumstances) and need-based (perceived disability,

diagnosis). Disease comorbidities are commonly included in healthcare utilization models

as need-based drivers of inpatient care. For example, according to one study of the

general HIV/AIDS population in the United States, HIV and hepatitis C virus (HCV) co-

infection prevalence was found to be 16.1% (Sherman, Rouster, Chung, & Rajicic, 2002).

Since Gebo et al. (2003) found that patients co-infected with HIV-HCV were more likely

to experience costly hospital admissions, HCV is a key comorbidity to be considered in

this research. Also, an AIDS clinical classification (versus non-AIDS HIV), was found to

be a predictor of hospitalization (Fleishman, Hsia, & Hellinger, 1994).

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Comorbidities among PLWHA

Depression, anxiety and somatoform disorder diagnoses are highly prevalent

among PLWA. Research conducted in the United States in 2001 showed that

approximately 36% of patients with HIV had major depression and that 15.8% had

generalized anxiety disorder, and 10.5% suffered from panic attacks (Bing et al., 2001).

A subsequent study found that 13% had a triple diagnosis: HIV, mood and/or anxiety

disorders, and drug dependence symptoms and/or heavy drinking (Galvan, Burnam, &

Bing, 2003).

Considerable evidence demonstrates that depression, anxiety and somatoform

diagnoses complicate the adherence to ART (Pence, 2009; Leserman, 2008; Walkup et

al., 2007). Separate studies that examine depression (Horberg et al., 2008) and anxiety

(Roux et al., 2009) diagnoses found significant negative association of those diagnoses to

ART adherence, controlling for covariates.

However, the relationship between psychiatric illnesses and antiretroviral

treatment is complex (Ownby, 2010). It is possible that antiretroviral medications that

impact the central nervous system may cause psychiatric side effects, such as depression

and anxiety (Treisman & Kaplin, 2002). The non-nucleoside reverse-transcriptase

inhibitor, efavirenz, has been linked to neuropsychiatric disorders, such as depression,

mood changes, irritability, nervousness, and anxiety (Fumaz et al., 2005; Rihs et al.,

2006). Case reports compiled by Cespedes and Aberg (2006) indicate that other ART

component drugs (i.e., Zidovudine, Abacavir, Nevirapine) may be related to

neuropsychiatric reactions, including depression, agitation, and anxiety.

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On the other hand, the treatment of depression, anxiety and somatoform disorder

diagnoses appears to be positively associated with ART adherence. A randomized

controlled study by Safren et al. (2009) showed that PLWHA that received cognitive

behavioral therapy in an outpatient setting had an increased likelihood of ART utilization.

Also, a 2007 study found for those HIV-positive individuals with an antidepressant

prescription, the odds of current-month antiretroviral adherence were increased by almost

30% for those with antidepressant use in the prior month, after controlling for other

factors (Walkup et al., 2007). Research by Horberg et al. (2008) and Yun et al. (2005)

confirmed that antidepressant utilization improved adherence to ART.

The presence of a co-occurring mental illness diagnoses has been associated with

significantly greater healthcare expenditures and utilization for PLWHA (Henk,

Katzelnick, Kobak, Greist, & Jefferson, 1996; Katon, Lin, Russo, & Unutzer, 2003;

Koopmans, Donker, & Rutten, 2005; Stein, Cox, Afifi, Belik, & Sareen, 2006; Wittchen,

2002). Similar studies regarding other chronic diagnoses show increased costs associated

with mental illness (Egede, Zheng, & Simpson, 2002; Richardson et al., 2006). It is

thought that these increased costs may not be directly related to mental illness treatment,

but rather a consequence of increased overall medical service utilization (Simon, 2003).

Hansen et al. (2002) found that patients with depression or anxiety diagnoses had

more than three times increased odds for being high-users of non-psychiatric inpatient

care, as compared with patients without psychiatric diagnoses, controlling for disease

severity. (Somatoform disorders had more than six times increased odds). Also, there is

evidence that anxiety or depression are significantly associated with increased inpatient

utilization (Grabe, Baumeister, John, Freyberger, & Völzke, 2009).

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Several recent studies have examined the association of non-HIV chronic diseases

to HIV care and showed that those with one or more non-HIV chronic disease diagnosis

was associated with improved measures of care, including ART adherence and retention

in care (Crawford et al., 2013; Giordano et al., 2007; Webster, 2010). Prevalent chronic

diseases include hypertension COPD, hepatitis C, diabetes, asthma, chronic ischemic

heart disease, cardiac insufficiency and myocardial infarction, osteoarthritis, chronic

kidney disease, shingles and peripheral neuropathy (Gingo et al., 2012; Kim et al., 2012;

Vance, Mugavero, Willig, Raper, & Saag, 2011).

Hepatitis B (HBV) and C (HCV) co-infection is high among individuals

diagnosed with HIV or AIDS. Hepatitis and HIV infection share pathways of

transmission, such as sexual transmission and intravenous drug use (Qurishi et al., 2003).

According to one study of the general HIV/AIDS population in the United States, HIV-

HCV co-infection prevalence was found to be 16.1%, and among high risk subjects

(defined by drug use or hemophilia and <100 cells/µl), 100% were infected with HCV

(Sherman et al., 2002). Also, a study by Braitstein et al. (2006) found that PLWHA co-

infected with HCV were significantly less likely to be adherent to ART (42%) than those

without HCV (72%). Sub-optimal adherence may be due to hepatic toxicity associated

with ART (Melvin, Lee, Belsey, Arnold, & Murphy, 2000).

Florida Medicaid and HIV/AIDS

According to the latest estimates, prevalence of HIV in the United States is

approximately 1.1 million individuals (CDC, 2010). As of 2010, Florida had reported

117,612 cumulative AIDS cases, and is the third highest in cumulative reported AIDS

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cases the U.S. (CDC, 2010). According to Florida state records, an estimated 6,000 new

HIV cases are diagnosed each year (Florida Department of Health, 2009).

According to Kaiser Family Foundation (2009), Medicaid covers more people

diagnosed with HIV than all other insurance type, and that PLWHA are three to four

times more likely to be covered by Medicaid than the U.S. population overall. An HIV-

positive status does not necessarily mean that individuals qualify for Medicaid, so they

must become disabled from the disease to obtain Medicaid coverage (Kaiser Family

Foundation, 2009). In fact, most individuals diagnosed with HIV who qualify for

Medicaid are low-income and disabled, and qualify for Medicare Supplemental Security

Income (SSI) benefits (Kaiser Family Foundation, 2004). Most adults diagnosed with

HIV/AIDS are eligible for Medicaid because they are both low-income (below 75% of

the federal poverty level) and permanently disabled, as defined by the U.S. Social

Security Administration (“Social Security for People Living with HIV/AIDS,” 2005).

Many that are newly diagnosed with HIV are already enrolled in Medicaid (Kaiser

Family Foundation, 2009). Individuals that qualify for Medicare, AIDS Drug Assistance

Programs (ADAP), or commercial insurance were not included as subjects in this

research.

Florida Medicaid is administered and financed by the Agency for Health Care

Administration (AHCA). The Florida Medicaid programs include traditional fee-for-

service (FFS), pre-paid mental health plans (PMHP), primary care case management

(MediPass). Within the FFS financing strategy, AHCA pays healthcare providers directly

for the services rendered to Medicaid recipients. AHCA contracts with pre-paid mental

health plans (PMHP) to coordinate mental health benefits. These PMHPs are paid

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capitation by AHCA to coordinate mental health services, but all other services are paid

by AHCA through the FFS claims system. AHCA also contracts with MCOs and similar

managed care organizations to coordinate care to Medicaid enrollees. As of June 2011,

these managed care organizations enrolled 46% of the total Medicaid recipients in Florida

(Agency for Health Care Administration, 2011). For most of Florida Medicaid recipients,

enrollment into managed care was optional. However, in 2006 AHCA implemented the

Florida Medicaid Reform pilot in two AHCA geographic regions, Areas 4 and 10, in

which enrollment into managed care was mandatory. Finally, within the MediPass

program, primary care providers were paid a small monthly case management capitation

fee ($3.00), but were reimbursed for services delivered via Medicaid FFS.

In addition to the financing strategies described above, AHCA also conducts

various waivers, including a disease management program for Medicaid recipients

diagnosed with AIDS. The Florida Project AIDS Care waiver (PAC) can be categorized

as a FFS financing strategy with supplemental disease management funded by AHCA for

6,000 patients diagnosed with AIDS (Anderson & Mitchell, 2000).

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Chapter Three: Methods

Among ART-naïve PLWHA enrolled in Florida Medicaid (excluding Medicaid

managed care enrollees), the objectives of this research were a) to assess the determinants

of non-adherence to ART and b) to analyze the association of ART non-adherence to

healthcare expenditures.

Data

The data for this research included Florida Medicaid fee-for-service (FFS) claims

and Prepaid Mental Health Plans (PMHP) encounters for five fiscal years (July 2006

through June 2011). Managed care encounter data were excluded. Claims data included

diagnosis codes (ICD-9), procedure codes (CPT), condition codes (V codes), and

pharmaceutical codes (NDC). In the Medicaid FFS administrative claims set, inpatient

claims data included up to five diagnoses, and outpatient claims included only one

diagnosis. The enrollment data included demographics (age, sex, race, and eligibility

status), third party coverage periods, Medicaid coverage periods, and Medicaid

disenrollment reason (including death).

Sampling methods and inclusion criteria

Identification of HIV-positive individuals for this research was made through an

algorithm based on specific diagnosis, procedure, and pharmaceutical codes - the same

algorithm used by Florida Medicaid in the Reform Pilot (Hidalgo, 2009). The algorithm

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examined claims data for any combination of the procedure codes, NDC drug codes or

primary diagnosis codes. If there were two or more matches with the relevant procedure,

diagnosis or drug codes (NDCs) in different months, then the member was classified as

having HIV. If any of the secondary diagnosis codes, such as opportunistic infections

(e.g. candidiasis of lung) or other AIDS-related conditions (e.g. Kaposi's Sarcoma) were

present, then the patient was classified as having an AIDS-diagnosis. Also, subjects

enrolled into the Project AIDS Care waiver, according to the enrollment data were

considered as diagnosed with AIDS.

This research included non-pregnant adults ages 18 through 64 only. Claims for

patients identified as having been diagnosed with HIV or AIDS were reviewed for at least

one treatment with antiretroviral therapy (defined below). Subjects were excluded if

patient was not antiretroviral treatment-naïve for 12 months prior to the 24 month

measurement period. Treatment naïve was defined as any patient having not initiated

ART for 12 months prior to the measurement period.

Recipients with less than six months of FFS activity (i.e., managed care

financing) were excluded, and subjects with lapses greater than 3 months per year in the

measurement period were excluded. Medicaid managed care data was not available for

this research. Any recipient with Medicare coverage were excluded, as the healthcare

claims were paid though different financing mechanism.

Individuals with hemophilia or von Willebrand disease, a disease that sometimes

requires very expensive factor replacement therapy were excluded from Objective 2 of

this research. Florida Medicaid state policy requires individuals with these diagnoses to

enroll in a 1915(b) Medicaid waiver disease management program. Florida Medicaid

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purchases the factor replacement therapy medications from one of the two state

contracted vendors. This rule applies to individuals in fee-for-service and managed care

programs (Agency for Health Care Administration, 2012). Two subjects were in the ART

adherent group (1 HIV, 1 AIDS) and ten in the non-adherent group (1 HIV, and 9 AIDS).

The following table describes the research selection criteria variables measures in

more detail.

TABLE 3.1: Analysis variables Measure Measure Statement Level of

Measurement Reference

Antiretroviral medication therapy (ART_flag)

An instance of an antiretroviral ndc. (see Appendix A1).

Dichotomous, with values of 1 if ART prescription measure is met, and 0 if not.

Nachega et al. (2010); Castillo et al. (2004)

ART naïve (NAIVE)

No ART_flag prescription refills in reference year.

Dichotomous, with values of 1 if ART naïve, and 0 if not.

Bozzette et al. (2001)

Medication possession ratio (MPR)

Filling prescriptions strongly correlated with medication consumption, and using pharmacy claims data has been found to be valid proxy for medication consumption

MPR was calculated as the number of days with ART prescriptions filled divided by the number of days in measurement period (24 months).

Reynolds (2004); Steiner & Prochazka (1997); Esposito et al. (2009)

HIV diagnosis Two or more matches with the HIV/AIDS procedure, diagnosis or drug codes (NDCs) in different months of the measurement year or 24 prior months. See Appendix Table A1.

Dichotomous, with values of 1 if the patient is diagnosed with HIV, and 0 if not.

Hidalgo (2009)

AIDS diagnosis An HIV diagnosis AND any secondary diagnosis codes in the measurement year or 24 prior months. (See Appendix Table A3.) A recipient enrolled in the AIDS PAC Waiver was defined as AIDS.

Dichotomous, with values of 1 if the patient is diagnosed with AIDS, and 0 if not.

Hidalgo (2009)

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Continued, TABLE 3.1: Analysis variables

HIV positive in reference year (HIV_REF)

HIV positive in reference year, as defined by presence of HIV and/or AIDS diagnosis variables (above).

Dichotomous, with values of 1 if the patient is HIV+ in reference year, and 0 if not HIV+.

Patient death (DEATH)

Flagged as death in enrollment file.

Dichotomous, with dummy values of 1 if the patient dies for each of the measurement years, and 0 if living.

Project AIDS Care waiver enrollment or case management services (PAC)

Case management intervention improves ART adherence

Dichotomous; Presence of PAC flag in AHCA enrollment files equal to 1; if not then equal to 0

Pradier et al. (2003); Katz et al. (2001)

Calculating healthcare expenditures

Healthcare expenditures were calculated as the amount that Medicaid paid to

providers and pharmacies for services (not charges), as indicated in the administrative

claims data for FFS and encounters for PMHPs. The analysis was conducted from the

perspective of Florida Medicaid, and therefore, did not include indirect costs.

Pharmaceutical pricing is defined below.

Missing data due to lapses in Medicaid coverage

Missing data is a challenge when using any public health database (Rubin, 1996).

The primary source of missing data when analyzing the Medicaid FFS claims and PMHP

encounter data for this research will be lapses in Medicaid coverage. Estimates from

Florida Medicaid administrative data reveal that about 7% of recipients with chronic

conditions (diabetes and depression) have at least a month in lapsed coverage (Hall,

Harman, & Zhang, 2008; Harman, Hall, & Zhang, 2007). Thus, considering the

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documented range of Medicaid enrollment churn, it is possible that lapses in Medicaid

coverage may approach 10% of the subjects for this research.

Therefore, subjects with enrollment lapses greater than three months in a year

were excluded, as this research assumed that the subject accessed needed care through

other sources. Patients with lapses in coverage equal to or less than three months within

the measurement period were coded with a “discontinuous coverage” dummy variable to

account for some of the unmeasured effects associated extended lapses in coverage. This

three month cut-off corresponds to “short” (one to two months) or “moderate” (three to

six months) lapses in Medicaid coverage, as described by Harman et al. (2007).

Furthermore, subjects that lose eligibility and do not later regain coverage were excluded,

as it was assumed that the subject obtained coverage and possibly antiretroviral drugs

through other sources. Those subjects with gaps in coverage of equal to or less than three

months were included in the sample. The denominator of the medication possession ratio

measure was counted the same as those without enrollment lapses, as those individuals

with short gaps can be reasonably assumed to be non-adherent to ART during the lapse

period.

Descriptive statistics

Descriptive statistics will be calculated for the study subjects. First, baseline

characteristics for the first ART adherence measurement year (2006) were reported for all

covariates, such as clinical classification (HIV/AIDS), race, sex, and selected

comorbidities (e.g., depression, anxiety, hepatitis C). In addition, patient characteristics at

ART initiation baseline for all variables by ART adherence - both > 90% versus < 90%

were reported. Comparisons between groups were made between groups using

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appropriate nonparametric tests (Hirsch, Rosenquist, Best, Miller, & Gilmer, 2009).

Standard tests, such as t tests and analysis of variance, will not be reported for

expenditures, as these tests were not appropriate for mean cost comparisons because of

likely non-normality (Nachega et al., 2010).

Inferential statistical analysis

The purposes of this research were to a) determine the effect of independent

factors on the probability of ART non-adherence and b) model the relationship between

those not adherent to ART and mean monthly total healthcare expenditures per patient for

ART-naïve subjects, controlling for covariates described below. Two different objectives

will be accomplished: 1) determine the factors that influence the probability a patient will

be non-adherent to ART, and 2) estimate the mean per patient total healthcare

expenditures for the measurement period.

Objective 1: Overview

Objective 1 assessed the independent determinants of non-adherence to ART

among Medicaid-insured treatment-naïve PLWHA using retrospective Florida claims

data.

Objective 1: Hypotheses

ART non-adherence will be significantly and negatively associated with counties

with high median income counties, urban county residence, female sex, age groups,

AIDS diagnosis, non-adherence to antidepressants, severe mental illness, meeting

minimum recommended average outpatient visits and ART regimen type; and

significantly and positively associated with race/ethnicity, substance abuse diagnosis

and/or alcohol abuse diagnosis, depression or anxiety diagnosis, disease progression from

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HIV to AIDS, Medicaid eligibility type, discontinuous Medicaid enrollment and co-

morbidity count levels.

Objective 1: Determinants of ART non-adherence

Adherence will be measured by a medication possession ratio of greater than or

equal to 90%; non-adherence will be less than 90%. A medication possession ratio

(MPR) is calculated as the number of days with ART prescriptions filled divided by the

measurement period. Dummy variables will be created for the ART non-adherence

outcome variable, coded as zero where the patient MPR for the 24 month ART

measurement period is greater than or equal to 90%, and coded to one otherwise.

In this objective, a one-equation multi-variable logistic regression model was used

to predict the effect of each factor’s effect on the odds of a given patient will be non-

adherent to ART. The logistic regression model uses the inverse standard normal

distribution to predict cumulative probability of a binary outcome (ART adherent versus

not ART adherent) specified as a function of a set of predictor variables (Molenberghs &

Verbeke, 2005). The results of the model presented the odds of an explanatory variable

on non-adherence to ART, when controlling for other independent variables.

The multivariable logistic regression model is as follows, where Pr is logit

probability of a subject being non-adherent to antiretroviral therapy (ART):

Logit Pr(NO_ART) = α + β1age_group1 + β2 age_group2 + β3County_low + β4County_urban + β5male_sex

+ β6black + β7Hispanic_RE + β8Other + β9SSI + β10ENG + β11DEP_ANX + β12AASA + β13PAC + β14SMI +

β15OPMH + β16MIRx + β17COM1 + β18AIDS + β19CHURN + β20NNRTI + β21Single_ARTClass + β22Rx_N2 +

β23Rx_N3 + β24Rx_N4 + β25DXP + ε (1)

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Where the parameters are: 1. Age_group1 = 18–34 year age group 2. Age_group2 = 35–49 year age group 3. County_Low = low median income county 4. County_Rural = rural county 5. Male_Sex = male sex 6. Black = black race, non-Hispanic 7. Hispanic_RE = Hispanic race and/or ethnicity 8. Other_Race = race not determined, Native American, Alaskan Native and Asian 9. SSI = Social Security Income Medicaid eligibility category 10. ENG = engagement with provider, (> 4 annual outpatient visits mean) 11. DEP_ANX = depression and/or anxiety diagnosis 12. AASA = alcohol abuse and/or substance abuse diagnosis 13. PAC = Project AIDS Care case management waiver or case management procedures 14. SMI = severe mental illness diagnosis 15. OPMH = Cognitive behavioral therapy outpatient mental health services 16. MIRx_yes = 2 or more antidepressant prescription claims 17. COM1= one or more non-HIV chronic disease diagnosis 18. AIDS = AIDS-diagnosis status 19. CHURN = Medicaid enrollment gap in 1 to 3 months within year 20. NNRTI = non-nucleoside reverse transcriptase inhibitor antiretroviral therapy 21. Single_ART_class = Antiretroviral medication regimen containing only one drug

class (e.g., INSTI, nuc-sparing and single ART) 22. Rx_N2 = two concurrent ARV medicines in first month of ART 23. Rx_N3 = three to five concurrent ARV medicines in first month of ART 24. Rx_N4 = six or more concurrent ARV medicines in first month of ART 25. DxP = Disease progression from HIV to AIDS

The following variables have been identified as related to ART adherence.

TABLE 3.2: Objective 1 model variables

Variable Theoretical

consideration Measurement Reference(s)

ART adherence (ART1)

Outcome variable. No consensus among researchers as to the best dichotomous cut-off for ART adherence.

Dichotomous; Medication possession ratio (MPR) greater than or equal to 90%, then coded 1 if the patient is adherent to ART, and 0 if not adherent.

Mills et al. (2006)

Sex (SEX) Male sex associated with non-adherence to ART

Dichotomous, with value of 0 if male and 1 if female

Chesney (2000)

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Continued, TABLE 3.2: Objective 1 model variables

Age group (AGE)

Younger age associated with non-adherence to ART

Categorical; Measured on July 1 of reference year. Age groups, 18–34 (reference), 35–49, and 50 years or older

Becker et al. (2002); Chesney (2000); Laine et al. (2000);

County Median Income (County_High, County_Low)

Evidence describes substantial variation in healthcare spending independently associated with geography

Categorical; defined by U.S. Census Bureau, 2005-2009 American Community Survey, divided into 2 groups by median household income; lower county group is reference; See Appendix Table A4

Race and Ethnicity (RACE)

Non-white race associated with non-adherence to ART

Categorical; white (reference), black, Hispanic race and/or ethnicity, Other (including Not Determined, Native American, and Asian); dummy variables for each category

Kleeberger (2001)

Supplemental Security Income-related disability (SSI)

Temporary Assistance for Needy Families (TANF) versus SSI

Dichotomous; presence of SSI eligibility status then equal to 1; if not then equal to 0

Depression, anxiety or somatoform diagnoses (DEP_ANX)

Depression, anxiety or somatoform diagnoses associated with decreased ART adherence

Dichotomous; presence of depression, anxiety or somatoform diagnoses then equal to 1; if not then equal to 0 (see App. Table A5)

Gordillo et al. (1999), Kleeberger (2001), Horberg et al. (2008)

Alcohol abuse and/or substance abuse (AASA)

Adherence to ART is negatively associated with alcohol abuse and substance abuse

Dichotomous; Presence of alcohol abuse and/or substance abuse diagnosis equal to 1; if not then equal to 0 (see App. Table A5)

Chesney (2000), Hinkin et al. (2007)

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Continued, TABLE 3.2: Objective 1 model variables

Severe mental illness (SMI)

Increases ART adherence, possibly through improved care coordination

Dichotomous; Presence of 1 or more severe mental illness diagnosis then equal to 1; if not then equal to 0 (see App. Table A5)

Bogart et al. (2006)

Outpatient mental health treatment (OPMH)

Mental health therapy increased the likelihood of ART utilization

Dichotomous; > 1 Cognitive Behavioral Health Therapy visits in measurement period equal to 1; if not then equal to 0

Safren et al. (2009)

Adherence to antidepressants (MIRx)

Adherence to antidepressant medications improves adherence to ART

Dichotomous; If 2 or more Rx and > 80% MPR equal to 1; if not then equal to 0

Horberg et al. (2008); Walkup et al. (2007); Yun et al. (2005)

Co-occurring chronic disease diagnosis

Co-occurring chronic diseases (e.g., diabetes, HCV, asthma, renal disease, heart disease) may increase likelihood of ART non-adherence

Dichotomous; Key chronic disease diagnoses, excluding HIV, AIDS, AA, SA, SMI, DAS; dummy coded as equal to 1 if present, zero as reference

Vance et al. (2011)

AIDS clinical classification (AIDS)

Conflicting evidence that AIDS (i.e., CDC disease stage) is associated with ART adherence

Dichotomous; Presence of AIDS-defining diagnosis or PAC waiver enrollment then equal to 1; if not then equal to 0

Gifford et al. (2000); Kleeberger et al. (2001)

Gap in enrollment (CHURN)

Post-lapse period is associated with increased expenditures

Medicaid coverage lapse greater than or equal to 1 and less than or equal to 3 months in a fiscal year equal to 1; if not then equal to 0.

Harman, Hall, & Zhang (2007); Hall, Harman, & Zhang (2008)

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Continued, TABLE 3.2: Objective 1 model variables Disease progression (DXP)

Non-adherence strongly positively related to disease progression from HIV to AIDS

Dichotomous; If HIV classification in first month of measurement year, and then presence of AIDS in a subsequent month, then equal to 1; if not equal to 0

Bangsberg et al. (2001)

Non-nucleoside reverse transcriptase inhibitor therapy (NNRTI)

ART regimens may have varying adherence due to different complexity and side-effects

2 nucleoside reverse transcriptase inhibitors (NRTIs) and one NNRTI in first month of measurement period with values of 1, and 0 if not.

Panel on Antiretroviral Guidelines (2011); Trotta et al. (2002)

Boosted protease therapy inhibitor (PI)

ART regimens may have varying adherence due to different complexity and side-effects

2 nucleoside reverse transcriptase inhibitors (NRTIs) and a ritonavir-boosted protease inhibitor (PI) in first month of measurement period with values of 1, and 0 if not.

Panel on Antiretroviral Guidelines (2011); Trotta et al. (2002)

Other ART regimen (Oth_ART)

ART regimens may have varying adherence due to different complexity and side-effects

Other ART regimen, including single ART regimens, Nuc-sparing (NNRTI and PI), FI, Chemokine receptor therapy, or INSTI in first month of measurement period with values of 1, and 0 if not.

Number of concurrent antiretroviral medications (Rx_N1, etc.)

Increased number of antiretroviral medications used concurrently may be related to lower adherence

Categorical; Counts of number of concurrent antiretroviral medications in first month; 1 medication as reference

Kleeberger et al. (2001); Maggiolo et al. (2005)

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See Appendix Table A4 for the U.S. Census Bureau, 2005-2009 American Community

Survey divided into half by median household income. The lower income county set is

the reference category in the model, including Calhoun, Dixie, Putnam, Holmes,

Highlands, Suwannee, Washington, Levy, Gadsden, Hamilton, Taylor, Jackson, Madison,

and DeSoto, Hendry, Citrus, Franklin, Gulf, Okeechobee, Hardee, Columbia, Glades,

Alachua, Liberty, Marion, Bradford, Union, Sumter, Gilchrist, Hernando, Leon, and

Miami-Dade. The upper income county set includes Escambia, Volusia, Pasco, Jefferson,

Polk, Charlotte, Lake, Pinellas, Walton, Bay, Baker, Osceola, Indian River, Lafayette, St.

Lucie, Flagler, Manatee, Sarasota, Brevard, Duval, Hillsborough, Orange, Lee, Broward,

Wakulla, Martin, Palm Beach, Okaloosa, Santa Rosa, Monroe, Nassau, Collier,

Seminole, Clay, and St. Johns. The demarcation point for median income for the lowest

high median income county is $43,326, Volusia County’s median income. Also in

Appendix Table A4 are the notations of the counties by population density (urban and

rural). Based on the 2010 U.S. Census data, there were 30 counties defined as rural in

Florida, as defined by a density of less than 100 persons per square mile.

Objective 1: Expectations

The dichotomous outcome variable was ART non-adherence (MPR< 90%) versus

ART adherence (MPR>90%). Certain factors were expected to significantly and

negatively associated with the probability that the patient would be non-adherent to ART,

including county median income (high versus low), rural county population density, male

sex, age groups, AIDS diagnosis, adherence to antidepressants, severe mental illness,

PAC Waiver enrollment or case management services, meeting minimum recommended

average outpatient visits, ART regimen type, and number of medications in the ART

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regimen. Positive significant independent variables included race/ethnicity, disease

progression from HIV to AIDS, substance abuse diagnosis, alcohol abuse diagnosis,

depression, anxiety or somatoform disorder diagnosis, Medicaid eligibility type,

Medicaid discontinuous coverage, and co-morbidity count levels.

Objective 2: Overview

The second objective is to assess the mean total healthcare expenditures in the

twenty-four month measurement period between those PLWHA subjects in the ART

adherence group (>90%) versus those in the non-adherence group (<90%), controlling for

demographic, geographic, insurance and clinical factors.

Objective 2: Hypothesis

The mean total healthcare expenditures (Q) for the multi-year period among those

PLWHA in the ART adherence group will be less than those in the low ART adherence

group. More formally,

H0: Q ART Adherence > Q ART non-Adherence

HA: Q ART Adherence � Q ART non-Adherence

Regression analysis estimated the expected per patient mean monthly total

healthcare expenditures in the measurement period. To account for the likely skewness of

the outcome variable, a generalized linear model (GLM) with a log link function and

gamma distribution will be utilized (Manning & Mullahy, 2001). GLM prevented the

need to transform the skewed expenditure data, and subsequently to retransform the

predicted expenditures back into dollar figures (Manning & Mullahy, 2001). GLM with

log-link and gamma distribution is the statistical method employed by Nachega et al.

(2010) in their study regarding the relationship of ART to healthcare expenditures.

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Total healthcare expenditures were calculated using Florida Medicaid FFS claims

and PMHP encounters in the 24 month period. Total healthcare expenditures per patient

per month were determined by adding expenditures for inpatient, outpatient, antiretroviral

medication, non-antiretroviral outpatient pharmacy, emergency department utilization,

outpatient mental health, inpatient mental health, and outpatient surgeries. Home health

care, hospice care, nursing home care, and radiological examinations were excluded.

Inpatient expenditures were defined as total per diem expenditures reflected on the

Medicaid claim. In Florida Medicaid, hospitals bill AHCA a pre-determined schedule of

rates per day. As a category, inpatient expenditures excluded behavioral health inpatient

expenditures.

For monthly pharmaceutical expenditure calculation, filled pharmacy claims from

all years used the expenditures listed on the Medicaid pharmaceutical claims minus the

29.1% rebate for drugs on the Florida Medicaid Preferred Drug List (PDL) and AWP

minus 16.4% rebate for non-PDL drugs (Florida Statute, 2008). It is important to note

that federally granted participants in the 340B program may purchase pharmaceuticals at

significant discounts, as compared to other organizations (Public Health Service Act,

1992). Pricing of pharmaceuticals is important to inferences of the ART adherence

impact on healthcare expenditures. In fact, Gardner et al. (2008) found that the positive

relationship of ART adherence to increased total expenditures did not exist when

pharmaceutical pricing was modeled at significantly discounted generic drug pricing,

reported as 3% of total healthcare expenditures.

Fakhraei et al. (2001) created a comorbidity-based payment methodology for

Maryland Medicaid enrollees with HIV/AIDS whereby the certain diagnoses that were

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associated with total healthcare costs. Each diagnosis was categorized according to the

relative effect on total expenditures. Despite the categorization of diseases, the diagnoses

in the Fakhraei co-morbidities-based payment methodology were individually additive to

costs (as opposed to hierarchical). That is, multiple diagnoses are counted within each

diagnostic classification or multiple diagnoses within different groups. Objective 2

follows the practice of counting the number of diagnoses. See Appendix Table A6 for the

list of all relevant diagnoses and the frequency among subjects in this research

Objective 2: Model variables

The following variables have been identified as related to ART adherence.

TABLE 3.3: Objective 2 model variables Variable Theoretical

consideration Measurement Reference(s)

Total healthcare expenditures (Q)

Ambiguity surrounds total cost savings related to ART adherence.

Continuous; Expenditures for inpatient, outpatient, antiretroviral medication, non-antiretroviral outpatient pharmacy, emergency department, outpatient mental health, inpatient mental health, laboratory studies, radiological examinations, and outpatient surgeries

Bozzette et al. (2001); Nachega (2010); Gardner et al. (2008); Acurcio et al. (2006)

ART adherence (ART1)

Outcome variable. No consensus among researchers as to the best dichotomous cut-off for ART adherence

Dichotomous; Medication possession ratio (MPR) greater than or equal to 90%, then coded 1 if the patient is adherent to ART, and 0 if not adherent.

Mills et al. (2006)

Age group (AGE)

Predisposing factor: Increased age a well-established factor associated with increased healthcare utilization

Categorical; with dummy variables for each age groups, 18–34 (reference), 35–49, and 50 years or older

Anderson and Newman (2005); Fleishman et al. (2005)

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Continued, TABLE 3.3: Objective 2 model variables

County Median Income (County_High, County_Low)

Evidence describes substantial variation in healthcare spending independently associated with geography

Categorical; defined by U.S. Census Bureau, 2005-2009 American Community Survey, divided into 2 groups by median household income; lower county group is reference; See Appendix Table A5

County Density (CountyR, County U)

Evidence describes substantial variation in healthcare spending independently associated with geography

Categorical; geographic compose of rural and urban, as defined by the U.S. Census Bureau; See Appendix Table A5

Sex (SEX_male)

Predisposing factor: Sex an established determinant associated with healthcare utilization

Dichotomous, with value of 0 if male and 1 if female

Anderson and Newman (2005); Fleishman et al. (2005)

Race/ethnicity (RACE)

Predisposing factor: Non-white race associated with increased healthcare utilization

Categorical; White (reference), black, Hispanic, other; dummy variables for each category

Anderson and Newman (2005); Fleishman et al. (2005)

Supplemental Security Income-related disability (SSI)

Temporary Assistance for Needy Families (TANF) versus SSI

Dichotomous; presence of SSI eligibility status then equal to 1; if not then equal to 0

Depression, anxiety or somatoform diagnoses (DEP_ANX)

Increased costs may be due to increased medical service utilization, not mental illness treatment

Dichotomous; presence of depression or anxiety then equal to 1; if not then equal to 0

Simon (2003)

Alcohol abuse (AA) and/ Substance abuse (SA)

Increased costs may be a consequence of increased overall medical service utilization, not mental illness treatment

Dichotomous; Presence of 1 alcohol and/or substance abuse diagnosis equal to 1; if not then equal to 0 (see Appendix Table A5)

Simon (2003)

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Continued, TABLE 3.3: Objective 2 model variables Severe Mental Illness (SMI)

Increased costs may be due to increased overall medical service utilization, not mental illness treatment

Dichotomous; Presence of 1 or more severe mental illness diagnosis (see Appendix Table A5)

Simon (2003)

Adherence to antidepressants (MIRx)

Conflicting evidence of adherence to antidepressant medications on healthcare utilization

> 2 months of antidepressant medication and > 80% adherence equal to 1; if not then equal to 0

Cantrell et. al (2006); Robinson et al. (2006)

Co-morbidities (COM0=0, COM1=1, COM2=2 or more)

Need-based driver of health services utilization

Categorical; Counts of key comorbidity diagnoses excluding HIV, AIDS, AA, SA, SMI; zero comorbidities as reference

see Appendix Table A6

AIDS clinical classification (AIDS)

Need-based driver of health services utilization

Presence of AIDS-defining diagnosis equal to 1; if not then equal to 0

Fleishman, Hsia, & Hellinger (1994)

Discontinuous Medicaid coverage (CHURN)

Post-lapse period is associated with increased expenditures

Dummy variable for each measurement year. Medicaid coverage lapse greater than 3 months in a fiscal year equal to 1; if not then equal to 0.

Harman, Hall, & Zhang (2007); Hall, Harman, & Zhang (2008)

Generic drug as a part of ART regimen (GEN)

Generic drug pricing can influence ART adherence impact on expected expenditures

Dichotomous; If a generic drug (see Table 1) is included in plurality of ART refills then coded as 1, and 0 if not.

Gardner et al. (2008)

Objective 2: Expectations

The relatively smaller mean monthly total healthcare expenditures for those

PLWHA in the ART adherence group versus the ART non-adherence group is based on

the expectation that, despite the significantly higher antiretroviral pharmacy expenditures,

the ART adherence group will have significantly less inpatient expenditures than the

ART non-adherence group.

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Chapter Four: Results

Final inclusion and exclusion criteria

The data for this research included Florida Medicaid fee-for-service (FFS) claims

and Prepaid Mental Health Plans (PMHP) encounters for five fiscal years (July 2006

through June 2011). Identification of HIV-positive individuals for this research was made

through the algorithm discussed in the methods section above (Hidalgo, 2009). No

subjects were pregnant nor had Medicare eligibility.

For those that had enrollment gaps of no more than 3 months at the end of a

measurement year, procedures were taken to evaluate whether the subject “churned” back

on to Medicaid later in the non-measurement period (n=66, 12.6%). These subjects were

noted in the model with a discontinuous enrollment (“churn”) variable. Those that had

gaps of less than four months, but did not return to Medicaid, were removed.

All subjects were ART medication-naïve (no antiretroviral therapy medication

claims) for at least 12 months prior to the first month of the subsequent 24 month

measurement period. Figure 5.1 illustrates how the 24 month measurement periods vary

for each subject. For example, of the 514 subjects, 14 individuals (2.7%) initiated ART

on July 1, 2006 and ended on June 30, 2008. In the next month, 15 subjects’ 24 month

measurement period started on August 1, 2006 and ended on July 31, 2008.

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Figure 4.1: Frequency of Subjects from Antiretroviral Initiation Month to End of Study in Twenty-Four Month Measurement Period (n=514)

First Month Last Month

Jul-06 Jun-08

Aug-06 Jul-08

Sep-06 Aug-08

Oct-06 Sep-08

Nov-06 Oct-08

Dec-06 Nov-08

Jan-07 Dec-08

Feb-07 Jan-09

Mar-07 Feb-09

Apr-07 Mar-09

May-07 Apr-09

Jun-07 May-09

Jul-07 Jun-09

Aug-07 Jul-09

Sep-07 Aug-09

Oct-07 Sep-09

Nov-07 Oct-09

Dec-07 Nov-09

Jan-08 Dec-09

Feb-08 Jan-10

Mar-08 Feb-10

Apr-08 Mar-10

May-08 Apr-10

Jun-08 May-10

Jul-08 Jun-10

Aug-08 Jul-10

Sep-08 Aug-10

Oct-08 Sep-10

Nov-08 Oct-10

Mar-08 Nov-10

Apr-08 Dec-10

May-08 Jan-11

May-08 Feb-11

Jun-08 Mar-11

Jul-08 Apr-11

Aug-08 May-11

Sep-08 Jun-11

12

9

13

16

18

8

5

5

21

16

9

16

6

8

16

12

11

16

12

7

13

10

10

11

12

|-------------------------TWENTY-FOUR MONTH PERIOD-------------------------|

|-------------------------TWENTY-FOUR MONTH PERIOD-------------------------|

14

15

15

13

10

8

12

5

14

13

12

12

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The ART adherence groups were analyzed for difference in means of the start

date of the subjects’ measurement period. Given that the ART initiation dates and

resultant 24 measurement periods vary by subject (see Figure 4.1), potential systematic

changes to Medicaid payments over time have the potential to render any differences in

total healthcare expenditures between adherence and non-adherence groups biased.

Therefore, it was necessary to test whether the 24 month measurement periods for the

two groups of interest, ART adherent (>90% MPR) and non-adherent (<90% MPR),

spanned significantly different periods in time.

The mean ART start date for the HIV-positive group combined was October 2,

2007 (n=270). For the HIV-positive group, there was a 33 day difference in ART

initiation between the ART adherence group and the non-ART adherence group. Based

on a two sample t-test procedure of the groups’ antiretroviral start dates, no significant

statistical difference existed between mean start dates for the groups (t= -1.25, p=0.2137).

The mean ART start date for the AIDS-positive group combined was May 18,

2008 (n=232). Based on a two sample t-test procedure of the groups’ antiretroviral start

dates, no significant statistical difference between mean start dates for the groups (t= .70,

p=0.4825).

Figure 4.2 shows that the median antiretroviral start month was January 2008; the

mode start date was July 2007.

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Figure

Data cleaning

Florida Medicaid contracts with

activities for some AIDS-

managed care) payment system, called the Florida Medicaid Project AIDS Care (PAC).

Unfortunately, the data for PAC waiver enrollment was not included in the files for fiscal

years 2009 through 2011. Figure

procedure codes and PAC enrollment declined in later years of the measurement study.

As a result of this data issue, a variable that controlled for these services was not included

in the research models.

46

Figure 4.2: First month of ART (n=514)

Florida Medicaid contracts with a company to conduct disease management

-diagnosed individuals enrolled in the fee-for-service (non

managed care) payment system, called the Florida Medicaid Project AIDS Care (PAC).

Unfortunately, the data for PAC waiver enrollment was not included in the files for fiscal

9 through 2011. Figure 4.3 demonstrates how claims for case management

procedure codes and PAC enrollment declined in later years of the measurement study.

As a result of this data issue, a variable that controlled for these services was not included

company to conduct disease management

service (non-

managed care) payment system, called the Florida Medicaid Project AIDS Care (PAC).

Unfortunately, the data for PAC waiver enrollment was not included in the files for fiscal

.3 demonstrates how claims for case management

procedure codes and PAC enrollment declined in later years of the measurement study.

As a result of this data issue, a variable that controlled for these services was not included

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Figure 4.3: Project AIDS Care enrollment or case management

Codes regarding provider specialty code were only included for less than 5% of

the sampled claims; therefore, an HIV specialist and infectious disease

variable that controlled for expertise of a treating physician was not included in the

research models.

Cognitive therapy has been found to be an important factor (Safren et al., 2009) in

improving adherence to ART. In the Medicaid data obta

lacked procedure codes for most of the outpatient claims. Therefore, an outpatient mental

health variable that controlled for the impact of cognitive therapy was not included in the

research models.

Lab data (LOINC) were included

data (July 2006-June 2008

below, the impact of the missing expenditure data would not bias either the high

adherence group or the low adherence grou

Also, Table 4.1 shows that the values for lab claims

high adherence (>90% M

47

: Project AIDS Care enrollment or case management services claims by year

Codes regarding provider specialty code were only included for less than 5% of

the sampled claims; therefore, an HIV specialist and infectious disease physician type

variable that controlled for expertise of a treating physician was not included in the

Cognitive therapy has been found to be an important factor (Safren et al., 2009) in

improving adherence to ART. In the Medicaid data obtained from AHCA, the files

lacked procedure codes for most of the outpatient claims. Therefore, an outpatient mental

health variable that controlled for the impact of cognitive therapy was not included in the

Lab data (LOINC) were included in the data set for the early fiscal years of the

June 2008), but not later years (July 2008-June 2011). As discussed

below, the impact of the missing expenditure data would not bias either the high

adherence group or the low adherence group, therefore, the data were kept in the analysis.

.1 shows that the values for lab claims were small and comparable between

90% MPR) and non-adherence groups (<90 MPR), on average.

: Project AIDS Care enrollment or case management

Codes regarding provider specialty code were only included for less than 5% of

physician type

variable that controlled for expertise of a treating physician was not included in the

Cognitive therapy has been found to be an important factor (Safren et al., 2009) in

ined from AHCA, the files

lacked procedure codes for most of the outpatient claims. Therefore, an outpatient mental

health variable that controlled for the impact of cognitive therapy was not included in the

in the data set for the early fiscal years of the

). As discussed

below, the impact of the missing expenditure data would not bias either the high

p, therefore, the data were kept in the analysis.

small and comparable between

0 MPR), on average.

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48

TABLE 4.1: Descriptive statistics for monthly laboratory expenditures in 24 month measurement period (n=435)

n mean sd minimum maximum < 90% MPR 326 $35.13 $61.39 $0.00 $627.28 > 90% MPR 109 $34.26 $46.28 $0.00 $166.88

In addition, as shown in Table 4.2, among laboratory utilizers (n=249), there was little

difference in the mean expenditures between ART adherence groups.

TABLE 4.2: Descriptive statistics for monthly laboratory expenditures for subjects averaging greater than $0 in 24 month measurement period (n=249)

n mean sd minimum maximum < 90% MPR 188 $60.92 $70.50 $0.24 $627.28 > 90% MPR 61 $61.22 $46.66 $0.24 $166.88

None of the 514 subjects were diagnosed with somatoform disorder. As such, this

diagnosis was removed from the variable that included diagnoses of depression and

anxiety.

As demonstrated by Gardner et al. (2008), discounted generic antiretroviral drug

pricing significantly impacts the relationship of adherence to ART to the total

expenditures, as the generics may be less than 10% of the prices of non-generic ART

medications. Among the sample of this research, only five individuals were prescribed

generic medications, as noted in Table 4.3. As a result of the small sample size, subjects

taking generic ART were not included as a model variable.

Among those subjects that filled generic ART medications, the generics were a

minority of the other antiretroviral drugs (1.7% to 26.7%), as shown in Table 4.3.

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49

TABLE 4.3: Descriptive statistics for Medicaid-insured previously ART-naïve PLWHA whose antiretroviral therapy (ART) includes generic medications (n=5)

Subject Generic ART Frequency Total ART

Prescriptive Fills % of Subject's ART

Prescriptions

Subject 1 Zidovudine 30 mg 10 40 25.0% Subject 2 Zidovudine 30 mg 8 30 26.7% Subject 3 Zidovudine 30 mg 1 60 1.7% Subject 4 Zidovudine 30 mg 10 79 12.7% Subject 5 Didanosine 250 mg 14 104 13.5%

Additionally, those subjects with generic ART claims were all found in the non-adherent

group (<90% MPR). Table 4.4 shows that the mean MPR for the five subjects was 33%.

TABLE 4.4: Descriptive statistics for medication possession ratio among Medicaid-insured PLWHA whose antiretroviral therapy (ART) included generic medications (n=5) n mean sd minimum maximum Medication possession ratio 5 0.33 0.15 0.16 0.53

Finally, the mean total expenditures for the five subjects using generic

medications was $2,461, although there was substantial variation, as Table 4.5 shows.

Nonetheless, the mean for this generic antiretroviral medication group was 30% higher

than the mean for the subjects in the non-adherent group (<90%) as a whole ($1,886).

TABLE 4.5: Descriptive statistics for total healthcare expenditure among Medicaid-insured previously ART-naïve PLWHA whose antiretroviral therapy (ART) included generic medications (n=5)

n mean sd minimum maximum Total healthcare expenditures 5 $2,461 $2,666 $344 $6,790

While a fully automated de-duplication was processed on the entire claims file,

some duplicate inpatient claims remained in the system. In some instances, hospitals

submitted two claims for the same date span, but for slightly different amounts. Under

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50

Medicaid claims payment policy, payments were made on a per diem basis, so duplicate

claims for the same days were disallowed. In these cases, the duplicates were removed.

Objective 1: Descriptive results

Objective 1 assessed the independent determinants of non-adherence to ART

among treatment-naïve PLWHA using retrospective Florida Medicaid claims data. As

discussed above, the final sample for this objective was 514 individuals. All subjects

were ART treatment naïve for 12 months prior to the 24 months measurement period.

Each subject was categorized into one of two groups according to their

medication possession ratio (MPR), a measure of their adherence to ART, as discussed in

the Methods section above.

TABLE 4.6: Frequency of previously ART-naïve Medicaid-insured PLWHA in antiretroviral therapy "adherence" and "non-adherence" categories as measured by possession ratio (MPR) in 24 month measurement period (n=514)

n % > 90% MPR 109 21% < 90% MPR 405 79% All subjects 514 100%

As shown in Table 4.6 above, 109 subjects had an MPR of 90% or greater and

were categorized as adherent; 405 subjects were below 90% MPR and were categorized

as non-adherent. Among the 514 PLWHA in the study, 21% were adherent to ART over

the 24 month measurement period, and 79% were non-adherent during that time span.

As shown in Table 4.7, the mean MPR for the adherent group was 96%, but only

46% for the non-adherent group. Overall, the mean MPR for PLWHA in the study was

56%.

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51

TABLE 4.7: Descriptive statistics for Medicaid-insured medication naïve PLWHA by adherence and non-adherence categories (n=514)

n mean sd minimum maximum

All subjects 514 0.56 0.31 0.004 1

> 90% MPR 109 0.96 0.04 0.90 1

< 90% MPR 405 0.46 0.25 0.004 0.89

Subjects’ ages were measured based on their age on July 1st of their ART

treatment naïve year. The overall mean age for all subjects was 39.2 years. Subjects in

this research were divided into three groups: 1) 18 to 34 years, 2) 35 to 49 years, and 3)

50 to 64 years. The allocation and proportion of the 514 subjects were categorized in each

age group as follows 167 (32.5%) in ages 18-34, 267 (53.7%) in ages 35-49, and 80

(15.6%) in ages 50-64.

TABLE 4.8: Descriptive statistics for age on July 1st of subjects' reference year (n=514)

n mean sd minimum maximum

All subjects 514 39.2 9.89 18 61

> 90% MPR 405 39.1 10.18 18 61

< 90% MPR 109 39.8 8.74 21 57

As shown in Table 4.8 above, the mean ages by adherence group equals 39.1

years and 39.8 for the adherent (>90%) and non-adherent (<90%) groups, respectively.

The distribution of MPR by age groups are presented in Table 4.9 below. On average, the

younger age group has a lower MPR than the two older groups of individuals.

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TABLE 4.9: Medication possession ratio (MPR) among previously ART

Florida Medicaid gathers race and ethnicity as a part of the eligibility and

enrollment process. Among 514 subjects in this

majority (58.8%) reported their race as black

Hispanic race or ethnicity, and 8%

Figure 4.4: ART Adherence category by race/ethnicity (n=514)

All 18 - 34> 90% MPR< 90% MPR

All 35 - 49> 90% MPR< 90% MPR

All 50 - 64> 90% MPR< 90% MPR

TABLE 4.9: Medication possession ratio (MPR) among previously ART-naïve Medicaid-insured PLWHA by age groups (n=514)

52

Medication possession ratio (MPR) among previously ART-naïve Medicaid-insured PLWHA by age groups (n=514)

Florida Medicaid gathers race and ethnicity as a part of the eligibility and

enrollment process. Among 514 subjects in this research, Figure 4.4 shows that the

majority (58.8%) reported their race as black, 20% reported as white, 13.2% reported as

race or ethnicity, and 8% other race, or not determined.

: ART Adherence category by race/ethnicity (n=514)

n mean sd minimummaximum

167 0.49 0.32 0.0032 0.95 0.04 0.90135 0.38 0.25 0.004

267 0.60 0.29 0.0459 0.97 0.03 0.90208 0.50 0.24 0.04

80 0.58 0.31 0.0418 0.98 0.03 0.9062 0.47 0.26 0.04

Age Group 3: 50-64 (n=80)

TABLE 4.9: Medication possession ratio (MPR) among previously ART-naïve Medicaid-insured PLWHA by age groups (n=514)

Age Group 1: 18-34 (n=167)

Age Group 2: 35-49 (n=267)

Florida Medicaid gathers race and ethnicity as a part of the eligibility and

shows that the

20% reported as white, 13.2% reported as

: ART Adherence category by race/ethnicity (n=514)

maximum

1.001.000.86

1.001.000.89

1.001.000.86

TABLE 4.9: Medication possession ratio (MPR) among previously ART-naïve Medicaid-insured PLWHA by age groups (n=514)

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53

Table 4.10 shows the relative proportion of blacks were non-adherent to ART in

the measurement period.

TABLE 4.10: Adherent (>90%) and non-adherent (<90%) proportions by race and ethnicity for Medicaid-insured previously antiretroviral naïve PLWHA (n=514) White Black Other Hispanic > 90% MPR 35% 18% 12% 21% < 90% MPR 65% 82% 88% 79%

Table 4.11 shows the distribution of MPR by adherence category by race and ethnicity

categories.

TABLE 4.11: Medication possession ratio (MPR) by race and ethnicity for Medicaid-insured previously antiretroviral naïve PLWHA (n=514)

There are two main eligibility categories in Florida Medicaid – Temporary

Assistance for Needy Families (TANF) and Social Security Income (SSI) (Agency for

n mean std dev minimum maximum

All 103 0.63 0.32 0.04 1.00> 90% MPR 36 0.96 0.04 0.90 1.00< 90% MPR 67 0.45 0.25 0.04 0.86

All 302 0.53 0.31 0.004 1.00> 90% MPR 54 0.96 0.04 0.90 1.00< 90% MPR 248 0.44 0.26 0.004 0.89

All 41 0.54 0.28 0.04 0.99> 90% MPR 5 0.96 0.02 0.95 0.99< 90% MPR 36 0.48 0.25 0.04 0.86

All 68 0.62 0.26 0.08 1.00> 90% MPR 14 0.97 0.04 0.90 1.00< 90% MPR 54 0.53 0.21 0.08 0.86

TABLE 4.11: Medication possession ratio (MPR) by race and ethnicity for Medicaid-insured previously antiretroviral naïve PLWHA (n=514)

Other races

White

Black

Hispanic race and ethnicity

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54

Health Care Administration, 2013a, 2013b). The income limit for a family of two (i.e.,

child and adult) to qualify for Florida Medicaid in 2013 was $1,138 per month for

eligibility under SSI rules and $1,293 per month under TANF eligibility rules. The assets

limits of approximately $2,000 in 2010 were also applicable for Medicaid eligibility. It is

important to note that for the Medicaid population in Florida, the relative affluence of a

county population at large does not reflect the individual Medicaid enrollee’s financial

resources. In fact, the income among all subjects is held relatively constant, in that low

income and assets are a requirement for Medicaid eligibility.

Table 4.12 shows that a majority of subjects (76%) were eligible for Medicaid

through the SSI program. The MPR means for both Medicaid eligibility categories was

56%.

TABLE 4.12: Medication possession ratio (MPR) by Medicaid eligibility category for PLWHA (n=514) n mean sd minimum maximum

TANF Medicaid Eligibility (n=123) All 123 0.56 0.31 0.004 1.00

< 90% MPR 97 0.45 0.25 0.00 0.86 > 90% MPR 26 0.96 0.04 0.90 1.00

SSI Medicaid Eligibility (n=391) All 391 0.56 0.31 0.03 1.00

< 90% MPR 308 0.46 0.25 0.03 0.89 > 90% MPR 83 0.96 0.03 0.90 1.00

Table 4.13 shows that similar proportions were divided among the ART adherent

and non-adherent categories. A chi-square test confirmed no significant difference in

frequencies between SSI-eligible subjects that were adherent compared to non-adherent,

nor any differences between TANF-eligible subjects in adherent versus non-adherent

categories (χ2=.0004, p=.98).

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55

TABLE 4.13: Medicaid eligibility categories by type and adherence category among previously ART-naïve Medicaid-insured PLWHA (n=514) < 90% (n=405) > 90% (n=109) Total n % n % n % Temporary Assistance for Needy Families (TANF)

97 24.0% 26 23.9% 123 23.9%

Social Security Income (SSI) 308 76.0% 83 76.1% 391 76.1%

Due to Agency for Health Care Administration data use agreement designed to

protect patient identity, county of residence is the smallest geographic identifier available

in the demographic files provided for this study. The U.S. Census Bureau defines an

urban county as containing a density equal to or greater than 100 people per square mile

(U.S. Census Bureau, 2013b). In Florida, there were 38 counties (56%) classified as

urban. A large majority of PLWHA subjects reside in urban counties (n=470, 91.4%), as

compared to rural counties (n=44, 8.6%). This proportion was approximately the same as

the 2013 Florida population living in urban counties (91.2%) but higher than the U.S.

urban population as a whole (81%) (U.S. Census Bureau, 2013b). In addition, the

proportion of PLWHA in the United States is predominantly urban (Vyavaharkar,

Glover, Leonhirth, & Probst, 2013). Table 4.14 shows the distribution of MPR for subject

in counties by rural and urban population density.

According to the U.S. Census Bureau, 2005-2009 American Community Survey

(2013a), the median household median income for Florida counties in 2010 was $43,326.

That is, half of the counties’ median incomes were below this amount and half were

above this amount. Table 4.15 below shows that subjects residing in high income

counties had lower mean than subjects residing in low income counties. See Appendix

Table A4 for the complete listing of counties.

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56

TABLE 4.14: Frequency and distribution of medication possession ratio (MPR) by county population density for Medicaid-insured previously ART naïve PLWHA (n=514)

n mean sd minimum maximum Rural Counties (< 100 persons per square mile)

All 44 0.63 0.34 0.04 1.00

> 90% MPR 15 0.96 0.04 0.90 1.00

< 90% MPR 29 0.46 0.29 0.04 0.86 Urban counties (> 100 persons per square mile)

All 470 0.56 0.30 0.004 1.00

> 90% MPR 94 0.96 0.04 0.90 1.00 < 90% MPR 376 0.46 0.25 0.004 0.89

TABLE 4.15: Frequency and distribution of medication possession ratio (MPR) by county median household income category for Medicaid-insured PLWHA (n=514)

n mean sd minimum maximum Low Median Household Income (< $43,326)

All 192 0.60 0.31 0.04 1.00

< 90% MPR 141 0.47 0.25 0.04 0.88

> 90% MPR 51 0.96 0.04 0.90 1.00 High Median Household Income (> $43,326)

All 322 0.54 0.30 0.004 1.00

< 90% MPR 264 0.45 0.25 0.004 0.89

> 90% MPR 58 0.96 0.04 0.90 1.00

Table 4.16 shows the frequency of subjects residing in urban/rural and upper

household income counties/lower household income counties. Few individuals in the

sample (n=15, 2.9%) reside in low income rural counties.

TABLE 4.16: Frequency of subjects residing in counties by median income (high versus low) and population density (urban versus rural) attributes (n=514)

Urban Rural Total n % n % n

Low median income counties 307 59.7% 15 2.9% 322 High median income counties 163 31.7% 29 5.6% 192 Total 470 91.4% 44 8.6% 514

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As illustrated in Figure

low median income counties

Figure 4.5

Among the 514 subjects in Objective 1, 234 were HIV

and 280 were diagnosed with AIDS (

fewer subjects diagnosed as HIV in the sample popul

Figure 4.6

Table 4.17 shows HIV/AIDS disease status by adheren

categories. Comparatively, HIV

0

50

100

150

200

250

300

350

57

As illustrated in Figure 4.5, a large proportion of subjects (over 62%) reside in

low median income counties - a majority of those subjects residing in urban counties.

.5: Frequency of subjects residing in counties by median income and population density

Among the 514 subjects in Objective 1, 234 were HIV-positive (n=234,

and 280 were diagnosed with AIDS (n=280, 54.5%). Figure 4.6 illustrates the relatively

fewer subjects diagnosed as HIV in the sample population.

.6: HIV or AIDS disease status by ART adherence

.17 shows HIV/AIDS disease status by adherent and non-adheren

categories. Comparatively, HIV-positive individuals have a slightly higher proportion of

57 52

177228

HIV AIDS

> 90% MPR < 90% MPR

234 280

.5, a large proportion of subjects (over 62%) reside in

a majority of those subjects residing in urban counties.

by

n=234, 45.5%)

.6 illustrates the relatively

: HIV or AIDS disease status by ART adherence

adherent

higher proportion of

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58

individuals categorized as adherent (>90%) than AIDS-diagnosed subjects, although

there is no statistical difference (χ2=2.55, p=.11).

TABLE 4.17: Proportion of HIV or AIDS disease status by adherence and non-adherence categories for Medicaid-insured previously ART naïve PLWHA (n=514)

HIV AIDS Total n % n % n

> 90% MPR 57 24.4% 52 18.6% 109 < 90% MPR 177 75.6% 228 81.4% 405

The differences in adherence to ART between subjects with HIV and AIDS is illustrated

in the overall mean MPR shown in Table 4.18. There is no statistical difference between

the mean MPR for AIDS-diagnosed subjects (55%) compared to HIV-positive

individuals (58%) (χ2=82.97, p=.54).

TABLE 4.18: Medication possession ratio (MPR) by HIV or AIDS disease status for Medicaid-insured previously ART naïve PLWHA (n=514)

n mean sd minimum maximum HIV

All 234 0.58 0.32 0.004 1.00

> 90% MPR 177 0.46 0.27 0.004 0.88

< 90% MPR 57 0.96 0.04 0.90 1.00

AIDS All 280 0.55 0.30 0.04 1.00

> 90% MPR 228 0.45 0.24 0.04 0.89

< 90% MPR 52 0.96 0.04 0.90 1.00

Primary care guidelines for the management of PLWHA recommend that cell

counts and low viral loads be monitored every 3 to 4 months to monitor for drug toxicity

and to assess response to ART (Aberg et al., 2009). To engage in outpatient care at the

recommended frequency in the 24 month measurement period, subjects should have at

least eight outpatient claims. Table 4.19 shows that over half of the 514 patients (n=277,

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59

53.9%) had eight or more outpatient claims. Only six subjects had no outpatient claims

during the 24 month measurement period; 61 subjects had 60 or more outpatient claims.

TABLE 4.19: Total and proportion of outpatient visits in 24 month measurement period among Medicaid-insured previously ART-naïve PLWHA (n=514)

Outpatient visits n % Zero outpatient visits 6 1.2% 1 to 2 203 39.5% 3 to 7 28 5.4% 8 to 19 74 14.4% 20 to 39 93 18.1% 40 to 59 49 9.5% 60 and more 61 11.9%

An increased number of antiretroviral medications used concurrently may be

related to lower ART adherence (Kleeberger et al., 2001; Maggiolo et al., 2005). Among

this sample, over 62% filled three to five ART medications in their first month of ART.

Among those subjects that filled only one ART medication prescription (n=106), 91

subjects (86%) filled AtriplaTM, a combination drug with three active medications,

including a non-nucleoside reverse transcriptase inhibitor (NNRTI) and two nucleoside

reverse transcriptase inhibitors (Julg & Bogner, 2008). There is a bivariate significant

difference between non-adherence (n=57, 14%) and adherent groups of (n=34, 31%)

subjects taking AtriplaTM as a single drug (2=17.27, p<0.001). The remaining 15

subjects filled prescription from single classes of drugs, such as integrase strand transfer

inhibitors (INSTI).

As shown in Table 4.20, a lower proportion of AIDS-diagnosed subjects filled

only a single antiretroviral medication (ARV), as compared to those without an AIDS

diagnosis. A higher proportion of AIDS-diagnosed subjects (21.4%) filled six or more

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60

concurrent medications in the first month of ART initiation, as compared to those without

an AIDS diagnosis (10.3%).

TABLE 4.20: Number of concurrent ARV medications filled in the first month of ART initiation by HIV or AIDS status among previously ART-naïve Medicaid-insured PLWHA (n=514)

HIV (n=234) AIDS (n=280) Total n % n % n

1 (reference) 63 26.9% 43 15.4% 106 2 44 18.8% 41 14.6% 85 3 to 5 103 44.0% 136 48.6% 239 6 or more 24 10.3% 60 21.4% 84

The most common ART regimen among the 514 subjects was boosted protease

inhibitors (50.6%), followed by NNRTI regimen (41.8%). Of the 39 subjects (7.6%) in

the single ART drug class category, 11 took INSTI class medications, 2 were on a

“nucleoside-sparing” regimen. A “nuc-sparing” regimen is designed to solve certain side-

effects associated with ART by removing NNRTI class of medications (Tebas et al.,

2007). The remaining 26 subjects filled a single drug class in their first month of ART

(four of these subjects filled multiple prescriptions in the same class). Drug regimens

were measured in the first month of the measurement period. Additional drug classes

could have been added to the single drug regimen, or the regimen could have changed

over the 24 month measurement period.

While the burden associated with adverse drug reactions (ADR) associated with

ART has lessened with the development of new drugs, no ADR-free ART regimens exist

(Johnson, Dilworth, Taylor, & Neilands, 2010). There were common ADR associated

with ART, such as symptoms involving digestive system (Johnson et al., 2010; Wohl et

al., 2006), abnormal glucose levels of the blood, lactic acidosis (Wohl et al., 2006),

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61

lipodystrophy, visual disturbances, anorexia (Ammassari et al., 2001), dyslipidemia,

dizziness and skin disorders (Rudorf, 2005).

TABLE 4.21: ART-related adverse drug reactions among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514)

As shown in Table 4.21 above, the most prevalent diagnosis category among

commonly identified ADR involved the digestive system (51.6%), such as nausea,

diarrhea, and vomiting. The other common ADR was dyslipidemia, an abnormal amount

of lipids (e.g., cholesterol and/or fat) in the blood. Dyslipidemia has been shown to be

associated with advanced HIV disease in the absence of ART and a consequence of ART

medications (Wohl et al., 2006). Among the 514 subjects in this research, dyslipidemia

was more prevalent in the ART adherent group (56.0%) than in the non-adherent group

(35.8%); a bivariate comparison of the proportions between the groups (<90% versus

>90%) was significant for dyslipidemia (p<0.01). All other bivariate comparisons of

ADR were non-significant.

Among common chronic diseases among HIV-positive individuals, there was no

significant differences between ART non-adherent and ART adherent groups, as shown

Totaln % n % χ2

Symptoms involving digestive system (e.g., nausea and diarrhea)

209 51.6% 56 51.4% 265

Dyslipidemia 145 35.8% 61 56.0% ** 206Dizziness 44 10.9% 15 13.8% 59Visual disturbances 26 6.4% 11 10.1% 37Skin disorders (e.g., rashes and dyschromia)

29 7.2% 6 5.5% 35

Lactic acidosis 23 5.7% 2 1.8% 25Abnormal glucose 14 3.5% 5 4.6% 19Lipodystrophy 11 2.7% 3 2.8% 14Anorexia 11 2.7% 3 2.8% 14

TABLE 4.21: ART-related adverse drug reactions among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514)

< 90% > 90%

*** < 0.001; ** <0.01; * <0.05

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62

in Table 4.22. Over 69% of subjects had at least one comorbidity. Interestingly, there was

a significant bivariate difference between those with at least one chronic disease and

meeting the average recommended minimum number of outpatient visits (2=4.57,

<.05). However, it is unclear as to the direction of this relationship – outpatient visits

leading to diagnoses or diagnoses causing more outpatient visits.

TABLE 4.22: Chronic diseases among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514)

Finally, among the 514 subjects, 269 (52%) were diagnosed with HIV in the first

month of ART initiation. During the 24 month measurement period, 35 of those subjects

(13%) were diagnosed with an AIDS-defining illness.

Objective 1: Unadjusted logistic regression results

Table 4.23 shows variable proportions organized by ART adherent (>90% MPR)

and ART non-adherent (<90% MPR) categories. Also, Table 4.23 shows the unadjusted

logistic regression analysis for the model variables testing for differences between

adherent (>90% MPR) and non-adherent (<90%) groups.

Totaln % n % χ2

Hypertension 176 43.5% 54 49.5% 230COPD 103 25.4% 33 30.3% 136Hepatitis C 99 24.4% 23 21.1% 122Diabetes 85 21.0% 21 19.3% 106Asthma 65 16.0% 23 21.1% 88Chronic ischemic heart disease, cardiac insufficiency and MI

48 11.9% 14 12.8% 62

Osteoarthritis 40 9.9% 15 13.8% 55Chronic kidney disease 39 9.6% 7 6.4% 46Shingles 24 5.9% 4 3.7% 28Peripheral Neuopathy 23 5.7% 3 2.8% 26

*** < 0.001; ** <0.01; * <0.05

TABLE 4.22: Chronic diseases among Medicaid-insured previously antiretroviral-naïve PLWHA by adherence categories (n=514)

< 90% > 90%

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63

TABLE 4.23: Descriptive statistics for Medicaid-insured previously antiretroviral-naïve PLWHA by non-adherent (<90%) and adherent (>90%) categories (n=514)

n % n % χ2 n %

Age groups18–34 135 33.3% 32 29.4% 167 32.5%35–49 208 51.4% 59 54.1% 267 51.9%50 years or older (reference) 62 15.3% 18 16.5% 80 15.6%

SexMale 124 30.6% 43 39.4% 167 32.5%Female (reference) 281 69.4% 66 60.6% 347 67.5%

Race/Ethnicity **White race, non-Hispanic (reference) 67 16.5% 36 33.0% 103 20.0%Black race, non-Hispanic 248 61.2% 54 49.5% 302 58.8%Other race, non-Hispanic 36 8.9% 5 4.6% 41 8.0%Hispanic race and/or ethnicity 54 13.3% 14 12.8% 68 13.2%

Counties by Median Income *Low Median Income 141 34.8% 51 46.8% 192 37.4%High Median Income 264 65.2% 58 53.2% 322 62.6%

Population density *Rural 29 7.2% 15 13.8% 44 8.6%Urban 376 92.8% 94 86.2% 470 91.4%

Medicaid Eligiblity CategoryTANF 97 24.0% 26 23.9% 123 23.9%SSI 308 76.0% 83 76.1% 391 76.1%

Eligibility for MedicaidContinuous Enrollment (reference) 348 85.9% 100 91.7% 448 87.2%Gap 1 to 3 months within one year 57 14.1% 9 8.3% 66 12.8%

ART regimen **Boosted protease inhibitor 221 54.6% 39 35.8% 260 50.6%NNRTI 155 38.3% 60 55.0% 215 41.8%Other antiretroviral classes 29 7.2% 10 9.2% 39 7.6%

Number of concurrent ARV medications ***1 (reference) 66 16.3% 40 36.7% 106 20.6%2 67 16.5% 18 16.5% 85 16.5%3 to 5 197 48.6% 42 38.5% 239 46.5%6 or more 75 18.5% 9 8.3% 84 16.3%

Meeting minimum outpatient recommendations< 4 annual outpatient visits mean 189 46.7% 48 44.0% 237 46.1%> 4 annual outpatient visits mean 216 53.3% 61 56.0% 277 53.9%

< 90% (n=405)> 90% (n=109) Total

TABLE 4.23: Descriptive statistics for Medicaid-insured previously antiretroviral-naïve PLWHA by non-adherent (<90%) and adherent (>90%) categories (n=514)

*** < 0.001; ** <0.01; * <0.05

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In Table 4.23 above, race/ethnicity had significantly different proportion of

adherence groups (χ2=14.65, p<0.01). Geographic factors were also significantly

different between adherent and non-adherent groups - median income county residence

(χ2=5.16, p<0.05) and rural/urban county residence (χ2=4.30, p<0.05). Among ART

related factors, regimen types (χ2=12.34, p<0.01), and the number of concurrent ARV

medications (χ2=23.46, p<0.01) were significantly different between adherent and non-

adherent groups. As for clinical factors, chronic disease diagnosis (χ2=4.12, p<0.05),

more/less than 2 antidepressant prescription claims (χ2=3.90, p<0.05), and adherence to

antidepressants (χ2=15.73, p<0.001) were statistically different by adherence groups. The

Objective 1 bivariate analysis indicated no statistical differences between adherent and

non-adherent categories for age groups, sex, Medicaid eligibility category, discontinuous

n % n % χ2 n %

HIV/AIDS statusHIV (reference) 177 43.7% 57 52.3% 234 45.5%AIDS 228 56.3% 52 47.7% 280 54.5%

Disease Progression 28 12.3% 7 13.5% 35 12.5%Non-HIV chronic disease diagnoses *

No other chronic disease diagnosis 133 32.8% 25 22.9% 158 30.7%1 or more non-HIV chronic diagnosis 272 67.2% 84 77.1% 356 69.3%

Mental Illness ComorbiditiesDepression and/or anxiety diagnosis 107 26.4% 28 25.7% 135 26.3%Substance abuse and/or alcohol abuse 42 10.4% 9 8.3% 51 9.9%Severe mental illness 50 12.3% 15 13.8% 65 12.6%

Antidepressant Regimen *Less than 2 antidepressant 214 52.8% 46 42.2% 260 50.6%2 or more antidepressant prescription 191 47.2% 63 57.8% 254 49.4%

Adherent to antidepressants ***<80% antidepressant MPR 126 66.0% 26 41.3% 152 29.6%>80% antidepressant MPR 65 34.0% 37 58.7% 102 19.8%

< 90% (n=405)> 90% (n=109) Total

Continued, TABLE 4.23: Descriptive statistics for Medicaid-insured previously antiretroviral-naïve PLWHA by non-adherent (<90%) and adherent (>90%) categories

*** < 0.001; ** <0.01; * <0.05

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enrollment in Medicaid, HIV/AIDS status, meeting recommended minimum number of

average outpatient visits, depression and/or anxiety diagnosis, substance abuse and/or

alcohol abuse, and severe mental illness.

Objective 1: Model diagnostics

Multiple independent variables were analyzed for their association with ART non-

adherence, including demographic, diagnoses, insurance, and healthcare service

utilization factors. Logistic regression was used to predict a binary dependent variable -

non-adherence to ART (versus adherence to ART). All model independent variables

contain complete separation of groups (no overlaps of categories).

Moderate multicollinearity (0.54) exists between NNRTI antiretroviral regimen

and 3 to 5 concurrent medications drugs in the regimen. Other multicollinearity exists

between variables in mutual exclusive categories (e.g., chronic disease levels). No

variance inflation scores were above 2.6, also indicating a lack of multicollinearity.

The logistic regression models used in this research were adequate for unbiased

estimation, based on simulation of sample size adequacy run by Vittinghoff &

McCulloch (2007) showing that 10 outcomes per independent variable rule of thumb may

be too conservative. The full logistic regression model for this research contains over 21

outcomes per independent variable (n=514 / IVs=24). Also, Hosmer and Lemeshow

(2004) recommend a sample size for logistic regression of greater than 400, a

requirement satisfied by the sample size of 514. Also, there were no linearity of logit

issues nor any outlier problems. Finally, the requirement that no more than 20% of the

expected counts of 5 or less for the chi-square contingencies was satisfied (Cochran,

1954).

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Hosmer-Lemeshow goodness-of-fit assessment tests the null hypothesis that there

was no difference between the observed and predicted values of the dependent variable of

non-adherence to ART (Hosmer & Lemeshow, 2004). For the full logistic model

described below, the null hypothesis was not rejected (χ2=4.04, p=0.85), so the model fits

the data. The reduced logistic regression model also fits the data (χ2=12.37, p=0.14).

Also, the more parsimonious model improves the Akaike’s Information Criterion (AIC),

naturally, as AIC penalizes for the addition of parameters (Hosmer & Lemeshow, 2004).

The full model AIC equals 504.51; the reduced model AIC equals 493.90.

One method for evaluating a logistic regression model fit is to determine the

influence of outliers on the prediction through a plot of the residual deviances (Pardoe &

Cook, 2002). Analysis of the residual deviation was plotted in Figure 4.7 showing that

the full logistic regression model fits reasonably well. The circles on the top represent the

prediction of the low adherence group, and the circles on the bottom represent the

prediction of the high adherence group Figure 4.7 shows that the prediction error was

more pronounced for the ART adherent (>90%) group illustrated below the line in red,

but that the residuals fall within ± 3 standard deviations.

Figure 4.7: Model Fit Chart of Deviance Residual

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Objective 1: Logistic model results

Objective 1 full model. Objective 1 assessed the independent determinants of

non-adherence to ART among Medicaid-insured previously treatment-naïve PLWHA.

Given that the dependent variable (non-adherence versus adherence) was dichotomous, a

multivariable logistic regression model was built.

In the full logistic regression model shown in Table 4.23 below, individuals

classified as black race, non-Hispanic ethnicity were found to have over 2.3 times the

odds (OR=2.31, 95% CI=1.28-4.18, p<.01) of being classified as non-adherent to ART

(<90% MPR), as compared to their white counterparts. The other race classification

subjects (Asian, American Indian, Alaskan Native, or not determined) were also

significantly more likely to be non-adherent to ART compared to whites (OR=3.13,

CI=1.03-9.48, p<.05). In the full model, subjects reported as Hispanic race and/or

ethnicity were also statistically significantly associated with being classified as non-

adherent to ART (OR 2.37, CI=1.05-5.34, p<.05).

As compared to individuals taking a single antiretroviral medication, individuals

filling three to five ART medications had over twice the odds of non-adherence

(OR=2.04, 95% CI=1.04-4.01, p<.05); and subjects with six or more ART medications

were 4.58 times the odds of being non-adherent (95% CI=1.82-11.56, p<.01), as

compared to those taking only a single ART medication. The number of concurrent

medications in the ART regimen was a moderator for regimen types included in the

model. When the number of concurrent medications were removed from the model, those

taking NNRTI-based regimens have 53% higher odds of being adherent, as compared to

protease inhibitor based regimens (OR=.47, 95% CI=.29-.76, p<.01). Adverse drug

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reactions (ADR), lessens the effect size of the number of concurrent medications in ART

variables, but does not change their significance in the model. Also, existence of ADR do

not impact regimen type when number of concurrent ART medications were removed

from the model.

TABLE 4.24: Full logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514)

Effect Odds Ratio χ2

Age Groups18-34 0.808 0.363 1.79935-49 0.826 0.416 1.63950 years or older (reference) - - -

SexFemale (reference) - - -Male 0.682 0.401 1.159

Race and EthnicityWhite (reference) - - -Black race non-hispanic 2.309 1.276 4.179 **Other race, non-hispanic 3.128 1.031 9.484 *Hispanic race and/or ethnicity 2.367 1.049 5.341 *

Counties by Median IncomeLow Median Income - - -High Median Income 1.892 0.876 4.088

Population densityRural - - -Urban 1.623 0.988 2.668

Eligibility for MedicaidContinuous Enrollment - - -Gap 1 to 3 months in a year 1.74 0.781 3.874

Medicaid Eligiblity CategoryTANF - - -SSI 1.535 0.822 2.869

ART RegimenBoosted protease inhibitor - - -Non-nucleoside reverse transcriptase inhibitor 0.694 0.383 1.257Other antiretroviral classes (INSTI, nucleocide sparing and single ART)

0.824 0.32 2.122

Number of Concurrent ARV Medicines1 (reference) - - -2 1.889 0.892 4.0043 to 5 2.04 1.037 4.013 *6 or more 4.58 1.815 11.556 **

95% Confidence Limits

Table 4.24: Full logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514)

*** < 0.001; ** <0.01; * <0.05

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As compared to those subjects with no chronic disease diagnoses, subjects with

one or more non-HIV chronic disease (see Table 4.21) have 54% higher odds of

adherence to ART (OR=.46, 95% CI=.26-.84, p<.01). The association of chronic disease

one or more non-HIV chronic disease to ART adherence persisted with the inclusion of

the “meeting minimum recommended average outpatient visits” variable in the model.

Meeting minimum recommended average outpatient visits was defined as meeting the

minimum recommended outpatient care visits requirement (mean of greater than or equal

to 4 annually). In addition, the significance and effect size of non-HIV chronic disease to

ART adherence persisted when outpatient utilization was measured on a continuous scale

(not included here).

Finally, among those subjects with two or more antidepressant medication refills,

those that were adherent to their antidepressants (greater than or equal to 80% medication

Effect Odds Ratio χ2

Meeting minimum outpatient recommendations< 4 annual outpatient visits mean (reference) - - -> 4 annual outpatient visits mean 0.748 0.436 1.283

HIV/AIDS StatusHIV (reference) - - -AIDSDisease Progression 0.975 0.366 2.602

Non-HIV chronic disease diagnosesNo other chronic disease diagnosis - - -1 or more non-HIV chronic disease diagnosis 0.464 0.257 0.836 **

Mental Illness ComorbiditiesDepression or anxiety diagnosis 1.308 0.706 2.423Substance abuse and/or alcohol abuse 1.127 0.46 2.763Severe mental illness 1.682 0.766 3.691

Antidepressant RegimenLess than 2 antidepressant prescription claims - - -2 or more antidepressant prescription claims 0.821 0.473 1.422

<80% antidepressant MPR - - ->80% antidepressant MPR 0.276 0.142 0.537 **

95% Confidence Limits

Continued, Table 4.24: Full logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514)

*** < 0.001; ** <0.01; * <0.05

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possession ratio) have 72% greater odds of adherence to ART than those non-adherent to

antidepressants (OR=.28, 95% CI=.14-.54, p<.01).

Objective 1 reduced model. In the reduced model shown in Table 4.25,

individuals classified as black race, non-Hispanic ethnicity were found to have twice the

odds (OR=2.00, 95% CI=1.16-3.45, p<.01) of being classified as non-adherent to ART,

as compared to whites.

TABLE 4.25: Reduced logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514) (n=514)

Also in Table 4.25 above, the reduced logistic model results show that the other

race classification had 3.32 times higher odds of being non-adherent to ART (OR=3.32,

CI=1.14-9.67, p<.05). Hispanic race and/or ethnicity had a non-significant association to

non-adherence to ART. Individuals living in urban counties in Florida had over two times

Effect Odds Ratio χ2

Race and EthnicityWhite (reference) - - -Black race non-Hispanic 2.00 1.16 3.45 *Other race, or not determined, non-Hispanic 3.32 1.14 9.67 *Hispanic race and/or ethnicity 2.02 0.94 4.33

Population densityRural - - -Urban 2.19 1.05 4.56 *

Number of Concurrent ARV Medicines1 (reference) - - -2 2.39 1.20 4.76 *3 to 5 2.88 1.67 4.95 **6 or more 6.68 2.88 15.49 ***

Non-HIV chronic disease diagnosesNo other chronic disease diagnosis - - -1 or more non-HIV chronic diagnosis 0.57 0.33 0.96 *

Antidepressant Regimen (2 or more claims)<80% antidepressant MPR - - ->80% antidepressant MPR 0.38 0.22 0.64 **

*** < 0.001; ** <0.01; * <0.05

95% Confidence Limits

Table 4.25: Reduced logistic regression model predicting non-adherence (<90% MPR) to antiretroviral therapy among previously ART-naïve Medicaid-insured PLWHA (n=514)

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higher odds of being classified in the low ART adherence group (OR=2.19, 95%

CI=1.01-2.64, p<.05), as compared to those living in rural counties. High/low median

income county of residence was made non-significant by inclusion of the rural counties

variable.

As compared to individuals taking a single antiretroviral therapy medication,

individuals taking two ART medications were found to have over 2.3 times the odds

(OR=2.39, 95% CI=1.20-4.76, p<.05) of being classified as non-adherent to ART (<90%

MPR). Additionally, subjects filling three to five ART medications had almost 2.9 times

the odds of non-adherence (OR=2.88, 95% CI=1.67-4.95, p<.01); and subject with six or

more ART medications were 6.7 times as likely to be non-adherent (OR=6.68, 95%

CI=2.88-15.49, p<.001), as compared to those taking only a single ART. When the

number of concurrent medications were removed from the reduced model, those taking

NNRTI-based regimens have 57% higher odds of being adherent, as compared to

protease inhibitor based regimens (95% CI=.26-.69, p<.01). Adverse drug reactions

lessens the effect size of the number of concurrent medications in ART variables, but

does not change their significance in the model. Also, existence of ADR do not impact

regimen type variable significance in the model when numbers of concurrent ART

medications were removed.

Also, non-HIV chronic diseases play a statistically significant part of predicting

non-adherence to ART. As compared to those with no chronic disease diagnoses, subjects

with at least one chronic disease diagnosis were 43% less likely to be classified as non-

adherent to ART (OR=0.57, 95% CI=.33-.96, p<.05). The existence of one or more ADR

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lessens the coefficient of non-HIV chronic diseases, but does not change the significance

in the model.

Finally, subjects with two or more antidepressant medication refills do not have

significantly different odds of non-adherence to ART, as compared to those with one or

less antidepressant medication refills. However, among subjects with two or more

antidepressant medication refills, those with greater than or equal to 80% medication

possession ratio were 62% less likely to be classified as non-adherent (OR=0.38, 95%

CI=.22-.64, p<.01).

Objective 2: Descriptive results

Objective 2 modeled the mean monthly total healthcare expenditures for the

measurement period of those PLWHA in the ART non-adherent group (<90%) as

compared to the ART adherent group (>90%), controlling for demographic, clinical and

healthcare utilization factors. The Objective 2 sample of 502 subjects by HIV and AIDS

disease status and adherence group is shown in Table 4.26.

TABLE 4.26: Proportion of HIV or AIDS disease status by adherence and non-adherence categories for Medicaid-insured previously ART naïve PLWHA (n=502)

HIV (n=232) AIDS (n=270) Total Total n % n % n %

> 90% MPR 56 52.3% 51 47.7% 107 21.3% < 90% MPR 176 44.6% 219 55.4% 395 78.7%

The mean total healthcare expenditures for Florida Medicaid among PLWHA was

the outcome variable of Objective 2. The unadjusted mean monthly per subject total

healthcare expenditures for the 24 month period for the overall sample (n=502) was

$1,875. Figure 4.7 shows the mean unadjusted monthly total healthcare expenditures for

the non-adherent group (n=395) was $1,847; the unadjusted mean monthly total

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healthcare expenditures for the adherent group (n=107) was $1,976. An examination of

the expenditure components confirms that the adherent group had higher mean ART

pharmacy costs ($849 versus $445), but lower mean inpatient costs ($324 versus $745),

as compared to the non-adherent group.

Figure 4.8: Unadjusted mean monthly total healthcare expenditures by ART adherence category

Table 4.27 lists the mean total healthcare expenditures by category and the

relative proportions for the non-adherent and adherent groups and the overall means. TABLE

4.27: Unadjusted mean monthly total healthcare expenditures by category among Medicaid-insured ART-naïve PLWHA and antiretroviral therapy adherence category (n=502)

$418 $502

$745$324

$184

$279

$445 $849

$56$21

$0

$500

$1,000

$1,500

$2,000

$2,500

Non-adherent (n=395) Adherent (n=107)

Outpatient Inpatient Rx (Non-ART) ART Rx BH Inpatient

mean % mean % mean %Outpatient $418 22.6% $502 25.4% $436 23.3%Inpatient $745 40.3% $324 16.4% $655 34.9%Rx (Non-ART) $184 10.0% $279 14.1% $205 10.9%ART Rx $445 24.1% $849 43.0% $531 28.3%BH Inpatient $56 3.0% $21 1.1% $48 2.6%

Non-adherent (<90% MPR; n=232)

Adherent MPR (>90% MPR; n=107)

Total

TABLE 4.27: Unadjusted mean monthly total healthcare expenditures by category among Medicaid-insured ART-naïve PLWHA and antiretroviral therapy adherence category (n=502)

$1,847 $1,976

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As shown in Figure 4.9, the mean monthly total healthcare expenditures vary

greatly between HIV-positive ($1,439) and AIDS-diagnosed subjects ($2,250). The

unadjusted mean monthly ART pharmacy expenditures for HIV-positive were $497 and

$560 for AIDS-diagnosed subjects. The unadjusted mean monthly inpatient expenditures

for HIV-positive were $318, and $944 for AIDS-diagnosed subjects.

Figure 4.9: Unadjusted mean monthly total healthcare expenditures by HIV/AIDS status by ART adherence category

Figure 4.10 shows that the lowest unadjusted mean monthly total healthcare

expenditure group was non-adherent HIV-positive individuals ($1,280), and the highest

was the non-adherent AIDS-diagnosed subjects ($2,017). Separate linear regression

models for the HIV-positive and AIDS diagnosed groups were developed.

$401 $467

$318

$944$162

$241

$497

$560

$61

$38

$0

$500

$1,000

$1,500

$2,000

$2,500

HIV (n=232) AIDS (n-270)

Outpatient Inpatient Rx (Non-ART) ART Rx BH Inpatient

$1,439

$2,250

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Figure 4.10: Unadjusted mean monthly total healthcare expenditures by ART adherence category

Table 4.28 and Table 4.29 show the unadjusted mean monthly healthcare

expenditures and the relative proportion for HIV-positive and AIDS-diagnosed subjects,

respectively. The unadjusted mean monthly inpatient expenditures for non-adherent

AIDS-diagnosed subjects ($1,084) were almost three times the mean expenditures for the

adherent AIDS-diagnosed group ($341). The unadjusted mean ART expenditures for the

AIDS-diagnosed adherent group ($946) was about twice the mean expenditures for the

non-adherent AIDS group ART expenditures ($470).

TABLE 4.28: Monthly expenditures by category for HIV-positive subjects by adherence category (n=232)

Non-adherent (<90%;

n=176) Adherent (>90%;

n=56) mean % mean % Outpatient $329 25.7% $628 32.4% Inpatient $322 25.1% $309 15.9% Rx (Non-ART) $147 11.5% $210 10.8% ART Rx $413 32.2% $761 39.3% BH Inpatient $70 5.5% $30 1.6%

Total $1,280 100% $1,938 100%

$329$628 $490 $365

$322

$309

$1,084

$341$147

$210

$215

$354$413

$761

$470

$946

$70

$30

$44

$11

$0

$500

$1,000

$1,500

$2,000

$2,500

<90% MPR HIV (n=176)

>/90% MPR HIV (n=56)

<90% MPR AIDS (n=219)

>/90% MPR AIDS (n=51)

Outpatient Inpatient Rx (Non-ART) ART Rx BH Inpatient

$1,938

$2,304$2,017

$1,280

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TABLE 4.29: Monthly expenditures by category for AIDS-diagnosed subjects by adherence category (n=270)

Non-adherent (<90%;

n=219) Adherent (>90%;

n=51) mean % mean %

Outpatient $490 21.3% $365 18.1% Inpatient $1,084 47.1% $341 16.9% Rx (Non-ART) $215 9.3% $354 17.5% ART Rx $470 20.4% $946 46.9% BH Inpatient $44 1.9% $11 0.6%

Total $2,304 100% $2,017 100%

Covariate factors by adherence group, including demographic, geographic,

Medicaid eligibility, and comorbidities are shown below. Table 4.30 shows the sample

characteristics for the HIV-positive group by non-adherence and non-adherence.

TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232)

n % n % n %Subjects 176 75.9% 56 24.1% 232 100%Age groups

18–34 73 41.5% 17 30.4% 90 38.8%35–49 73 41.5% 29 51.8% 102 44.0%50 years or older (reference) 30 17.0% 10 17.9% 40 17.2%

SexMale 54 30.7% 17 30.4% 71 30.6%Female (reference) 122 69.3% 39 69.6% 161 69.4%

Race/EthnicityWhite race non-hispanic 26 14.8% 17 30.4% 43 18.5%Black race non-hispanic 115 65.3% 31 55.4% 146 62.9%Other race or Not Determined, non-Hispanic

10 5.7% 2 3.6% 12 5.2%

Hispanic race and/or ethnicity 25 14.2% 6 10.7% 31 13.4%

TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232)

< 90% MPR > 90%MPR Total

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TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232)

Table 4.31 shows the characteristics for the AIDS-diagnosed subjects. TABLE 4.31: Descriptive statistics for AIDS-diagnosed Medicaid-insured subjects by ART medication possession ratio adherence categories (n=270)

n % n % n %Geographic Areas - High and Low Median Income

Low 64 36.4% 26 46.4% 90 38.8%High 112 63.6% 30 53.6% 142 61.2%

Geographic Areas - Rural and Urban Counties

Rural 15 8.5% 9 16.1% 24 10.3%Urban 161 91.5% 47 83.9% 208 89.7%

Eligibility category SSI 127 72.2% 42 75.0% 169 72.8%TANF (reference) 49 27.8% 14 25.0% 63 27.2%

Discontinuous coverage (up to 3 months ineligibility per year)

27 15.3% 4 7.1%31

13.4%

Mental Illness ComorbiditiesDepression and/or anxiety 41 23.3% 15 26.8% 56 24.1%Alcohol abuse and/or substance abuse

12 6.8% 4 7.1%16 6.9%

Severe mental illness 22 12.5% 7 12.5% 29 12.5%Co-morbidity diagnoses counts

No comorbidities (reference) 58 33.0% 22 39.3% 80 34.5%1 51 29.0% 11 19.6% 62 26.7%2 or more 67 38.1% 23 41.1% 90 38.8%

Continued, TABLE 4.30: Descriptive statistics for HIV-positive Medicaid-insured subjects by ART medication possession ratio adherence categories (n=232)

< 90% MPR > 90%MPR Total

n % n % n %Subjects 219 81.1% 51 18.9% 270 100%Age groups

18–34 59 26.9% 14 27.5% 73 27.0%35–49 129 58.9% 29 56.9% 158 58.5%50 years or older (reference) 31 14.2% 8 15.7% 39 14.4%

TABLE 4.31: Descriptive statistics for AIDS-diagnosed Medicaid-insured subjects by ART medication possession ratio adherence categories (n=270)

< 90% MPR Total> 90%MPR

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n % n % n %Sex

Male 66 30.1% 24 47.1% 90 33.3%Female (reference) 153 69.9% 27 52.9% 180 66.7%

Race/EthnicityWhite race, non-Hispanic (reference)

40 18.3% 18 35.3% 58 21.5%

Black race, non-Hispanic 128 58.4% 22 43.1% 150 55.6%Other race or Not Determined, non-Hispanic

24 11.0% 3 5.9% 27 10.0%

Hispanic race and/or ethnicity 27 12.3% 8 15.7% 35 0.1296Geographic Areas - High and Low Median Income

Low 71 32.4% 24 47.1% 95 35.2%High 148 67.6% 27 52.9% 175 64.8%

Geographic Areas - Rural and Rural 12 5.5% 6 11.8% 18 6.7%Urban 207 94.5% 45 88.2% 252 93.3%

Eligibility category SSI 171 78.1% 39 76.5% 210 77.8%TANF (reference) 48 21.9% 12 23.5% 60 22.2%

Discontinuous coverage (up to 3 months ineligibility per year)

27 12.3% 5 9.8% 32 11.9%

Mental Illness ComorbiditiesDepression and/or anxiety diagnosis

61 27.9% 1325.5% 74 27.4%

Alcohol abuse and/or substance abuse

30 13.7% 59.8% 35 13.0%

Severe mental illness 28 12.8% 7 13.7% 35 13.0%Co-morbidity diagnoses counts

No comorbidities (reference) 42 19.2% 11 21.6% 53 19.6%1 36 16.4% 13 25.5% 49 18.1%2 or more 141 64.4% 27 52.9% 168 62.2%

Continued, TABLE 4.31: Descriptive statistics for AIDS-diagnosed Medicaid-insured subjects by ART medication possession ratio adherence categories (n=270)

< 90% MPR Total> 90%MPR

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Objective 2: Model diagnostics

Objective 2 of this research predicted mean monthly total healthcare expenditures

in the 24 month measurement for subjects in the ART adherence and non-adherence

groups, controlling for demographic, geographic, Medicaid eligibility and clinical factors.

Healthcare expenditures are typically positively skewed with a very long right tail

and non-normally distributed (Manning, Basu, & Mullahy, 2003). The HIV mean

healthcare expenditures in this research were no exception, as the skewness was 3.00, and

the kurtosis was 10.6. The Kolmogorov-Smirnov test of goodness-of-fit confirms the

non-normality (p<0.001).

Figure 4.11: Non-normal distribution of total healthcare expenditure for the HIV-positive group

Figure 4.11 illustrates the non-normal shape of the distribution of the total

healthcare expenditure (Q) for the HIV-positive group. The AIDS-diagnosed group mean

healthcare expenditures distribution also was skewed and non-normal (3.02) and kurtotic

(10.9) The Kolmogorov-Smirnov test of goodness-of-fit confirms the non-normality

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80

(p<0.001). Figure 4.10 shows the distribution more closely follows a gamma distribution

curve. Note extreme variance illustrated in the histogram in Figure 4.10, also true for the

AIDS model. While the unadjusted mean for the HIV-positive mean monthly total

expenditure was $1,439, and the median was only $974. The AIDS model mean was

$2,250, and the median was $1,341. These differences between the mean and the median

indicate the importance of high value outliers in the model distributions.

To account for the skewed distribution and wide variation in expenditures, recent

health economics literature modeling health care expenditures using a generalized linear

model with a gamma distribution and a log link variance function (Clark, Yampolskaya,

& Robst, 2011; Manning et al., 2003; Manning, Basu, Mullahy, & Manning, 2002;

Manning, 2012; Moran, Solomon, Peisach, & Martin, 2007; Mullahy, 1998, 2009;

Nachega et al., 2010; Robst, 2009, 2012). An alternate method of estimation in order to

correct for skewness is through lognormal transformation of the healthcare expenditure

dependent variable (Manning & Mullahy, 2001). Although transforming the expenditures

can cause problems with interpretation and retransformation bias (Manning et al., 2002),

ordinary least squares (OLS) can be modeled with the resultant normally distributed

dependent variable.

Manning and Mullahy (2001) recommend procedures to determine which

approach (GLM versus OLS) is more appropriate. First, the log-scale residuals should be

obtained by estimating the expenditure dependent variable using GLM. In order for a

GLM model to be appropriate, the coefficient of kurtosis of the log-scale residuals should

be less than three. In the cases of the HIV and AIDS models, the log-scale residuals

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coefficient of kurtosis was less than three (1.22 and .29, respectively). Thus, a GLM

model was preferred over OLS.

Figure 4.12 shows that the residua

were slightly heteroscedastic

Although not a focus of this study,

heteroscedasticity would impact the

precision of the coefficients and cause

problems of assessing the relative

importance of various factors in the

model in predicting the expenditure outcome variable

Objective 2: Model results

A regression analysis estimated the expected per patient mean monthly total

healthcare expenditures, as measured on a continuous scale. As discussed above, given

the disparity in mean total he

the AIDS-diagnosed group show

2) AIDS. Both of the models were specified with the same parameters.

Objective 2 multivariate

(GLM) with a log link function and gamma distribution was employed

Mullahy, 2001). The model

ART adherence group and

geographic, clinical, and Medicaid eligibility factors.

total healthcare expenditures (Q) for the

less than those in the ART non

81

of kurtosis was less than three (1.22 and .29, respectively). Thus, a GLM

model was preferred over OLS.

shows that the residuals

slightly heteroscedastic.

Although not a focus of this study,

heteroscedasticity would impact the

precision of the coefficients and cause

problems of assessing the relative

importance of various factors in the

model in predicting the expenditure outcome variable (Moran et al., 2007)

esults

A regression analysis estimated the expected per patient mean monthly total

healthcare expenditures, as measured on a continuous scale. As discussed above, given

the disparity in mean total healthcare expenditures between the HIV-positive group and

diagnosed group shown in Figure 4.8, two models were specified: 1) HIV and

2) AIDS. Both of the models were specified with the same parameters.

ultivariate regression HIV model. A generalized linear model

(GLM) with a log link function and gamma distribution was employed (Manning &

The model predicted the mean monthly total healthcare expenditures for

and non-adherence group, controlling for demographic,

and Medicaid eligibility factors. It was hypothesized that the mean

total healthcare expenditures (Q) for the in the ART adherence group (>90%) would be

se in the ART non-adherence group (<90%).

Figure 4.12: Predicted residuals

of kurtosis was less than three (1.22 and .29, respectively). Thus, a GLM

(Moran et al., 2007).

A regression analysis estimated the expected per patient mean monthly total

healthcare expenditures, as measured on a continuous scale. As discussed above, given

positive group and

.8, two models were specified: 1) HIV and

generalized linear model

(Manning &

the mean monthly total healthcare expenditures for

adherence group, controlling for demographic,

It was hypothesized that the mean

90%) would be

Figure 4.12: Predicted residuals

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82

As shown in Table 4.32 below, the results indicate that, controlling for other

factors, the null hypothesis was not rejected for the HIV-positive group. Interpretation of

the estimate for the non-adherent group was reported as relative to the reference group

and computed as e- 1. The non-adherent group has significantly lower expected total

healthcare expenditures (-40%, p<.001) than the ART adherent group.

TABLE 4.32: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve HIV-positive subjects (n=232)

ART adherence< 90% MPR -0.52 0.11 -0.29 -0.74 <.001 *** -0.40> 90% MPR (reference) - - - - -

Age groups18–34 -0.11 0.15 0.18 -0.41 0.4489 -0.1135–49 -0.02 0.14 0.26 -0.30 0.9015 -0.0250 years or older (reference) - - - - -

SexMale -0.05 0.11 0.17 -0.27 0.6374 -0.05Female (reference) - - - - -

Race/EthnicityWhite race, non-Hispanic (reference)

- - - - -

Black race non-Hispanic 0.11 0.13 0.37 -0.14 0.3845 0.12Other race, or not determined, non-Hispanic

0.15 0.25 0.63 -0.34 0.5554 0.16

Hispanic race and/or ethnicity 0.12 0.18 0.46 -0.23 0.5134 0.12*** < 0.001; ** <0.01; * <0.05

TABLE 4.32: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve HIV-positive subjects (n=232)

Parameter Estimate Std Error95% Confidence

LimitsP

valueeββββ - 1

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83

The mean predicted per person mean monthly expenditures for the non-adherent group

was $1,291 (95% CL $840-$2,004); the mean predicted per person mean monthly

expenditures for the adherent group was $1,926 (95% CL $1,157-$3,231).

High & Low Median Income Counties

Low 0.29 0.10 0.50 0.09 0.0045 ** 0.34High - - - - -

Rural and Urban CountiesRural 0.07 0.16 0.38 -0.25 0.6805 0.07Urban - - - -

Eligibility category SSI 0.14 0.12 0.37 -0.09 0.223 0.15TANF (reference) - - - -

Discontinuous coverage (up to 3 months ineligibility in year)

-0.07 0.10 0.13 -0.27 0.4795 -0.07

Mental Illness ComorbiditiesDepression and/or anxiety diagnosis

0.37 0.12 0.62 0.13 0.0025 ** 0.45

Alcohol abuse and/or substance abuse

0.34 0.21 0.75 -0.07 0.1057 0.41

Severe mental illness 0.10 0.17 0.43 -0.23 0.5373 0.11Other co-morbidity levels (counts)

0 (reference) - - - - -1 0.11 0.12 0.36 -0.13 0.355 0.122 or more 0.85 0.12 1.08 0.62 <.001 *** 1.34

*** < 0.001; ** <0.01; * <0.05

Continued, TABLE 4.32: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve HIV-positive subjects (n=232)

Parameter Estimate Std Error95% Confidence

LimitsP

valueeββββ - 1

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84

Figure 4.13: HIV-positive model adjusted mean total healthcare expenditures (n=232)

Also, the model indicated that those living in low median income counties had

significantly higher expected mean monthly total healthcare expenditures for the

measurement period (34%, p<.01). Also, subjects diagnosed with depression and/or

anxiety had significantly higher expected mean monthly total healthcare expenditures

(45%, p<.01), compared to those without a depression and/or anxiety diagnosis. Finally,

the HIV-positive subjects with 2 or more comorbidities had significantly higher expected

mean total monthly healthcare expenditures for the 24 month measurement period, as

compared to those subjects with no comorbidity diagnoses (134%, p<.001).

Objective 2 multivariate regression AIDS model. As with the HIV-positive

model above, regression analysis for the AIDS-diagnosed group estimated the expected

per patient mean monthly total healthcare expenditures in the 24 month measurement

(n=270). Using GLM with a log link function and gamma distribution, the model

predicted the difference the mean monthly total healthcare expenditures for ART

adherence group and non-adherence group, controlling for relevant factors. It was

$1,291

$1,926

$0

$500

$1,000

$1,500

$2,000

$2,500

Non-adherent(<90%; n=176) Adherent (>90%; n=56)

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85

hypothesized that the mean total healthcare expenditures (Q) for the ART adherence

group would be less than those in the ART non-adherence group.

As shown in Table 4.33 below, the null hypothesis was not rejected. Controlling

for other model factors, there was no significant difference between the expected mean

monthly total healthcare expenditures ART non-adherent group and the ART adherent

group among the AIDS-diagnosed subjects. The mean predicted per person mean

monthly expenditures for the non-adherent group was $2,279 (95% CL $1,572-$3,322);

the mean predicted per person mean monthly expenditures for the adherent group was

$2,005 (95% CL $1,387-$2,913).

TABLE 4.33: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve AIDS-diagnosed subjects (n=270)

ART adherence< 90% MPR -0.12 0.1103 0.10 -0.33 0.29 -0.11> 90% MPR (reference) - - - -

Age groups18–34 -0.18 0.1449 0.10 -0.46 0.22 -0.1635–49 -0.03 0.1252 0.22 -0.28 0.81 -0.0350 years or older (reference) - - - -

SexMale -0.10 0.095 0.08 -0.29 0.27 -0.10Female (reference) - - - -

Race/EthnicityWhite race, non-Hispanic (reference)

- - - -

Black race non-Hispanic -0.06 0.1129 0.16 -0.28 0.57 -0.06Other race, or not determined, non-Hispanic

-0.05 0.1608 0.27 -0.36 0.76 -0.05

Hispanic race and/or ethnicity -0.01 0.1525 0.29 -0.31 0.95 -0.01*** < 0.001; ** <0.01; * <0.05

TABLE 4.33: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve AIDS-diagnosed subjects (n=270)

Parameter Estimate Std Error95% Confidence

LimitsP

valueeββββ - 1

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86

Also shown in Table 4.33 above, those living in low median income counties had

significantly higher expected total healthcare expenditures (37%, p<.01). Additionally,

subjects diagnosed with severe mental illness (SMI) had significantly higher expected

total healthcare expenditures (52%, p<.01). Finally, the AIDS-diagnosed subjects with 2

or more comorbidities had significantly higher expected mean monthly total healthcare

expenditures for the 24 month measurement period, as compared to those subjects with

no comorbidity diagnoses (191%, p<.001).

High & Low Median Income Counties

Low 0.31 0.091 0.49 0.13 0.001 ** 0.37High - - - -

Rural and Urban CountiesRural -0.25 0.1744 0.09 -0.60 0.15 -0.22Urban - - - -

Eligibility category SSI 0.07 0.1192 0.31 -0.16 0.54 0.08TANF (reference) - - -

Discontinuous coverage (up to 3 months ineligibility in year)

0.05 0.0969 0.24 -0.14 0.60 0.05

Mental Illness ComorbiditiesDepression and/or anxiety diagnosis

-0.01 0.0975 0.18 -0.20 0.92 -0.01

Alcohol abuse and/or substance abuse

0.15 0.1316 0.41 -0.11 0.26 0.16

Severe mental illness 0.42 0.128 0.67 0.17 0.001 ** 0.52Other co-morbidity levels (counts)

0 (reference) - - - -1 0.27 0.1396 0.54 -0.01 0.05 0.312 or more 1.07 0.1148 1.29 0.84 <0.001 *** 1.91

*** < 0.001; ** <0.01; * <0.05

Continued, TABLE 4.33: Generalized Linear Model (gamma, log link) for total healthcare costs in 24 month period among Medicaid-insured previously antiretroviral therapy (ART) naïve AIDS-diagnosed subjects (n=270)

Parameter Estimate Std Error95% Confidence

LimitsP

valueeββββ - 1

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87

Chapter Five: Conclusions and Recommendations

Objective 1: Discussion

When antiretroviral medication therapy (ART) is available to PLWHA,

HIV/AIDS becomes a chronic disease. Poor ART adherence predicts increased morbidity

and mortality (Hogg et al., 2002; Lieb et al., 2002), virologic failure (Maggiolo et al.,

2005) and increases HIV transmission risk (Reynolds et al., 2011). Unfortunately, the

results of Objective 1 confirm that most subjects were non-adherent to ART (78.7%), and

that the determinants associated with non-adherence among vulnerable populations were

multifaceted.

Using retrospective Medicaid administrative claims, Objective 1 of this research

examined the factors associated with ART non-adherence among previously 514 non-

pregnant, non-elderly ART naïve Medicaid-insured adults diagnosed with HIV or AIDS.

A closer examination of the PLWHA sample characteristics revealed subjects similar to

Florida Medicaid enrollment as a whole. Females made up over 64% of non-elderly adult

Florida Medicaid enrollment, and under 35 year old adult population was over 50% of the

total (Florida Agency for Health Care Administration, 2013). In this sample, the largely

young and female proportions (one-third under 35 and two-thirds female) represent the

typical Medicaid-eligible population, rather than the older and male-dominated U.S.

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88

population of PLWHA (where 51% were under the age of 44 years and only 24.3% were

female) (Centers for Disease Control and Prevention, 2012).

Furthermore, Florida Medicaid was disproportionately comprised of blacks

(28%), as compared to the general U.S. population (13%) (Florida Agency for Health

Care Administration, 2013; U.S. Census Bureau, 2013a). Also, blacks account for greater

proportion of HIV prevalence in the U.S. (44%) than any other racial category (Centers

for Disease Control and Prevention, 2012). The high proportion of blacks in this sample

(59%) was consistent with the large proportion enrolled in Medicaid and disproportionate

share that have been diagnosed with HIV in the United States. Not surprisingly, a large

majority of subjects live in urban counties (91%). This sample characteristic sets a

context for the subjects of being economic disadvantaged.

Finally, Florida Medicaid eligibility for non-elderly adults have been split roughly

in half among Temporary Assistance for Needy Families (TANF), a program for low-

income families with children, and Supplemental Security Income (SSI), a program for

low-income, disabled persons (Agency for Health Care Administration, 2013a, 2013b;

Florida Agency for Health Care Administration, 2013). In this sample, however, over

76% of the subjects were eligible for Medicaid through the SSI program. This Medicaid

eligibility characteristic indicates that a majority of the subjects were sick enough for

their doctors to certify that they too sick to work (“Social Security for People Living with

HIV/AIDS,” 2005).

As described above, among the 514 subjects in the study, 21.3% were adherent

(>90% MPR) to ART, and the overall mean adherence was 56%. The adherence to ART

in this research was similar to the pooled mean of 55% (95% CI, 0.49-0.62) produced by

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89

Mills et al. (2006) meta-analysis. Another large study of 3,788 Medicaid-insured

subjects, found that 26% of the subjects were 80% adherent to ART, and the overall

adherence mean was 53% (Becker, 2002). Thus, the proportion of adherent subjects and

overall mean adherence percentage among the sample used in this research was similar to

another large Medicaid-insured study cohort.

According to the results of the full and partial logistic regression models, race and

ethnicity were important factors associated with non-adherence to ART. While race and

ethnicity have not been universally found to be related to non-adherence to ART in the

published literature (Mills et al., 2006), among other ART adherence studies examining

Medicaid-insured or low-income subjects, race and ethnicity were significant predictors

of non-adherence (Kong et al., 2012; Lillie-Blanton et al., 2010; Zhang et al., 2013).

Other social factors, including racism, may be at play in low income populations that

render race and ethnicity a significant factor in ART adherence. It may be that

interactions of various stigmas, including Medicaid insurance coverage, racial

discrimination and HIV-status, play in ART non-adherence among low-income

individuals (Bogart, Wagner, Galvan, & Klein, 2010).

Also, this research found a strong relationship between the number of concurrent

of ART medications filled in the first month and non-adherence ART. Although other

ART adherence studies have found association with the number concurrent of ART

medications (Bangsberg et al., 2010; Kleeberger et al., 2001; Lazo et al., 2007; Maggiolo

et al., 2005), others show no relationship to non-adherence (Moore et al., 2011; Singh et

al., 1999). Despite the inconsistent findings in the literature, the number of concurrent

medications appears to be important, especially among vulnerable populations, such as

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90

Medicaid and/or insured low-income populations (Bangsberg et al., 2010). In fact, the

results of this research showed the strength of association increases as the number of

medication increases – from over two times for two medications to almost seven times

the odds in the reduced model, as compared to a single medication fill.

In addition, understanding the role non-HIV chronic disease comorbidities plays

in ART adherence may be able to improve the treatment of PLWHA. The results of

Objective 1 show that those with one or more non-HIV chronic disease diagnosis was

negatively associated with non-adherence to ART, consistent with other studies

(Crawford et al., 2013; Giordano et al., 2007; Webster, 2010). It is possible that chronic

care practices by providers and/or self-management efforts by patients for other chronic

diseases apply to ART adherence practices (Swendeman, Ingram, & Rotheram-Borus,

2009).

On the other hand, the opposite also may true. It may be possible that providers

focus on sicker patients, and consequently, were inattentive to patients without

comorbidities (Crawford et al., 2013). However, results from the present study showed

that the association of a chronic disease diagnosis to ART non-adherence remained

negatively significant even after controlling for measures of outpatient utilization. This

result suggests that the effect may not be associated to volume of care provided, but

rather related to the quality of that care.

Considering the determinants to ART adherence broadly, the interplay of

important unmeasured variables may be related to both non-HIV chronic disease and

ART adherence may be at work. Perhaps absent in the model were variables measuring

barriers to health seeking behaviors. Indeed, the most consistent association to non-

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adherence to ART across published studies have been those factors related to barriers to

health seeking behaviors, such as low patient self-efficacy, life stress, and lack of social

support (Ammassari et al., 2002), which were mot measured in the present study.

Furthermore, the significance of adherence to antidepressant medications variable

in the full and reduce models underscores the importance of possible unmeasured

psychosocial variables. Specifically, the results showed that among those with an anxiety

and/or depression diagnosis, adherence to antidepressant medications was positively

related to ART adherence. It may be that the same behavioral factors that are associated

with adherence to antidepressants are related with adherence to ART.

In addition to unmeasured factors, the negative association of non-HIV chronic

diseases to ART non-adherence may be confounded with adverse drug reactions (ADR).

The inclusion of an ADR count variable in the model mediated the significance of the

chronic disease variable’s significant negative association to non-adherence. There are a

few relationships between covariates that should be considered. Most directly, ART

adherence may lead to ADR diagnoses. For example, this research found significantly

higher dyslipidemia (an abnormal level of lipids in the blood) in the ART adherent

subjects, as compared to the non-adherent group (p<0.001). It can be reasonably

concluded that dyslipidemia is an effect of increased ART (as opposed to the

dyslipidemia increasing ART adherence). However, no differences between adherence

groups were found for other ADR diagnoses, such as nausea and dizziness. One could

conclude that nausea could be both a consequence of ART adherence and a cause of ART

non-adherence (Capili & Anastasi, 1998).

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Next, diagnoses classified as ADR in this research, such as nausea, dizziness,

abnormal glucose and dyslipidemia, may be associated with chronic diseases

independently of HIV-infection and ART. Strong association of dyslipidemia is seen in

heart disease (Lehto et al., 1997), chronic kidney disease (Tsimihodimos, Mitrogianni, &

Elisaf, 2011) and diabetes (Goldberg, 2001). Also, abnormal glucose has been found to

be highly prevalent in coronary heart diseases (Bartnik et al., 2004).

Lastly, the interplay of the three factors (ADR, ART adherence, and chronic

disease) is further complicated by the influence of HIV-infection on chronic disease. For

example, some cardiovascular complications, such as cardiomyopathy and pericarditis,

are associated with HIV infection (Sudano et al., 2006). Also, the impact of HIV-

infection of osteoporosis was seen in HIV-positive subjects prior to the introduction of

ART, although later found to be exasperated by protease inhibitor-based ART

(Montessori, Press, Harris, Akagi, & Montaner, 2004).

In the full model, the type of ART-regimen (PI, NNRTI, etc.) was found not to

predict non-adherence to ART, consistent with other studies in literature (Ammassari et

al., 2002). Although NNRTI resulted in significantly higher odds of non-adherence, as

compared to PI regimens, in a version of the models, the statistical association did not

exist when the number of concurrent ART medications was included in the model.

Unexpectedly, mental illness comorbidities, such as depression and/or anxiety,

severe mental illness, and alcohol abuse and/or substance abuse were not significant

predictors of ART non-adherence in the full model. These results were surprising, since

many studies these show strong associations of mental illness comorbidities to ART non-

adherence among many different populations and settings (Hendershot et al., 2009; Hicks

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93

et al., 2007; Himelhoch et al., 2009; Horberg et al., 2008; Kleeberger et al., 2001; Mellins

et al., 2009; Tegger et al., 2008).

Also unexpected was the non-significance of the AIDS-diagnosis compared to the

HIV-positive group in predicting ART non-adherence. According to Nieuwkerk et al.

(2000), ART may benefit symptomatic individuals with HIV or AIDS, but ART may

have a negative impact on asymptomatic HIV-positive subjects due to side effects and

other burdens. Future research may be able to discriminate between asymptomatic HIV

and symptomatic HIV subjects in order to illuminate any association of HIV infection

disease severity with non-adherence to ART.

Objective 1: Recommendations

Based on the results of Objective 1, three policies are recommended. First, race

and ethnicity factors were important factors associated with non-adherence in the present

study and other published results on Medicaid-insured PLWHA (Kong et al., 2012;

Lillie-Blanton et al., 2010; Zhang et al., 2013). Identification of these disparities has led

to research uncovering the barriers to ART adherence for non-white PLWHA, such as co-

occurring stigmas associated with low-income, race, and HIV infection (Bogart et al.,

2010). Also, extensive ART adherence interventions guidelines have been promulgated

based on a total of 325 randomized control trials and pilot studies (Thompson et al.,

2012). Therefore, researchers should focus on the translation of evidence on racial/ethnic

disparities, cultural and behavioral barriers, and effective interventions to enable

healthcare providers to improve ART adherence Medicaid-insured PLWHA. Translation

and dissemination of these lines of research into practice is particularly salient from a

policy perspective, as the Section 5307 of the Affordable Care Act authorized cultural

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94

competency training for healthcare providers, but such Health Professions Education

grants have yet to receive funding (National Association of County & City Health

Officials, 2013).

Next, in light of the association of comorbid chronic conditions with ART

adherence, state policymakers should continue to support HIV chronic disease

management. In Florida, statewide Medicaid disease management programs have been

effective in reducing avoidable healthcare utilization and expenditures for patients with

chronic illness (Mitchell & Anderson, 2000) and improve survival among PLWHA

(Anderson & Mitchell, 2004). However, in the past, these programs have been conducted

separately through the fee-for-service Medicaid program. The recent change to

mandatory Medicaid managed care places the statewide AIDS disease management

program in jeopardy. State Medicaid programs should continue the effective policy of

contracting with competent disease management vendors that recognize the interplay of

comorbid chronic conditions with HIV care management and ART adherence.

Finally, the relationship of the number of concurrent ART medications in a

regimen to ART adherence, suggests that policies related to regimen simplification would

be prudent (Nachega et al., 2011). State Medicaid programs and managed care

organizations often employ preferred drug lists (PDL) to control costs and ensure access

(Ovsag, Hydery, & Mousa, 2008). Also, there are certain pharmaceutical “prior approval”

strategies that are employed to change physician prescribing behaviors. For example, step

therapy programs require certain drugs to be tried before other (usually more expensive)

prescription medications are allowed to be filled at the pharmacy. This principle can be

applied to changing physician prescribing patterns with the focus on increasing

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95

medication adherence, rather than cost control (Parks & Surles, 2004). All PDL and prior

approval policies should be conducted with Pharmacy and Therapeutics Committee and

physician oversight. Policies to simplify first-line regimens utilizing specialized ART

PDLs and prior approval processes could be implemented to improve ART adherence.

Objective 1: Future research

Substantial synthesis of ART adherence and the translation to effective

interventions has been offered by previous research (Simoni, Amico, Smith, & Nelson,

2010). Missing, however, are comparative effectiveness research (CER) regarding ART

adherence among the Medicaid-insured. Among the 62 medication adherence CER

studies found in a recent literature review by Simoni, et al. (2010), only one looked at

PLWHA (in combination with depression), and none examined the Medicaid-insured

population specifically. Especially considering the increased funding for CER offered by

ACA, researchers should focus efforts on understanding the comparable effectiveness of

interventions for improving ART adherence among the Medicaid-insured.

Also, through the development of this research, data revealed that 130 subjects

diagnosed with AIDS did not initiate ART within the multiyear period of claims. This

alarming development warrants further investigation. These individuals were AIDS-

diagnosed, had adequate eligibility and enrollment, obtained other healthcare services,

but did not fill ART pharmaceutical claims. It is important to learn what factors were

associated with ART initiation among Medicaid-insured AIDS diagnosed subjects.

Objective 1: Limitations

Although Objective 1 was carefully planned and conducted, certain limitations

exist that may affect the results and interpretation. First, the restrictive inclusion and

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96

exclusion criteria caused the sample to be small, although statistically valid. The reasons

for the small sample were threefold. First, a large portion of HIV-positive individuals in

the Agency for Health Care Administration (AHCA) administrative files were dually

eligible for Medicare and Medicaid. In these instances, Medicare would pay the majority

of the claims, and, therefore, these subjects were excluded from the sample. Next, the

requirement of 12 months of Medicaid enrollment with no ART claims excluded a

substantial portion of subjects. By limiting the sample to antiretroviral treatment naïve

subjects, comparisons could be made to the other studies with similar sampling strategies

(Acurcio et al., 2006; Bozzette et al., 2001; Gardner et al., 2008; Nachega et al., 2010).

Third, this research aimed to extend the measurement period as long as possible without

sacrificing overall sample size. Twenty-four months, while still short-term in relation to a

lifelong chronic disease, balanced treatment duration with adequate sample size

considerations.

While using pharmacy claims data has been found to be valid proxy for

medication consumption (Steiner & Prochazka, 1997), three issues relating to

measurement of ART adherence using MPR should be considered. First, discontinuous

eligibility was measured as though the subject was without ART during the lapse period.

Discontinuous eligibility was not found not be a significant predictor of non-adherence to

ART in the present study. Next, researchers acknowledge that measurement of ART

adherence relies heavily on the assumption that filling prescriptions is strongly correlated

with the patients actually taking the medicines (Reynolds, 2004). Finally, consensus

among researchers has not been formed regarding the best cut-off for ART adherence as a

dichotomous measure (Mills et al., 2006). Among the Medicaid-insured PLWHA

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subjects in this study, the 90% MPR cut-off aimed to balance clinical validity and sample

size considerations.

Also, the exclusive use of administrative data presents certain limitations for this

research. First, the retrospective design of this study means that no causal conclusions

about the relationship of the factors to ART adherence can be made. Also, physician

prescribing information remains unknown. More specifically, there may be instances

when prescriptions were written and not filled by the patient. Alternatively, the absence

of ART medication refills could actually be strategic treatment interruption ordered by

the physician, not true ART non-adherence. Also, administrative data presents challenges

impacting the thoroughness of the present research. Certain variables were not

represented in the claims, such as provider types, Project AIDS Care enrollment, and

cognitive behavioral therapy procedure codes. Furthermore, data restrictions applied by

the Florida Agency for Health Care Administration for privacy protection reasons

prevented use of zip codes in the measurement of factors related to geography.

Finally, the exclusive use of claims data precludes the ability to measure

important psychosocial issues related to ART adherence, such as subjects’ inclination

toward health seeking behaviors. Stronger conclusions regarding the association of

race/ethnicity and regimen-related factors could have been made if supplemented by

information relating perception of provider engagement, stigma, patient self-efficacy, and

available social support.

Objective 1: Conclusion

Although these limitations exist, Objective 1 demonstrated that a large majority of

Medicaid-insured PLWHA were non-adherent to ART. Also, the logistic modeling

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provides evidence of the significant relationship between ART adherence and

race/ethnicity, multiple concurrent ART medication regimens, chronic disease diagnoses,

and antidepressant adherence. These were important contributions to the understanding of

ART adherence among vulnerable populations.

Objective 2: Discussion

Uncertainty abounds regarding the association of ART adherence to total

healthcare expenditures. The results of Objective 2 of this research were mixed regarding

association of ART adherence with reduced total healthcare expenditures among

previously ART naïve Medicaid-insured PLWHA in a 24 month period. Non-adherent

HIV-positive subjects had significantly lower costs, but expenditures for non-adherent

AIDS-diagnosed subjects were not statistically different than those ART adherent

subjects.

Two similar studies to this research found that ART adherence was independently

related to a reduction in healthcare expenditures (Bozzette et al., 2001; Nachega et al.,

2010), while two others showed that improved adherence to ART was associated with an

increase in total expenditures (Acurcio et al., 2006; Gardner et al., 2008). Inconsistent

results such as these fuel the broader debate of whether adherence to recommended care

for chronic diseases is associated with decreased expenditures. In the short-term,

adherence to medications for certain chronic diseases is significantly related to increased

future costs – as reported by Robinson et al. (2006) for antidepressant medications and by

Mattke et al. (2010) for asthma medications. More often than not, though, published

research indicates decreased total healthcare costs associated with medication adherence.

This is true in research by Esposito (2009) on congestive heart failure patients, Roebuck

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et al. (2011) for a variety of conditions, such as certain vascular conditions, congestive

heart failure, hypertension, diabetes, and dyslipidemia, and Sokol et al. (2005) results on

diabetes, hypertension, and high cholesterol and medication adherence.

The results of the descriptive statistics for AIDS-diagnosed subjects illustrated in

Figure 4.9 showed that unadjusted mean ART-related expenses for those subjects

adherent to ART were $267 less than the increased inpatient expenses associated with

being ART non-adherent. This suggested a beneficial trade-off between ART costs and

inpatient costs. However, in the multivariate model with AIDS-diagnosed patients, the

increased expenditures from ART may not be fully recovered by decreases in inpatient

costs, controlling for other factors. Considering all factors, the predicted $274 mean

savings for ART adherent group, compared to the non-adherent group, is not statistically

significant. The reason for this is likely due to the variability in total healthcare

expenditures associated with AIDS diagnosis

However, for HIV-diagnosed subjects not yet diagnosed with AIDS with an

increase in ART expenditures, the concomitant reduction in inpatient costs did not

materialize. The unadjusted mean ART expenditures were almost twice as high for the

adherent group ($761) as the non-adherent group ($413). The unadjusted mean inpatient

expenditures for the adherent group was $309, and the non-adherent groups was only

$322. Unfortunately, the cost saving benefit of ART may emerge once a HIV-positive

individual becomes sick enough to be diagnosed with AIDS.

Furthermore, the expected total healthcare expenditures for the PLWHA subjects

reveal an incentive problem for managed care organizations (MCOs) operating in the

under the Medicaid managed care program. In the Florida Medicaid managed care

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program, AHCA pays the organizations a separate per member per month capitation

payment for the HIV and AIDS categories. For example, the 2010 monthly capitation

payment for an enrollee into a health plan from Jacksonville, Florida diagnosed with HIV

would be approximately $1,634 per month and approximately $2,398 per month for an

enrollee diagnosed with AIDS (Agency for Health Care Administration, 2010). The

managed care plans are responsible for all of the healthcare costs for their members. The

statewide expected mean monthly expenditures for HIV-positive individuals adherent to

ART was $1,926 - more than the capitation rate. However, expected mean monthly

expenditures for the ART non-adherent HIV-positive individuals was $1,291 – less than

the capitation rate. The expected mean monthly expenditures for AIDS-diagnosed

individuals were below the capitation rate for both ART adherent and non-adherent

groups ($2,005 and $2,279, respectively).

While likely an unintended policy consequence, under this payment scenario, a

profit seeking managed care organization would have the incentive to 1) discourage

potentially unprofitable Medicaid recipients diagnosed with HIV from enrolling or

remaining enrolled in their health plan, or 2) fail to invest in the care management

services for potentially appropriate ART adherence for the HIV diagnosed members until

their disease progresses to AIDS where the capitation rate would be sufficient to cover

the cost of care. Considering the evolution of treatment guidelines to recommend earlier

ART initiation (Dieffenbach & Fauci, 2011), the current financing approach for non-

AIDS HIV-positive managed care enrollees may be insufficient.

Finally, the pricing of pharmaceuticals is important to inferences regarding the

impact of ART adherence on healthcare expenditures. In fact, ART medication prices

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greatly influenced the results of other studies examining ART adherence association to

total healthcare expenditures. For example, in Gardner et al. (2008), the authors found an

increase in overall costs when the ART was priced at the average wholesale price (61%

of total expenditures). However, when changing the ART price calculation from actual

proportion of total expenditures (61% of total expenditures) to generic medications prices

(3% of total expenditures), the relationship flipped – increased ART adherence was

associated lower total costs. Also, the decreased total expenditures associated with

increased ART adherence found in the Nachega et al. (2010) South African study may

have been due to the fact that ART was priced at only 13% of total costs. According to

the authors, the much lower prices were negotiated through international pharmaceutical

access programs that are unavailable to U.S. purchasers.

As described in the methodology section above, the ART pharmaceuticals for this

research were priced at the claim dollar amount minus a statutorily mandated 29.1%

rebate for drugs on the Florida Medicaid Preferred Drug List (Florida Statute, 2008). It is

important to note that federally qualified entities in the 340B program may purchase

pharmaceuticals at even greater discounts (Public Health Service Act, 1992). Laws

prohibit duplicate discounts from both Medicaid rebates and 340B pricing. When

Gardner et al. (2008) modeled the ART costs at 340b pricing levels (38% lower than the

average wholesale prices), the researchers found that increased ART adherence was still

associated with increased total costs. In the present research, the additional 8.9% discount

for 340B pricing would not have changed the results.

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Objective 2: Recommendations

In early 2011, Florida Governor Rick Scott signed into law a requirement that all

Medicaid-eligible patients enrolls into managed care organizations (MCOs) (Florida

Statutes, 2011). This policy change was driven by a promise of cost savings to the State

of Florida projected by the MCO industry (Hatter, 2013). However, the law was passed,

in part at least, because MCOs boast about their ability to deliver improved care

(America’s Health Insurance Plans, 2008; Hatter, 2013).

Recognizing the need to encourage improved quality of care among MCOs, the

Florida Medicaid agency (AHCA) requires MCOs to report quality of care measures,

including HIV-related measures such as the ratio of patients diagnosed with AIDS

prescribed ART (Agency for Health Care Administration, 2009). This approach is similar

to the set of quality measures used by 90% of the managed care industry, the Healthcare

Effectiveness Data Information Set (HEDIS) (NCQA, 2009). Such process-based

measures have been shown to be statistically related to health status and quality of life

outcomes (Bradley et al., 2006; Kahn et al., 2007).

There is evidence that MCOs can impact quality of care through certain care

management activities, such as medication adherence, cancer screening, and diabetes care

(Baker & Hopkins, 2010). These efforts are implemented separately from, but in

coordination with, direct healthcare providers. However, MCOs may not perform care

management as expected. As an example, for patients diagnosed with HIV or AIDS,

research on Medicaid managed care versus Medicaid fee-for-service shows little

difference in levels of ART use, hospitalization, or mortality, after adjusting for severity

(Zingmond, Ettner, & Cunningham, 2007).

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The reasons for this lack of performance may be two fold, at least. First, as seen

in the results of Objective 2 of this research, certain quality of care measures have been

shown to be statistically related to increased near-term future total healthcare costs. Next,

even though care management efforts may produce a return on their investment in the

long-term, high membership turn-over (Short et al., 2003) may negate the cost savings

related care management activities in the near-term (Ofman et al., 2004). Due to the

uncertain return on investment in the near-term and membership instability, simply

requiring MCOs to report quality measures to the public may not be enough to induce

MCOs to invest in care management activities that will benefit the long-term health of

members.

In order to reverse the incentives to ration some recommended care, such as

expensive pharmaceuticals, in favor of unlikely, but costly and undesirable services, such

as inpatient, and emergency room visits, incentive bonuses for performance on adherence

to ART should be implemented. Such incentive-based contracts would be intended to

stimulate MCOs to improve quality so they can achieve higher payments (Benjamin &

Garza, 2009). Many payors use incentive-based contracts to retrospectively reward

MCOs based on quality of care process measures in the form of bonuses, fines or tiered

payments (Maio, Goldfarb, Carter, & Nash, 2003). Based on the results of this study, an

incentive bonus would be most strongly recommended for the HIV-positive group that

has initiated ART.

Finally, AHCA currently pays MCOs two separate risk-adjusted capitation

payments for the HIV and AIDS diagnoses. The current HIV/AIDS risk adjustment

payment presents an unfortunate incentive problem. Perversely, under the current

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payment scheme, if a member’s illness intensifies, a MCO’s risk-adjusted payment would

increase. Since the capitation rate for AIDS-diagnosed patients is so much higher and

potentially more profitable, a MCO would have a disincentive to invest in drug adherence

programs that ensure that members diagnosed with HIV do not progress to AIDS

diagnosis. In effect, this penalizes the MCOs that prevent disease and rewards those that

fail to invest in the health of their enrollees.

To mitigate these problems, it is recommended that payors, such as Medicaid,

create risk adjustment payments made to MCOs based on more detailed HIV comorbidity

diagnoses. The more accurately a comorbidity-based risk adjustment payment model

predicts the future healthcare costs of a member, the less incentive the MCO has to

positively or negatively select enrollees. HIV/AIDS is an ideal disease state for which to

develop a risk-adjusted payment methodology because HIV/AIDS is disease for which

risk selection occurs (Glazer & McGuire, 2000) and high cost and high variability exist

(Hill & Gebo, 2007).

Objective 2: Future research

This research demonstrates that multiple comorbidity diagnoses were positively

associated with total healthcare expenditures. Future research aimed at developing an

improved HIV/AIDS risk adjustment payment system that prevents risk selection and

promotes quality of care. Since HIV/AIDS has become a chronic disease with the advent

of effective ART and PLWHA are developing comorbidities associated with aging at a

rate even higher than in the general population (Crawford et al., 2013; Giordano et al.,

2007; Webster, 2010). Any newly developed HIV/AIDS risk-adjustment model should

recognize these comorbidity factors. Diagnosis based risk-adjustment models have been

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developed for Medicaid enrollees (Ettner, Frank, McGuire, & Hermann, 2001; Kronick,

Gilmer, Dreyfus, & Lee, 2000; Robst, 2009) and for HIV/AIDS (Fakhraei, Kaelin, &

Conviser, 2001) and could provide the basis for future risk-adjusted payment systems.

Also, this research measured the ART adherence and total healthcare expenditures

in the near-term – only 24 months. Future research should examine the medium and long-

term association of ART adherence on total healthcare expenditures. This potential

research is particularly salient for two reasons. First, because HIV/AIDS has become a

chronic disease, and as the prevalence increases, the long-term financial impact to our

health system becomes more important to understand. Second, the effectiveness of ART

does not come without problems. It is important to understand how the costs change over

time, considering issues such as ART resistance and ART-related ADR.

Objective 2: Limitations

Objective 2 has certain limitations that may impact the results and conclusions

regarding the relationship of ART adherence to healthcare expenditures. First, this study

exclusively examined secondary data which are often subject to inaccuracies related to

coding, especially for claims payment values. Given the relative small samples included

in the models, possible mistakenly coded large claims values could have impacted the

conclusions. Nevertheless, these kinds of data remain the best source of information on

healthcare utilization for the Medicaid population.

Also, for subjects with discontinuous Medicaid coverage of 3 months or less in a

year, the lapses in coverage lowers ART MPR. While subjects can be reasonably

assumed to be non-adherent to ART in interrupted eligibility months without Medicaid,

there is no way to know whether the subjects accessed ART or other services. Studies

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have shown that when patients return to Medicaid there may be slightly increased

expenditures for the immediate period following the lapse (Hall et al., 2008; Harman et

al., 2007). Thus, it is unknown the exact impact that the discontinuous enrollment has on

overall expenditures. The Objective 2 models showed that the discontinuous eligibility

was not a significant predictor of total healthcare expenditures for the HIV-positive and

AIDS-diagnosed subjects.

Finally, it is important to note that this is not cost-benefit study, but rather an

examination of the direct healthcare costs from the perspective of Medicaid. Certainly,

there is benefit of ART adherence to the patient and to society. Previous literature

provides overwhelming support for ART adherence by decreasing HIV transmission risk

(Reynolds et al., 2011), improving mortality (Lieb et al., 2002) and increasing quality of

life (Hogg et al., 2002). Nonetheless, the focus of this research was on direct healthcare

expenditures for the health insurer.

Objective 2: Conclusion

Although these limitations exist, Objective 2 underscores the challenges with

financial incentives pervasive in the U.S. healthcare system. Much of patient care is

controlled by organizations, such as Medicare Accountable Care Organizations or

Medicaid managed care organizations, which promote their ability to decrease healthcare

costs by improving care management practices. Unfortunately, while medication

adherence for many chronic diseases is cost-saving in the near-term, others may not be.

In circumstances where the financial benefit is ambiguous or only realized in the long-

term, organizations may have the financial incentive to shirk care management

responsibilities or avoid unprofitable patients. Therefore, as policymakers consider

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transferring the financial risk to organizations for patient care, perverse payment

incentives should be fully understood, and efforts should be made to assure quality for

vulnerable populations.

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Appendices

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Appendix A: HIV/AIDS Pharmaceutical National Drug Codes

TABLE A1: HIV/AIDS Pharmaceutical National Drug Cod es

NDC Code Drug Name Drug Generic Name HIC3 Class

00003362212 REYATAZ 300 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

00003362312 REYATAZ 100 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

00003362412 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

00003363112 REYATAZ 200 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

00004024451 INVIRASE 500 MG TABLET

SAQUINAVIR MESYLATE

W5C PI

00004024515 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

00004024648 FORTOVASE 200 MG SOFTGEL CAP

SAQUINAVIR W5C PI

00006057062 CRIXIVAN 100 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057142 CRIXIVAN 200 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057143 CRIXIVAN 200 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057301 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057318 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057340 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057342 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057354 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057362 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00006057465 CRIXIVAN 333 MG CAPSULE

INDINAVIR SULFATE

W5C PI

00074194063 NORVIR 80 MG/ML SOLUTION

RITONAVIR W5C PI

00074663322 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

00074663330 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

00074949202 NORVIR 100 MG RITONAVIR W5C PI

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CAPSULE 00074949254 NORVIR 100 MG

CAPSULE RITONAVIR W5C PI

00173067200 AGENERASE 150 MG CAPSULE

AMPRENAVIR/VITAMIN E

W5C PI

00173067900 AGENERASE 50 MG CAPSULE

AMPRENAVIR/VITAMIN E

W5C PI

00173068700 AGENERASE 15 MG/ML ORAL SOLN

AMPRENAVIR/VITAMIN E/PROP GLY

W5C PI

00173072100 LEXIVA 700 MG TABLET

FOSAMPRENAVIR CALCIUM

W5C PI

00173072700 LEXIVA 50 MG/ML SUSPENSION

FOSAMPRENAVIR CALCIUM

W5C PI

16590006418 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

16590006430 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

16590006460 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

16590006490 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

35356006706 LEXIVA 700 MG TABLET

FOSAMPRENAVIR CALCIUM

W5C PI

35356006760 LEXIVA 700 MG TABLET

FOSAMPRENAVIR CALCIUM

W5C PI

35356006806 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

35356006860 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

35356011406 REYATAZ 300 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

35356011430 REYATAZ 300 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

35356011701 VIRACEPT 625 MG TABLET

NELFINAVIR MESYLATE

W5C PI

35356013830 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

35356013918 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

35356013960 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

35356020760 REYATAZ 200 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

49999043103 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

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130

52959028930 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

52959050712 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

52959050718 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

52959050724 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

52959050730 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

54569424200 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54569424201 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54569424202 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54569424203 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54569433500 NORVIR 100 MG CAPSULE

RITONAVIR W5C PI

54569454300 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454301 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454302 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454303 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454304 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454305 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569454306 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54569456300 FORTOVASE 200 MG SOFTGEL CAP

SAQUINAVIR W5C PI

54569456301 FORTOVASE 200 MG SOFTGEL CAP

SAQUINAVIR W5C PI

54569461300 NORVIR 80 MG/ML SOLUTION

RITONAVIR W5C PI

54569479200 NORVIR 100 MG CAPSULE

RITONAVIR W5C PI

54569481300 AGENERASE 150 MG CAPSULE

AMPRENAVIR/VITAMIN E

W5C PI

54569553000 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

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131

54569553200 REYATAZ 200 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

54569555000 LEXIVA 700 MG TABLET

FOSAMPRENAVIR CALCIUM

W5C PI

54569565600 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

54569566400 INVIRASE 500 MG TABLET

SAQUINAVIR MESYLATE

W5C PI

54569862000 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

54569862001 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

54868369900 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54868369901 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54868369902 INVIRASE 200 MG CAPSULE

SAQUINAVIR MESYLATE

W5C PI

54868378200 NORVIR 100 MG CAPSULE

RITONAVIR W5C PI

54868378201 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

54868378202 NORVIR 100 MG CAPSULE

RITONAVIR W5C PI

54868378203 NORVIR 100 MG SOFTGEL CAP

RITONAVIR W5C PI

54868394700 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54868411000 FORTOVASE 200 MG SOFTGEL CAP

SAQUINAVIR W5C PI

54868411300 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

54868485400 REYATAZ 200 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

54868485700 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

54868495400 LEXIVA 700 MG TABLET

FOSAMPRENAVIR CALCIUM

W5C PI

54868506100 VIRACEPT 625 MG TABLET

NELFINAVIR MESYLATE

W5C PI

54868583800 REYATAZ 300 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

55175520807 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

55175520901 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

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132

55289047727 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

55887023030 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

55887023060 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

55887023090 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

58016069900 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

58016069930 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

58016069960 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

58016069990 CRIXIVAN 400 MG CAPSULE

INDINAVIR SULFATE

W5C PI

60760001018 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

60760001063 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

63010001027 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

63010001030 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

63010001190 VIRACEPT POWDER NELFINAVIR MESYLATE

W5C PI

63010002770 VIRACEPT 625 MG TABLET

NELFINAVIR MESYLATE

W5C PI

68030728401 VIRACEPT 250 MG TABLET

NELFINAVIR MESYLATE

W5C PI

68258914201 REYATAZ 150 MG CAPSULE

ATAZANAVIR SULFATE

W5C PI

35356007306 VIREAD 300 MG TABLET

TENOFOVIR DISOPROXIL FUMARATE

W5I NRTI

35356007330 VIREAD 300 MG TABLET

TENOFOVIR DISOPROXIL FUMARATE

W5I NRTI

54569533400 VIREAD 300 MG TABLET

TENOFOVIR DISOPROXIL FUMARATE

W5I NRTI

54868466900 VIREAD 300 MG TABLET

TENOFOVIR DISOPROXIL FUMARATE

W5I NRTI

61958040101 VIREAD 300 MG TABLET

TENOFOVIR DISOPROXIL

W5I NRTI

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133

FUMARATE 68258900301 VIREAD 300 MG

TABLET TENOFOVIR DISOPROXIL FUMARATE

W5I NRTI

00003196401 ZERIT 15 MG CAPSULE STAVUDINE W5J NRTI 00003196501 ZERIT 20 MG CAPSULE STAVUDINE W5J NRTI 00003196601 ZERIT 30 MG CAPSULE STAVUDINE W5J NRTI 00003196701 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 00003196801 ZERIT 1 MG/ML

SOLUTION STAVUDINE W5J NRTI

00004022001 HIVID 0.375 MG TABLET

ZALCITABINE W5J NRTI

00004022101 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

00054005221 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

00081010793 RETROVIR IV INFUSION VIAL

ZIDOVUDINE W5J NRTI

00081010855 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

00081010856 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

00081011318 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

00087661443 VIDEX 100 MG PACKET DIDANOSINE/SODIUM CITRATE

W5J NRTI

00087661543 VIDEX 167 MG PACKET DIDANOSINE/SODIUM CITRATE

W5J NRTI

00087661643 VIDEX 250 MG PACKET DIDANOSINE/SODIUM CITRATE

W5J NRTI

00087663241 VIDEX 2 GM PEDIATRIC SOLN

DIDANOSINE W5J NRTI

00087663341 VIDEX 4 GM PEDIATRIC SOLN

DIDANOSINE W5J NRTI

00087665001 VIDEX 25 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

00087665101 VIDEX 50 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

00087665201 VIDEX 100 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

00087665301 VIDEX 150 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

00087666515 VIDEX 200 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

00087667117 VIDEX EC 125 MG CAP DIDANOSINE W5J NRTI

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134

SA 00087667217 VIDEX EC 200 MG CAP

SA DIDANOSINE W5J NRTI

00087667317 VIDEX EC 250 MG CAP SA

DIDANOSINE W5J NRTI

00087667417 VIDEX EC 400 MG CAP SA

DIDANOSINE W5J NRTI

00093553006 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

00173010793 RETROVIR IV INFUSION VIAL

ZIDOVUDINE W5J NRTI

00173010855 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

00173010856 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

00173011318 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

00173047001 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 00173047100 EPIVIR 10 MG/ML ORAL

SOLN LAMIVUDINE W5J NRTI

00173050100 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

00173066100 ZIAGEN 300 MG TABLET

ABACAVIR SULFATE

W5J NRTI

00173066101 ZIAGEN 300 MG TABLET

ABACAVIR SULFATE

W5J NRTI

00173066400 ZIAGEN 20 MG/ML SOLUTION

ABACAVIR SULFATE

W5J NRTI

00173071400 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 00378504091 STAVUDINE 15 MG

CAPSULE STAVUDINE W5J NRTI

00378504191 STAVUDINE 20 MG CAPSULE

STAVUDINE W5J NRTI

00378504291 STAVUDINE 30 MG CAPSULE

STAVUDINE W5J NRTI

00378504391 STAVUDINE 40 MG CAPSULE

STAVUDINE W5J NRTI

00555058801 DIDANOSINE 200 MG DR CAPSULE

DIDANOSINE W5J NRTI

00555058901 DIDANOSINE 250 MG DR CAPSULE

DIDANOSINE W5J NRTI

00555059001 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

31722050960 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

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135

31722051560 STAVUDINE 15 MG CAPSULE

STAVUDINE W5J NRTI

31722051660 STAVUDINE 20 MG CAPSULE

STAVUDINE W5J NRTI

31722051760 STAVUDINE 30 MG CAPSULE

STAVUDINE W5J NRTI

31722051860 STAVUDINE 40 MG CAPSULE

STAVUDINE W5J NRTI

35356006530 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 35356006624 EPIVIR 10 MG/ML ORAL

SOLN LAMIVUDINE W5J NRTI

35356007460 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 35356007506 ZIAGEN 300 MG

TABLET ABACAVIR SULFATE

W5J NRTI

35356007560 ZIAGEN 300 MG TABLET

ABACAVIR SULFATE

W5J NRTI

35356018630 VIDEX EC 400 MG CAP SA

DIDANOSINE W5J NRTI

35356020530 EMTRIVA 200 MG CAPSULE

EMTRICITABINE W5J NRTI

35356025930 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

35356028560 ZERIT 30 MG CAPSULE STAVUDINE W5J NRTI 49999011906 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 49999011960 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 49999038618 RETROVIR 100 MG

CAPSULE ZIDOVUDINE W5J NRTI

50962045010 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

50962045205 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

52959038706 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

52959050802 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050804 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050806 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050808 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050814 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050815 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050860 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 52959050906 RETROVIR 100 MG

CAPSULE ZIDOVUDINE W5J NRTI

52959050912 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

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52959050918 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

52959050920 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

52959050924 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

52959050928 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

52959050930 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177200 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177201 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177202 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177203 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177204 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569177205 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54569365700 VIDEX 100 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

54569387700 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

54569387701 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

54569405300 ZERIT 30 MG CAPSULE STAVUDINE W5J NRTI 54569405400 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 54569405401 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 54569422100 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 54569422101 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 54569422102 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 54569431300 VIDEX 100 MG TABLET

CHEWABLE DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

54569431301 VIDEX 100 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

54569433300 EPIVIR 10 MG/ML ORAL SOLN

LAMIVUDINE W5J NRTI

54569433400 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

54569448500 HIVID 0.375 MG TABLET

ZALCITABINE W5J NRTI

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54569451400 VIDEX 4 GM PEDIATRIC SOLN

DIDANOSINE W5J NRTI

54569453800 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

54569488300 ZIAGEN 300 MG TABLET

ABACAVIR SULFATE

W5J NRTI

54569490500 VIDEX 200 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

54569517600 VIDEX EC 400 MG CAP SA

DIDANOSINE W5J NRTI

54569538700 ZERIT 1 MG/ML SOLUTION

STAVUDINE W5J NRTI

54569539000 ZIAGEN 20 MG/ML SOLUTION

ABACAVIR SULFATE

W5J NRTI

54569541200 ZERIT 15 MG CAPSULE STAVUDINE W5J NRTI 54569548000 ZERIT 20 MG CAPSULE STAVUDINE W5J NRTI 54569550100 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 54569550400 VIDEX EC 250 MG CAP

SA DIDANOSINE W5J NRTI

54569552100 EMTRIVA 200 MG CAPSULE

EMTRICITABINE W5J NRTI

54569564200 DIDANOSINE 250 MG DR CAPSULE

DIDANOSINE W5J NRTI

54569564300 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

54868197400 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54868197402 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54868197403 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

54868249901 HIVID 0.375 MG TABLET

ZALCITABINE W5J NRTI

54868250001 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

54868250002 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

54868250200 VIDEX 100 MG TABLET CHEWABLE

DIDANOSINE/CALCIUM CARB/MAG

W5J NRTI

54868250401 RETROVIR 10 MG/ML SYRUP

ZIDOVUDINE W5J NRTI

54868335200 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 54868335201 ZERIT 40 MG CAPSULE STAVUDINE W5J NRTI 54868335300 ZERIT 20 MG CAPSULE STAVUDINE W5J NRTI

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54868336000 ZERIT 15 MG CAPSULE STAVUDINE W5J NRTI 54868344800 ZERIT 30 MG CAPSULE STAVUDINE W5J NRTI 54868369300 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 54868369302 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 54868452200 ZIAGEN 300 MG

TABLET ABACAVIR SULFATE

W5J NRTI

54868452201 ZIAGEN 300 MG TABLET

ABACAVIR SULFATE

W5J NRTI

54868466600 VIDEX EC 400 MG CAP SA

DIDANOSINE W5J NRTI

54868485300 EMTRIVA 200 MG CAPSULE

EMTRICITABINE W5J NRTI

54868541600 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 54868546400 DIDANOSINE 250 MG

DR CAPSULE DIDANOSINE W5J NRTI

54868559500 VIDEX EC 250 MG CAP SA

DIDANOSINE W5J NRTI

55045220701 HIVID 0.750 MG TABLET

ZALCITABINE W5J NRTI

55045354901 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

55175449401 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58016068900 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 58016068930 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 58016068960 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 58016068990 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 58016069000 RETROVIR 100 MG

CAPSULE ZIDOVUDINE W5J NRTI

58016069018 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58016069030 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58016069060 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58016069090 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58016079500 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 58016079530 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 58016079560 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 58016079590 EPIVIR 300 MG TABLET LAMIVUDINE W5J NRTI 58016086400 RETROVIR 300 MG

TABLET ZIDOVUDINE W5J NRTI

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58016086430 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

58016086460 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

58016086490 RETROVIR 300 MG TABLET

ZIDOVUDINE W5J NRTI

58864046230 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58864046260 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

58864046293 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

61958060101 EMTRIVA 200 MG CAPSULE

EMTRICITABINE W5J NRTI

61958060201 EMTRIVA 10 MG/ML SOLUTION

EMTRICITABINE W5J NRTI

62584004611 DIDANOSINE 250 MG DR CAPSULE

DIDANOSINE W5J NRTI

62584004621 DIDANOSINE 250 MG DR CAPSULE

DIDANOSINE W5J NRTI

62584004811 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

62584004821 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

63304092060 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

65862002460 ZIDOVUDINE 300 MG TABLET

ZIDOVUDINE W5J NRTI

65862004824 ZIDOVUDINE 50 MG/5 ML SYRUP

ZIDOVUDINE W5J NRTI

65862010701 ZIDOVUDINE 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

65862031030 DIDANOSINE 125 MG DR CAPSULE

DIDANOSINE W5J NRTI

65862031130 DIDANOSINE 200 MG DR CAPSULE

DIDANOSINE W5J NRTI

65862031230 DIDANOSINE 250 MG DR CAPSULE

DIDANOSINE W5J NRTI

65862031330 DIDANOSINE 400 MG DR CAPSULE

DIDANOSINE W5J NRTI

67253010910 ZIDOVUDINE 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

67253096124 ZIDOVUDINE 50 MG/5 ML SYRUP

ZIDOVUDINE W5J NRTI

68030605901 RETROVIR 100 MG CAPSULE

ZIDOVUDINE W5J NRTI

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68030606001 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 68030606401 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 68030606501 RETROVIR 100 MG

CAPSULE ZIDOVUDINE W5J NRTI

68258910801 EPIVIR 150 MG TABLET LAMIVUDINE W5J NRTI 68258912601 ZERIT 20 MG CAPSULE STAVUDINE W5J NRTI 00009376103 RESCRIPTOR 100 MG

TABLET DELAVIRDINE MESYLATE

W5K NNRTI

00009757601 RESCRIPTOR 200 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

00054390558 VIRAMUNE 50 MG/5 ML SUSP

NEVIRAPINE W5K NNRTI

00054464721 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00054464725 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00054864725 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00056047030 SUSTIVA 50 MG CAPSULE

EFAVIRENZ W5K NNRTI

00056047330 SUSTIVA 100 MG CAPSULE

EFAVIRENZ W5K NNRTI

00056047492 SUSTIVA 200 MG CAPSULE

EFAVIRENZ W5K NNRTI

00056051030 SUSTIVA 600 MG TABLET

EFAVIRENZ W5K NNRTI

00597004601 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00597004660 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00597004661 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

00597004724 VIRAMUNE 50 MG/5 ML SUSP

NEVIRAPINE W5K NNRTI

35356006990 SUSTIVA 200 MG CAPSULE

EFAVIRENZ W5K NNRTI

35356007106 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

35356007160 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

35356007224 VIRAMUNE 50 MG/5 ML SUSP

NEVIRAPINE W5K NNRTI

35356011506 SUSTIVA 600 MG TABLET

EFAVIRENZ W5K NNRTI

35356011530 SUSTIVA 600 MG EFAVIRENZ W5K NNRT

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141

TABLET I 54569456100 VIRAMUNE 200 MG

TABLET NEVIRAPINE W5K NNRT

I 54569456101 VIRAMUNE 200 MG

TABLET NEVIRAPINE W5K NNRT

I 54569456200 RESCRIPTOR 100 MG

TABLET DELAVIRDINE MESYLATE

W5K NNRTI

54569461100 SUSTIVA 200 MG CAPSULE

EFAVIRENZ W5K NNRTI

54569512200 RESCRIPTOR 200 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

54569537400 SUSTIVA 600 MG TABLET

EFAVIRENZ W5K NNRTI

54569560200 RESCRIPTOR 200 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

54868384400 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

54868384401 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

54868452000 RESCRIPTOR 200 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

54868466800 SUSTIVA 600 MG TABLET

EFAVIRENZ W5K NNRTI

54868586400 INTELENCE 100 MG TABLET

ETRAVIRINE W5K NNRTI

55289039203 VIRAMUNE 200 MG TABLET

NEVIRAPINE W5K NNRTI

59676057001 INTELENCE 100 MG TABLET

ETRAVIRINE W5K NNRTI

63010002036 RESCRIPTOR 100 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

63010002118 RESCRIPTOR 200 MG TABLET

DELAVIRDINE MESYLATE

W5K NNRTI

68258902001 SUSTIVA 600 MG TABLET

EFAVIRENZ W5K NNRTI

68258902101 SUSTIVA 200 MG CAPSULE

EFAVIRENZ W5K NNRTI

00173059500 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

00173059502 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

00173069100 TRIZIVIR TABLET ABACAVIR/LAMIVUDINE/ZIDOVUDINE

W5L NRTI

00173069120 TRIZIVIR TABLET ABACAVIR/LAMIV W5L NRTI

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142

UDINE/ZIDOVUDINE

00173074200 EPZICOM TABLET ABACAVIR SULFATE/LAMIVUDINE

W5L NRTI

16590006106 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

23490708706 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

35356010906 EPZICOM TABLET ABACAVIR SULFATE/LAMIVUDINE

W5L NRTI

35356010930 EPZICOM TABLET ABACAVIR SULFATE/LAMIVUDINE

W5L NRTI

35356011606 TRIZIVIR TABLET ABACAVIR/LAMIVUDINE/ZIDOVUDINE

W5L NRTI

35356011660 TRIZIVIR TABLET ABACAVIR/LAMIVUDINE/ZIDOVUDINE

W5L NRTI

49999006206 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

49999006210 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

49999006260 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054602 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054603 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054604 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054606 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054608 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054610 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054614 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054615 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054620 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

52959054628 COMBIVIR TABLET LAMIVUDINE/ZIDO W5L NRTI

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VUDINE 54569452400 COMBIVIR TABLET LAMIVUDINE/ZIDO

VUDINE W5L NRTI

54569452401 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54569452402 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54569452403 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54569519100 TRIZIVIR TABLET ABACAVIR/LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54569559400 EPZICOM TABLET ABACAVIR SULFATE/LAMIVUDINE

W5L NRTI

54868411400 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54868411406 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

54868560000 EPZICOM TABLET ABACAVIR SULFATE/LAMIVUDINE

W5L NRTI

55175520706 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55289038904 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55289038906 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55289038914 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55289038920 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55887023130 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55887023160 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

55887023190 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

58016069800 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

58016069830 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

58016069860 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

58016069890 COMBIVIR TABLET LAMIVUDINE/ZIDO W5L NRTI

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VUDINE 60760059504 COMBIVIR TABLET LAMIVUDINE/ZIDO

VUDINE W5L NRTI

60760059514 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

62682104801 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

66267050906 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

68030728301 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

68115009006 COMBIVIR TABLET LAMIVUDINE/ZIDOVUDINE

W5L NRTI

68258915801 TRIZIVIR TABLET ABACAVIR/LAMIVUDINE/ZIDOVUDINE

W5L NRTI

00074052260 KALETRA 100-25 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

00074395646 KALETRA 400-100/5 ML ORAL SOLU

RITONAVIR/LOPINAVIR

W5M PI

00074395977 KALETRA 133.3-33.3 MG SOFTGEL

RITONAVIR/LOPINAVIR

W5M PI

00074679922 KALETRA 200-50 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

35356011160 KALETRA 100-25 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

35356011201 KALETRA 200-50 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

35356011230 KALETRA 50-200 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

52959096812 KALETRA 100-25 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

54569514200 KALETRA SOFTGEL RITONAVIR/LOPINAVIR

W5M PI

54569552500 KALETRA ORAL SOLUTION

RITONAVIR/LOPINAVIR

W5M PI

54569575200 KALETRA 200-50 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

54868452400 KALETRA 133.3-33.3 MG SOFTGEL

RITONAVIR/LOPINAVIR

W5M PI

54868556600 KALETRA 200-50 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

55045348201 KALETRA 200-50 MG TABLET

RITONAVIR/LOPINAVIR

W5M PI

55289093118 KALETRA SOFTGEL RITONAVIR/LOPIN W5M PI

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AVIR 55289094712 KALETRA 200-50 MG

TABLET RITONAVIR/LOPINAVIR

W5M PI

00004038039 FUZEON CONVENIENCE KIT

ENFUVIRTIDE W5N FI

35356020660 FUZEON CONVENIENCE KIT

ENFUVIRTIDE W5N FI

54569578100 FUZEON CONVENIENCE KIT

ENFUVIRTIDE W5N FI

35356007006 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

35356007030 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

52959096903 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

54569558800 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

54868514100 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

55045348103 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

61958070101 TRUVADA TABLET EMTRICITABINE/TENOFOVIR

W5O NRTI

00597000201 APTIVUS 100 MG/ML SOLUTION

TIPRANAVIR/VITAMIN E TPGS

W5P PI

00597000302 APTIVUS 250 MG CAPSULE

TIPRANAVIR W5P PI

35356011301 PREZISTA 300 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

35356011330 PREZISTA 300 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

35356028460 PREZISTA 600 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

54569581400 PREZISTA 300 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

54868563100 PREZISTA 300 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

59676056001 PREZISTA 300 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

59676056101 PREZISTA 400 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

59676056201 PREZISTA 600 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

59676056301 PREZISTA 75 MG TABLET

DARUNAVIR ETHANOLATE

W5P PI

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146

00069080760 SELZENTRY 150 MG TABLET

MARAVIROC W5T CCR5

00069080860 SELZENTRY 300 MG TABLET

MARAVIROC W5T CCR5

35356020860 SELZENTRY 150 MG TABLET

MARAVIROC W5T CCR5

35356020960 SELZENTRY 300 MG TABLET

MARAVIROC W5T CCR5

54868580900 SELZENTRY 300 MG TABLET

MARAVIROC W5T CCR5

00006022761 ISENTRESS 400 MG TABLET

RALTEGRAVIR POTASSIUM

W5U INSTI

35356011006 ISENTRESS 400 MG TABLET

RALTEGRAVIR POTASSIUM

W5U INSTI

35356011060 ISENTRESS 400 MG TABLET

RALTEGRAVIR POTASSIUM

W5U INSTI

54569603400 ISENTRESS 400 MG TABLET

RALTEGRAVIR POTASSIUM

W5U INSTI

54868011700 ISENTRESS 400 MG TABLET

RALTEGRAVIR POTASSIUM

W5U INSTI

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Appendix B: CPT Codes used to identify HIV/AIDS

TABLE A2: Current Procedural Terminology Codes used to identify HIV/AIDS

CPT Code CPT Label 86359 T cells, total count 86360 T cells, total count, absolute CD4 and CD8, including ratio 88180 T cells, total count, absolute CD4 count 87901 Infectious agent genotype analysis by nucleic aceid (DNA

or RNA); HIV 1, reverse transcriptase and protease

87903 Infectious agent phenotype analysis by nucleic acid (DNA or RNA); with drug resistance tissue culture analysis; HIV 1; first through 10 drugs tested

87904 Infectious agent phenotype analysis by nucleic acid (DNA or RNA); with drug resistance tissue culture analysis; HIV 1; each additional 1 through 5 drugs tested (listed separately in addition to the code for the primary procedure) to be used in conjunction with code 87903

0023T Infectious agent drug susceptibility phenotype prediction using geontypic comparison to known genotypic/phenotypic database, HIV 1

87999 CCR5 Co-receptor Trofile- test is used to determine whether a person's HIV strains use the CCR5 or CXCR4 co-receptors, or both, to enter CD4 T-cells. CCR5 antagonists such as maraviroc (Selzentry) should not be used by people with CXCR4-tropic or dual/mixed-tropic virus.

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Appendix C: International Classification of Diseases, Ninth Revision, Clinical Modification codes used to identify HIV/AIDS

TABLE A3: International Classification of Diseases, Ninth Revision, Clinical Modification codes used to identify HIV/AIDS

ICD-9-CM ICD-9-CM Label AIDS Defining?

042. AIDS with specified conditions 042.0 AIDS with specified infections (no longer assigned) 042.1 AIDS causing other specified infections (no longer assigned) 042.2 AIDS with specified malignant neoplasms (no longer

assigned)

042.9 AIDS, unspecified (no longer assigned) 043. HIV infection causing other specified conditions (no longer

assigned)

043.0 HIV infection causing lymphadenopathy (no longer assigned)

043.1 HIV infection causing specified diseases of the CNS (no longer assigned)

043.2 HIV infection causing other disorders involving the immune mechanism (no longer assigned)

043.3 HIV infection causing other specified conditions (no longer assigned)

043.9 AIDS related complex, unspecified (no longer assigned) 044. Other HIV infection (no longer assigned) 044.9 HIV infection, unspecified (no longer assigned) 795.8 Positive serological or viral culture findings for HIV 795.71 Nonspecified serological evidence of HIV V08. Asymptomatic HIV infection status 112.4 Candidiasis of lung Yes 112.84 Candidiasis of esophagus Yes 180. Malignant neoplasm of cervic uteri Yes 180.0 Malignant neoplasm of cervic uteri, endocervix Yes 180.1 Malignant neoplasm of cervic uteri, exocervix Yes 180.8 Malignant neoplasm of cervic uteri, other specified sites of

cervix Yes

180.9 Malignant neoplasm of cervic uteri, unspecified Yes 114. Coccidioidomycosis Yes 114.0 Primary coccidioidomycosis, pulmonary Yes 114.1 Primary extrapulmonary coccidioidomycosis Yes 114.2 Coccidioidal meningitis Yes

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114.3 Other forms of coccidioidomycosis Yes 114.4 Chronic pulmonary coccidioidomycosis Yes 114.5 Pulmonary coccidioidomycosis, unspecified Yes 114.9 Coccidioidomycosis, unspecified Yes 117.5 Cryptococcosis, extrapulmonary Yes 078.5 Cytomegalovirus disease Yes 115. - 115.99

Histoplasma capsulatum Yes

176. Kaposi's Sarcoma Yes 176.0 Kaposi's Sarcoma, skin Yes 176.1 Kaposi's Sarcoma, soft tissue Yes 176.2 Kaposi's Sarcoma, palate Yes 176.3 Kaposi's Sarcoma, gastrointestinal sites Yes 176.4 Kaposi's Sarcoma, lung Yes 176.5 Kaposi's Sarcoma, lymph nodes Yes 176.8 Kaposi's Sarcoma, other specified sites Yes 176.9 Kaposi's Sarcoma, unspecified Yes 200.2 Burkitt's tumor or lymphoma Yes 200.8 Lymphosarcoma and reticulosarcoma, other named variants Yes 031.2 Diseases due to other mycobacteria, pulmonary Yes 202.8 Other lymphoma Yes 031.2 Mycobacterial disease, disseminated Yes 10.0 - 18.9 Mycobacterium tuberculosis, any site (pulmonary or

extrapulmonary) Yes

136.3 Pnuemocystis carinaii pneumonia Yes 046.3 Progressive multifocal leukoencephalopathy Yes 130.0 Meningoencephalitis due to taxoplasmosis Yes 799.4 Cachexia Yes

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Appendix D: Florida county median household income, rural or urban designation, and Agency for Health Care Administration county codes

TABLE A4: Florida county median household income, rural or urban designation, and Agency for Health Care Administration county codes

County Median Income Rural versus Urban

Medicaid County Code

Calhoun County 29,642 R 7 Dixie County 31,426 R 15 Putnam County 33,711 U 54 Holmes County 33,868 R 30 Highlands County 33,902 R 28 Suwannee County 34,157 R 61 Washington County 35,090 R 67 Levy County 35,294 R 38 Gadsden County 35,423 R 20 Hamilton County 35,632 R 24 Taylor County 35,900 R 62 Jackson County 36,442 R 32 Madison County 36,682 R 40 DeSoto County 37,226 R 14 Hendry County 37,354 R 26 Citrus County 37,807 U 9 Franklin County 38,436 R 19 Gulf County 38,574 R 23 Okeechobee County 38,643 R 47 Hardee County 38,865 R 25 Columbia County 39,078 R 12 Glades County 39,260 R 22 Alachua County 39,345 U 1 Liberty County 39,583 R 39 Marion County 40,306 U 42 Bradford County 40,519 U 4 Union County 40,694 R 63 Sumter County 41,010 U 60 Gilchrist County 41,048 R 21 Hernando County 42,457 U 27 Leon County 42,889 U 37 Miami-Dade County 42,969 U 13

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Escambia County 43,148 U 17 Volusia County 43,326 U 64

Pasco County 43,690 U 51 Jefferson County 44,011 R 33 Polk County 44,043 U 53 Charlotte County 44,639 U 8 Lake County 44,837 U 35 Pinellas County 44,838 U 52 Walton County 46,159 R 66 Bay County 46,240 R 3 Baker County 46,315 R 2 Osceola County 46,315 U 49 Indian River County 46,550 U 31 Lafayette County 46,551 R 34 St. Lucie County 46,656 U 56 Flagler County 47,573 U 18 Manatee County 47,935 U 41 Sarasota County 49,013 U 58 Brevard County 49,114 U 5 Duval County 49,135 U 16 Hillsborough County 49,594 U 29 Orange County 50,352 U 48 Lee County 50,362 U 36 Broward County 51,731 U 6 Wakulla County 52,353 R 65 Martin County 52,734 U 43 Palm Beach County 53,538 U 50 Okaloosa County 53,741 U 46 Santa Rosa County 54,250 U 57 Monroe County 54,946 R 44 Nassau County 57,907 U 45 Collier County 58,133 U 11 Seminole County 58,313 U 59 Clay County 60,352 U 10 St. Johns County 63,630 U 55

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Appendix E: Depression, anxiety or somatoform diagnoses, alcohol abuse and/or substance abuse, or severe mental illness diagnoses

TABLE A5: Depression, anxiety or somatoform diagnoses (DEP_ANX), alcohol abuse and/or substance abuse (AASA), or severe mental illness (SMI) diagnoses

Diagnosis Category Variable ICD-9 Schizophrenia schizophrenia SMI 295.xx Major depressive affective disorder, single episode, with psychotic behavior

depression SMI 296.24

Major depressive affective disorder, recurrent, with psychotic behavior

depression SMI 296.34

Manic disorder, single episode bipolar disorder

SMI 296.0x

Bipolar affective disorder, manic bipolar disorder

SMI 296.4x

Bipolar affective disorder, mixed bipolar disorder

SMI 296.6x

Bipolar affective disorder depressed bipolar disorder

SMI 296.5x

Bipolar affective disorder, unspecified bipolar disorder

SMI 296.7

Manic-depressive psychosis, other bipolar disorder

SMI 296.89

Affective personality disorder, cyclothymic disorder

bipolar disorder

SMI 301.13

Manic-depressive psychosis, unspecified bipolar disorder

SMI 296.8

Organic affective syndrome bipolar disorder

SMI 293.83

Unspecified affective psychosis bipolar disorder

SMI 296.90

Major depressive affective disorder single episode unspecified degree

Depression DEP_ANX 296.20

Major depressive affective disorder single episode mild degree

Depression DEP_ANX 296.21

Major depressive affective disorder single episode moderate degree

Depression DEP_ANX 296.22

Major depressive affective disorder single episode severe degree without psychotic behavior

Depression DEP_ANX 296.23

Major depressive affective disorder single episode in partial or unspecified remission

Depression DEP_ANX 296.25

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Major depressive affective disorder single episode in full remission

Depression DEP_ANX 296.26

Major depressive affective disorder recurrent episode unspecified degree

Depression DEP_ANX 296.30

Major depressive affective disorder recurrent episode mild degree

Depression DEP_ANX 296.31

Major depressive affective disorder recurrent episode moderate degree

Depression DEP_ANX 296.32

Major depressive affective disorder recurrent episode severe degree without psychotic behavior

Depression DEP_ANX 296.33

Major depressive affective disorder recurrent episode in partial or unspecified remission

Depression DEP_ANX 296.35

Major depressive affective disorder recurrent episode in full remission

Depression DEP_ANX 296.36

Neurotic depression Depression DEP_ANX 300.4 Depressive disorder, not elsewhere classified Depression DEP_ANX 311 Panic disorder without agoraphobia Anxiety DEP_ANX 300.01 Panic disorder with agoraphobia Anxiety DEP_ANX 300.21 Agoraphobia without a history of panic disorder

Anxiety DEP_ANX 300.22

Social phobia (social anxiety disorder) Anxiety DEP_ANX 300.23 Obsessive-compulsive disorder Anxiety DEP_ANX 300.3 Posttraumatic stress disorder Anxiety DEP_ANX 309.81 Acute stress disorder Anxiety DEP_ANX 308.3 Generalized anxiety disorder Anxiety DEP_ANX 300.02 Anxiety disorder due to general medical condition

Anxiety DEP_ANX 293.89

Anxiety disorder not otherwise specified Anxiety DEP_ANX 300.00

Somatization disorder Somatoform disorders

DEP_ANX 300.81

Undifferentiated somatoform disorder Somatoform disorders

DEP_ANX 300.82

Other somatoform disorders Somatoform disorders

DEP_ANX 300.89

Acute alcoholic intoxication in alcoholism unspecified drinking behavior

Alcohol abuse AASA 303.00

Acute alcoholic intoxication in alcoholism continuous drinking behavior

Alcohol abuse AASA 303.01

Acute alcoholic intoxication in alcoholism episodic drinking behavior

Alcohol abuse AASA 303.02

Acute alcoholic intoxication in alcoholism in remission

Alcohol abuse AASA 303.03

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Other and unspecified alcohol dependence unspecified drinking behavior

Alcohol abuse AASA 303.90

Other and unspecified alcohol dependence continuous drinking behavior

Alcohol abuse AASA 303.91

Other and unspecified alcohol dependence episodic drinking behavior

Alcohol abuse AASA 303.92

Other and unspecified alcohol dependence in remission

Alcohol abuse AASA 303.93

Opioid type dependence unspecified use Substance abuse

AASA 304.00

Opioid type dependence continuous use Substance abuse

AASA 304.01

Opioid type dependence episodic use Substance abuse

AASA 304.02

Opioid type dependence in remission Substance abuse

AASA 304.03

sedative, hypnotic or anxiolytic dependence unspecified use

Substance abuse

AASA 304.10

sedative, hypnotic or anxiolytic dependence continuous use

Substance abuse

AASA 304.11

sedative, hypnotic or anxiolytic dependence episodic use

Substance abuse

AASA 304.12

sedative, hypnotic or anxiolytic dependence in remission

Substance abuse

AASA 304.13

Cocaine dependence unspecified use Substance abuse

AASA 304.20

Cocaine dependence continuous use Substance abuse

AASA 304.21

Cocaine dependence episodic use Substance abuse

AASA 304.22

Cocaine dependence in remission Substance abuse

AASA 304.23

Cannabis dependence unspecified use Substance abuse

AASA 304.30

Cannabis dependence continuous use Substance abuse

AASA 304.31

Cannabis dependence episodic use Substance abuse

AASA 304.32

Cannabis dependence in remission Substance abuse

AASA 304.33

Amphetamine and other psychostimulant dependence unspecified use

Substance abuse

AASA 304.40

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Amphetamine and other psychostimulant dependence continuous use

Substance abuse

AASA 304.41

Amphetamine and other psychostimulant dependence episodic use

Substance abuse

AASA 304.42

Amphetamine and other psychostimulant dependence in remission

Substance abuse

AASA 304.43

Hallucinogen dependence unspecified use Substance abuse

AASA 304.50

Hallucinogen dependence continuous use Substance abuse

AASA 304.51

Hallucinogen dependence episodic use Substance abuse

AASA 304.52

Hallucinogen dependence in remission Substance abuse

AASA 304.53

Other specified drug dependence unspecified use

Substance abuse

AASA 304.60

Other specified drug dependence continuous use

Substance abuse

AASA 304.61

Other specified drug dependence episodic use Substance abuse

AASA 304.62

Other specified drug dependence in remission Substance abuse

AASA 304.63

Combinations of opioid type drug with any other drug dependence unspecified use

Substance abuse

AASA 304.70

Combinations of opioid type drug with any other drug dependence continuous use

Substance abuse

AASA 304.71

Combinations of opioid type drug with any other drug dependence episodic use

Substance abuse

AASA 304.72

Combinations of opioid type drug with any other drug dependence in remission

Substance abuse

AASA 304.73

Combinations of drug dependence excluding opioid type drug unspecified use

Substance abuse

AASA 304.80

Combinations of drug dependence excluding opioid type drug continuous use

Substance abuse

AASA 304.81

Combinations of drug dependence excluding opioid type drug episodic use

Substance abuse

AASA 304.82

Combinations of drug dependence excluding opioid type drug in remission

Substance abuse

AASA 304.83

Unspecified drug dependence Substance abuse

AASA 304.90

Unspecified drug dependence continuous use Substance abuse

AASA 304.91

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Unspecified drug dependence episodic use Substance abuse

AASA 304.92

Unspecified drug dependence in remission Substance abuse

AASA 304.93

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Appendix F: Expenditure-predictive diagnosis groups and key comorbidities

TABLE A6: Expenditure-predictive diagnosis groups and key comorbidities among previously ART naïve Medicaid-insured PLWHA (n=502)

Diagnosis Dx ICD-9 Freq % COM1 Acute poliomyelitis 1 045 0 0.0% COM2 Viral hepatitis 1 070 75 14.9% COM3 Congenital syphilis 1 090 0 0.0% COM4 Early syphilis, symptomatic 1 091 0 0.0% COM5 Early syphilis, latent 1 092 0 0.0% COM6 Cardiovascular syphilis 1 093 0 0.0% COM7 Neurosyphilis 1 094 0 0.0% COM8 Other forms of late syphilis, with

symptoms 1 095 0 0.0%

COM9 Late syphilis, latent 1 096 0 0.0% COM10 Other and unspecified syphilis 1 097 22 4.4% COM11 Toxoplasmosis 1 130 4 0.8% COM12 Nutritional Deficiencies 1 260-269 27 5.4% COM13 Disorders of fluid, electrolyte, and

acid-base balance 1 276 87 17.3%

COM14 Chorioretinal inflammations, scars, and other disorders of choroid

1 728 32 6.4%

COM15 Symptoms concerning nutrition, metabolism, and development

1 783 40 8.0%

COM16 Cachexia / Wasting Disease 1 799.4 32 6.4% COM17 Hypertensive renal disease 1 403,404 23 4.6% COM18 Acute and chronic renal failure 1 584-588 67 13.3% COM19 Acute and subacute endocarditis 1 421 3 0.6% COM20 Symptoms involving digestive

system 1 787 185 36.9%

COM21 Diseases due to other mycobacteria 2 031 0 0.0% COM22 Cryptococcosis 2 117.5 3 0.6% COM23 Pneumocystosis 2 136.3 20 4.0% COM24 Aplastic anemia 2 284 25 5.0% COM25 Purpura and other hemorrhagic

conditions 2 287 25 5.0%

COM26 Diseases of white blood cells 2 288 58 11.6% COM27 Mental Retardation 2 317,318,319 4 0.8% COM28 Bacterial meningitis 2 320 1 0.2% COM29 Other cerebral degenerations 2 321 0 0.0% COM30 Meningitis of unspecified cause 2 322 2 0.4% COM31 Other cerebral degenerations 2 331 9 1.8%

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COM32 Chorioretinal inflammations, scars, and other disorders of choroid

2 363 15 3.0%

COM33 Other diseases of pericardium 2 423 5 1.0% COM34 Acute, but ill-defined,

cerebrovascular disease 2 436 20 4.0%

COM35 Viral pneumonia 2 480 6 1.2% COM36 Pneumococcal pneumonia 2 481 14 2.8% COM37 Other bacterial pneumonia 2 482 15 3.0% COM38 Pneumonia due to other specified

organism 2 483 3 0.6%

COM39 Bronchopneumonia, organism unspecified

485 0 0.0%

COM40 Pneumonia, organism unspecified 2 486 109 21.7% COM41 Pneumonia, organism unspecified 2 492 12 2.4% COM42 Emphysema 2 511 31 6.2% COM43 Pleurisy 2 518 90 17.9% COM44 Other diseases of the lung 2 578 42 8.4% COM45 Gastrointestinal hemorrhage 2 648 30 6.0% COM46 Other conditions in the mother

complicating pregnancy 2 707 20 4.0%

COM47 Chronic ulcer of skin 2 781 33 6.6% COM48 Symptoms involving nervous and

musculoskeletal systems 3 046.3 2 0.4%

COM49 Progressive multifocal leukoencephalopathy

3 348.3 18 3.6%

COM50 Unspecified encephalopathy 3 416.0 10 2.0% COM51 Primary pulmonary hypertension 3 428 35 7.0% COM52 Heart failure 3 512 4 0.8% COM53 Pneumothorax 3 514 18 3.6% COM54 Pulmonary congestion and

hypostasis 3 516 3 0.6%

COM55 Other alveolar and parietoalveolar pneumonopathy

3 560 18 3.6%

COM56 Intestinal obstruction without mention of hernia

3 730 10 2.0%

COM57 Septicemia 4 038 33 6.6% COM58 Cytomegaloviral disease 4 078.5,484,

573.1 12 2.4%

COM59 Malignant neoplasm of trachea, bronchus, and lung

4 162 2 0.4%

COM60 Intracranial and intraspinal abscess 4 324 2 0.4% COM61 Epilepsy 4 345 35 7.0% COM62 Inflammatory and toxic neuropathy 4 357 19 3.8%

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COM63 Subarachnoid hemorrhage 4 430 3 0.6% COM64 Intracerebral hemorrhage 4 431 3 0.6% COM65 Bronchiectasis 4 494 1 0.2% COM66 Peritonitis 4 567 4 0.8% COM67 Hydronephrosis 4 591 9 1.8% COM69 Histoplasmosis 5 115 1 0.2% COM70 Lymphoid leukemia 5 204-206, 208 2 0.4% COM71 Diabetes with renal manifestations 5 250.4 11 2.2% COM72 Coagulation defects 5 286 12 2.4% COM73 Other paralytic syndromes 5 344 6 1.2% COM76 Polyarteritis nodosa and allied

conditions 5 446 1 0.2%

COM77 Lymphosarcoma and reticulosarcoma

6 200 4 0.8%

Key comorbidities and diagnosis groups defined by Fakhraei, S.H., Kaelin, J.J., & Consiver, R. (2001). Comorbidity-Based Payment Methodology for Medicaid Enrollees with HIV/AIDS. Health Care Financing Review, 23(2), 53–69.

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Appendix G: Institutional Review Board Approvals

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