Characterization of Self-reported Asthma in Morbidly Obese Women

Presented By: Alton R. Johnson Jr.

Outline Asthma

Pathophysiology, epidemiology, & diagnosis

Obesity Definition, trends, morbidity

Obesity & asthma association Supporting evidence

Summer Research Project

Pathophysiology Asthma

Inflammation

Airway Hyperresponsiveness

Airway Obstruction

Clinical symptoms

Epidemology of asthma One of the most common chronic

respiratory diseases affects approx. 7% of population (22

million) (CDC, 2010)▪ 27% are children (>6 million) (CDC, 2010)

Associated with significant morbidity▪ African American children have a 250%

higher hospitalization rate and a 500% higher death rate (CDC, 2010)

Asthma: Prevalence Prevalence = (# of people with the disease) / (# of people

at risk for disease + # of people with the disease) Increasing prevalence over past 20 years (NAEPP, 2010) Significant disparity.

Obesity

Obesity Trends* Among U.S. AdultsBRFSS, 1990, 2008

(*BMI 30, or about 30 lbs. overweight for 5’4” person)

20081990

No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

Obesity and Asthma

Cross-sectional studies Increased prevalence of asthma in obese

patients Obesity associated with worst asthma control

and increased morbidity (severe symptoms)

Longitudinal studies Asthma risk increases by 50 % in overweight

and obese people AHR is associated with increased BMI

Obesity associated with increased risk of asthma

Beuther and Sutherland 2007

Obesity and Asthma Possible explanations:

Causal link▪ Obesity leads to increased risk of asthma▪ Inflammatory pathway▪Mechanical pathway

Coincidental▪ Epiphenomenon▪ Shared risk factors (i.e. genetic, environmental)

Diagnostic bias

Effects of obesity on asthma control/severity

Controversial findings Some studies showing worst asthma

symptoms in obese patients (Schacter et.al. 2001)

Others have not (Clerisme-Beaty et.al. 2009) Limited by use of self-report or

questionnaire to diagnose asthma

Obesity is associated with changes in lung volumes which may mimic asthma.

It is unclear whether the asthma phenotype is different in obese patients

Project Importance

To examine differences in pulmonary function profile, respiratory symptoms, and quality of life in morbidly obese women based on self-reported asthma.

Objective

53 participants were recruited to participate in the study. 11 were excluded based on gender, leaving 42 women in the final analysis.

Recruitment

Results

Baseline Demographics

General Health Survey Results

Respiratory Questionnaire

Pulmonary Function Profile

Air Hyperresponsiveness

24 participants (6 asthmatics, 18 non-asthmatics) 60% asthmatics had positive AHR

40% non-asthmatics had positive AHR

Conclusions Both Groups:

Decreased quality of life Increased reports of respiratory symptoms Trend for lower FEV1/FVC

Asthmatics: Significantly more respiratory complaints Lower quality of life

Symptoms rather than objective differences in respiratory function may guide the diagnosis of asthma in this population

Limitation

It is unclear whether these findings apply to men or patients with less severe obesity.

Acknowledgements Emmanuelle Clerisme-Beaty, MD MHS Mercedes Proctor, BA Andrew Bilderback, MS Cynthia Rand, PhD Flona Redway, PhD Denise Guise

Funding: NIH/NHLBI grant R25 HL084762, Johns Hopkins

University NIH grant K12RR01767, Johns Hopkins University NIH-NIGMS RISE Grant, R25 GM059244-09, Barry

University

Questions