The Role of Antenatal Factors on Neonatal Outcome

Jonathan M. Davis, MD

Vice-Chair of Pediatrics, Chief of Newborn Medicine

Floating Hospital for Children/Tufts Medical Center

Professor of Pediatrics

Tufts University School of Medicine

Boston, MA

Chair, Child Health Oversight Committee, NIH

Chair, Neonatal Advisory Committee, FDA

No relevant financial relationships to disclose

Outpatient deck, 1906

6

1999

Obesity in the US – A Major Public Health Problem

2009

1990

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

CDC database

Obesity and Inflammation

Obesity is associated with marked inflammation and immune dysregulationAdipocytes undergo necrosis, promoting inflammation and macrophage recruitmentHigher circulating levels of TNF-α, IL-6, MCP-1, and TGF-β

Obesity in Pregnancy – Harmful to Mother and Infant

Schmatz et al, J Perinatology, 2010.

Obesity↑CRP ↑IL-6, IL-8↑TNFα↑leptin,↑adiponectin↑macrophages

Pregnancy↑CRP↑macrophages↑neutrophils↑IL-10

↑Inflammation

Disease

Maternal DisPre-eclampsiaGestational DMDysfunctional Labor

Lifetime Disease RiskHypertensionDMHyperlipidemiaMI

Neonatal DisLow ApgarsNICU admissionMacrosomiaPrematurity

Child/Adult DiseaseObesityDMMetabolic Syndrome

Obesity in Pregnancy is Associated with Increased Infections

Heslehurt et al. Obesity Reviews, 2008.

Obesity in Pregnancy

• Increased risks of antenatal, intrapartum, and neonatal complications

• 2-5 X increased risk of:• Diabetes

• Pre-eclampsia

• Induction of labor, emergency C-section

• Intrapartum & postpartum hemorrhage

• Chorioamnionitis

• Macrosomic infants, lower Apgars, NICU admissions

• Intrauterine death

Results: 1981-2005

• 219,173 pregnant women over 25 year period

• Mean maternal weight increased linearly → 139 lbs in 1981 to 161 lbs in 2005, or 22 pounds

• For 27 year old mothers only, mean weights increased 25 pounds in 25 years

Results

Medians (interquartile ranges); Kruskal-Wallis ANOVA test

Results

Major Risk Factors for Prematurity by Multivariate Analysis

• PROM

• Obesity

• Pre-existing diabetes

• Pre-eclampsia/hypertension

• Previous preterm/SGA infant

• In vitro fertilization

Obesity in Pregnancy Changes Immune Cell Populations

Cell Populations

Obese (n=15)

Lean (n=15)

p value

CD4+ (% lymphocytes)

45.8+9.4 44.3+12.7 ns

CD8+ (% lymphocytes)

16.4+5.8 23.5+7.4 <0.05

NKT cells 22.9+6.1 27.9+4.1 <0.05

B cells 21.9+6.2 13.3+5.3 <0.05

Maternal Obesity Impairs Cytokine Production

* p < 0.05

*

Interferon gamma response to stimulation

0

100

200

300

400

500

600

700

CD8+ cells CD4+ cells

geo

met

ric

mea

n (

MF

U)

Lean

Obese

**

TNF alpha response to stimulation

0

100

200

300

400

500

600

700

800

CD8+ cells CD4+ cells

geo

metr

ic m

ean

(M

FU

)

Lean

Obese

*

*

TNFα response to stimulation

IFNγ response to stimulation

*

* *

Obese Pregnant Women Have Reduced Micronutrients

Lean (n=15) Obese (n=15)

RBC folate (ng/ml)

1606+559 1131+446*

Vitamin C (mg/dL)

1.3+0.2 0.9+0.3*

Vitamin E (ug/dL)

1720+394 1393+282*

(1,25) OH Vitamin D (ng/ml)

34.8+10.2 27.4+8*

Fat (%)

Protein (%)

Carb (%)

Kcal/g Vit A (g/kg)

Vit C (g/kg)

Vit E (g/kg)

Selenium (g/kg)

Control 8 16 45 3.2 4,600 0 86 0.165

Control+ AOX

8 16 45 3.2 23,000 5.6 260 0.5

Western 16 21 50 4.3 4,600 0 86 0.165

Western+ AOX

16 22 50 4.3 23,000 5.6 260 0.5

Diet Composition for Dams

Offspring Adiposity at 2 weeks

0

5

10

15

20

25

Control Control+Aox Western Western+Aox

Fa

t P

erc

en

tag

e

*

** *

Conclusions

• Mean maternal weights have increased significantly over time

• Obesity in pregnancy - increased inflammation, immune dysregulation, PPROM, chorioamnionitis, and prematurity

• Obesity one of multiple factors that increases the risk of prematurity

Fetal Inflammatory

Response

time

Trimester II Delivery

Intrauterine

infection

Preterm

birth

Brain/Lung damage

Bacterial Infection within the Uterus

Markers of Preterm Delivery

Cervix / Vagina Amniotic Fluid Serum

Bacterial vaginosis WBC CRP

G-CSF G-CSF G-CSF

TNF- TNF- TNF-

IL-1 Glucose IL-6

IL-6 IL-6

IL-8 Bacteria

FFN

RISK FACTORS: INTRAPARTUM

• Fever

• Urinary tract infection

• Premature rupture of membranes

• Chorioamnionitis/funicitis (many organisms, e.g. ureaplasma)

• Low Apgars, encephalopathy, seizures, poor neonatal outcome

Adj OR : 3.8 (0.97-15)

Fever

No Fever

Cognitive Development

Infection in the Placenta and Neonatal Brain Injury

• Bacteria present >80% by PCR, no correlation with chorioamnionits/preterm labor

• Fetal inflammation needed for brain injury

• Role of endotoxin (LPS injections in rabbits), oxidative stress (deficiency of antioxidants), cytokines (CSF) in white matter injury

• Sensitizes fetal brain to hypoxia

• May have brain anomalies at birth

• In utero insult may continue post-partum

FIR: Role for White Cell Activation

Dammann O, et al. 2001

Pathogenetic Mechanisms in PVL

Maternal infection/ Prematurity Fetal inflammation

Cytokines Ischaemia/ Microglia reperfusion

Fe++ IVH Glutamate Antioxidants

Reactive oxygen species Reactive nitrogen species

Oligodendroglial death

Slide Courtesy of Alan Leviton

PVL on MRIincreased signal intensity in white matter,

volume loss in grey matter

Growth Factorsand Hormones

Long-term Disability

ChemokinesCytokines

AdhesionMolecules

?

PrenatalInfection

Inflammatory Response

White Matter Damage

Lung Injury

Other poor outcomes

Future Research• Molecular Epidemiology

Genetic polymorphisms Genetic susceptibility

• Directed TherapiesProtectors (antenatal steroids)Anti-inflammatory agents (IL-10, CC10, ibuprofen)Antioxidants (rhSOD)

• Maternal and Neonatal Conditions Chorioamnionitis/funicitis (new FHR monitors)BPD, PVL, ROP, NEC (salivary gene analyses)

• Laboratory Techniques (microarray, Luminex)

• Assessment Techniques (PFT, CT, MRI, EEG)

….

Neonatal Abstinence SyndromeNeonatal Abstinence Syndrome

• Opioid exposure in pregnancy - 5.6 infants/1,000 births

• Incidence has tripled in the past decade• The mother may also be smoking or

taking other medications • Signs of withdrawal in 60-80% of infants

exposed to opioids

• Dysfunction of the central nervous system, gastrointestinal tract, and/or respiratory system

Neonatal Abstinence Syndrome Neonatal Abstinence Syndrome

• Prolonged treatment in hospital, high healthcare costs

• Safety and efficacy of agents not well established

• Significant variability in the incidence and severity

• Factors influencing this variability are unknown

Neonatal Abstinence Syndrome

• Genetic factors may be important

• Single nucleotide polymorphisms (SNPs): Single base pair changes that can alter protein’s function

• SNPs influence opioid dosing, metabolism, and addiction in adults

• No prior studies of genetic links to NAS

Candidate Genes for NAS

• SNPs present in 40-50% of the population have been studied in adults

• Mu Opioid Receptor (OPRM1) = Site of Action

• 118A>G SNP

• Multi-Drug Resistance Gene (ABCB1) = Transporter

• 1236C>T SNP

• 3435C>T SNP

• 2677G/T/A SNP

• Catechol-O-methyltransferase (COMT) = Modulator

• 158A>G SNP

Methods• 86 opioid exposed term infants• Mothers receiving methadone or

buprenorphine

• Infants treated with morphine or methadone

• If severe - additional medications given

• A sample of blood or saliva collected from each infant

• Incidence and severity correlated with changes in genetic profiles

Results

DEMOGRAPHICS

White 98%

Maternal Methadone 64%

Maternal Buprenorphine 36%

Maternal Smoking 78%

Maternal Benzodiazepines 12%

LOS All Infants Mean 22.3 days

LOS Treated Infants Mean 31.6 days

Treatment for NAS 65%

Treated with >2 medications 24%

OPRM1 118A>G Results

• AA vs AG/GG infants compared in models that adjust for breastfeeding and study site

• Those with the AG/GG genotype - treated less frequently and had shorter LOS

OUTCOME UNADJUSTEDRESULTS

ADJUSTED RESULTS

P-VALUE

Infant Treated

72% vs 48% OR = 0.76 (CI 0.63, 0.96)

0.006

Mean LOS 24.1 vs 17.6 days - 8.5 days 0.009

COMT 158A>G Results

• AA infants vs AG/GG infants in models that adjusted for breastfeeding and site

• AG/GG infants were treated less frequently and had shorter LOS than AA infants

OUTCOME UNADJUSTED RESULTS

ADJUSTED RESULTS

P-VALUE

Infant Treated

88% vs 60% OR = 0.79(CI 0.61, 0.99)

0.02

Mean LOS 31.1 vs 20.4 days - 10.8 days 0.005

Conclusions• NAS is a complex disorder with many

factors contributing to the incidence and severity

• SNPs in the OPRM1 and COMT genes - reduced treatment and LOS

• No associations found with ABCB1 SNPs

• Combining clinical risk factors with genetic profiling would permit personalized genetic medicine and targeted treatment regimens

Challenges in Neonatal Drug Development

• Most drugs used in newborn infants not FDA approved - safety and efficacy not established

• Small market, high liability, ethical concerns

• Significant variability in NAS treatment protocols

• Many NAS medications include alcohol or propylene glycol

• Concern for adverse long-term developmental outcomes

Future Directions

• NIH Grant – “Improving Outcomes in Neonatal Abstinence Syndrome”

• Randomize infants to receive morphine or methadone (determine best practice)

• Evaluate long-term neurodevelopmental outcomes of infants treated for NAS

• Establish other genetic factors - Addiction Array (1350 SNPs for addiction disorders)