Obesity and extreme obesity: new insights into the black-white disparity in neonatal mortality.
OBJECTIVE
To estimate whether the preponderance of obesity among black women could explain the black-white disparity in neonatal mortality.


METHODS
This is a population-based study using longitudinally collected data among pregnant women from the state of Missouri spanning almost two decades (1978-1997). Obesity is defined in this study as body mass index (BMI) of at least 30 and further categorized into the typically reported three subclasses: class I (BMI 30.0-34.9), class II (BMI 35.0-39.9), and extreme/morbid obesity (BMI at least 40). The main outcome measures were neonatal mortality, early neonatal mortality, and late neonatal mortality.


RESULTS
Overall, neonatal mortality and early neonatal mortality but not late neonatal mortality increased with higher obesity subclass, with the greatest risk registered among morbidly obese mothers (hazards ratio for neonatal mortality 1.3; 95% confidence interval [CI] 1.1-1.5; hazards ratio for early neonatal mortality 1.3; 95% CI 1.1-1.5). Among blacks, the risk for neonatal, early, and late neonatal mortality increased significantly with rising BMI (50-100% increments). However, offspring of obese white mothers had no elevated risks for any of the three indices of mortality regardless of maternal obesity subclass.


CONCLUSIONS
Neonates of obese black mothers have an elevated risk of mortality throughout the neonatal period, whereas those of obese white mothers do not. Obesity among black mothers may contribute to the persistent black-white disparity in infant survival in the United States and could provide an avenue for narrowing the black-white gap in infant mortality.


METHODS
II.
Department of Epidemiology and Biostatistics, University of South Florida, Tampa, Florida, USA. hamisu.salihu@gmail.com
Hamisu M
HM
Salihu
Amina P
AP
Alio
Roneé E
RE
Wilson
Puza P
PP
Sharma
Russell S
RS
Kirby
Greg R
GR
Alexander
D044383:Black People; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008923:Missouri / Q000453:epidemiology; D009765:Obesity / Q000453:epidemiology*; D009767:Obesity, Morbid / Q000453:epidemiology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D044465:White People; D001741:Black or African American