Condensation: A Retrospective Cohort Study to Investigate the Association Between Maternal Pre-pregnancy Obesity and Childhood Respiratory Disease

Objective We sought to explore whether maternal pre-pregnancy obesity is an independent risk factor for offspring respiratory morbidity during childhood. Methods A population-based retrospective cohort analysis comparing childhood respiratory morbidity incidence in offspring to mothers with pre-pregnancy obesity (BMI >= 30 kg/m(2)) and those who had lower BMI was conducted. Respiratory diagnoses were pre-defined based on ICD-9 codes. The study population comprises of all deliveries that took place at the Soroka University Medical Center (SUMC), the sole tertiary hospital in the Negev (Southern Israel), between the years 1991-2014. A Kaplan-Meier survival curve was used for cumulative respiratory morbidity incidences over time and a Cox proportional hazards model was constructed to control for confounders. Results During the study period, 242,342 infants met the inclusion criteria; out of which 3290 were born to mothers with a diagnosis of pre-pregnancy obesity. Offspring to mothers with pre-pregnancy obesity had a significant higher risk for obstructive sleep apnea (OR 1.43, 95% CI 1.002-2.046) as well as a higher total risk for hospitalizations due to childhood respiratory morbidity (OR 1.21, 95% CI 1.041-1.398). The cumulative respiratory morbidity incidence over time was significantly higher in the maternal pre-pregnancy obesity group (p = 0.044). Controlling for maternal age, gestational diabetes mellitus, hypertensive disorders and gestational age, pre-pregnancy obesity remained an independent risk factor for offspring respiratory morbidity (adjusted HR = 1.175, 95% CI 1.018-1.357). Conclusion Maternal pre-pregnancy obesity may create an environment leading to an increased risk for long-term offspring respiratory morbidity, and specifically obstructive sleep apnea.