Maternal Asthma Is an Independent Risk Factor for Long-Term Respiratory Morbidity of the Offspring

Objective The objective of this study was to investigate whether maternal bronchial asthma increases the risk for long-term respiratory morbidity of the offspring. Study Design A population-based cohort study compared the incidence of long-term pediatric hospitalizations due to respiratory disease of the offspring of mothers with and without bronchial asthma. Deliveries occurred between the years 1991 and 2014 in a tertiary medical center. Congenital malformations as well as multiple pregnancies were excluded. Kaplan-Meier's survival curve was used to estimate cumulative incidence of respiratory morbidity. A multivariate generalized estimating equation (GEE) logistic regression model analysis was used to control for confounders. Results During the study period, 253,808 deliveries met the inclusion criteria; of which 1.3% were born to mothers with bronchial asthma ( n =3,411). During the follow-up period, children born to women with bronchial asthma had a significantly higher rate of long-term respiratory morbidity (odds ratio [OR]=1.5; 95% confidence interval [CI]=1.3-1.7; p <0.001). Specifically, the rate of childhood asthma was higher among offspring of mothers with asthma (OR=2.3; 95% CI=1.8-2.9; p <0.001). Children born to women with asthma had higher cumulative incidence of respiratory morbidity, using a Kaplan-Meier's survival curve (log-rank test; p <0.001). Using two multivariable GEE logistic regression models, controlling for the time to event, maternal age, and gestational age at delivery, maternal bronchial asthma was found to be an independent risk factor for long-term respiratory disease of the offspring (adjusted OR=1.6; 95% CI=1.4-1.9; p <0.001), and specifically for bronchial asthma (adjusted OR=2.5; 95% CI=1.9-3.1; p <0.001). Conclusion Maternal bronchial asthma is an independent risk factor for long-term respiratory morbidity of the offspring.