Prenatal Exposure to Stress and Lung Function in 8-10 year old Children

Abstract

Background Exposure to stress during pregnancy can have long term effects on children’s lung function. This association appears to be sex dependent and has been previously demonstrated in 4-6 year old children. The aim of this study was to evaluate sex dependent associations between pre-natal stress exposure and lung function in 8-10 year old children. Methods Data is from 182 mother-child pairs of the ongoing Programming Research in Obesity, Growth, Environment and Social Stressors (PROGRESS) cohort in Mexico City. Stress levels in mothers were assessed as negative life events using the Crisis in Family Systems Revised (CRISYS) questionnaire during pregnancy. The score (0-11) was dichotomized at the median (3). We visited the child’s home and performed spirometry tests according to American Thoracic Society guidelines. Results were overread by a pediatric pulmonologist. Spirometry results were analyzed using linear regression. Models were stratified by child’s sex, and adjusted for maternal pregnancy exposure to PM 2.5, age at birth and child’s gestational age, height and age at time of spirometry. Results We found significant positive associations between higher stress and improved lung function. The associations were stronger in girls compared to boys. For percent predicted FVC and FEV1 higher vs lower stress in boys (β:3.81, 95% CI [-1.60, 9.24]) and (β:2.33 , 95% CI [-3.42, 8.08]) vs girls (β:5.76 , 95% CI [0.92, 10.59]) and (β:5.00 , 95% CI [0.57, 9.43]). Conclusions Prenatal stress is positively associated with children’s lung function and appears to be sex-dependent with females demonstrating improved lung function compared to males. Results highlight the importance of considering susceptibility by sex in studies of chemical and stress co-exposures.