Identifying critical windows of prenatal particulate air pollution exposure and children’s blood pressure at age 4-6

Abstract

TPS 671: Cardiometabolic effects of long-term air pollution exposure, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: Exposure to air pollution is associated with increased blood pressure (BP) in adults and children. Limited evidence suggests that air pollution exposure during the prenatal period may contribute to adverse cardiorenal health later in life. Here we apply a distributed lag model (DLM) approach to identify critical windows that may underlie the association between prenatal particulate matter ≤ 2.5 μm in diameter (PM2.5) and children’s BP at 4-6 years. Methods: Participants included 537 mother-child dyads enrolled in the longitudinal cohort study Programming Research in Obesity, GRowth, Environment, and Social Stress (PROGRESS) based in Mexico City. Prenatal daily PM2.5 exposure was estimated using a validated satellite-based spatio-temporal model and BP was measured using the automated Spacelabs system with a sized cuff. We used DLMs to examine associations between daily PM2.5 exposure and systolic BP (SBP), adjusting for child’s age, sex and BMI, as well as maternal education and indoor smoking report during the second and third trimester. Results: We found that PM2.5 exposure between weeks 17 to 35 of gestation (days 115 to 244) was significantly associated with children’s increased SBP. To place this into context, a constant 10 µg/m3 increase in PM2.5 sustained throughout this critical window would predict a cumulative increase of 1.4 mmHg (CI: 0.3, 2.5) in SBP at age 4-6. In a stratified analysis by sex, this association persisted in boys but not in girls. Conclusions: Second and third trimester PM2.5 exposure may increase children’s BP. Further work investigating PM2.5 exposure with BP and kidney function changes later in childhood will be important to understanding cardiorenal trajectories that may predict adult disease. Our results underscore the importance of reducing air pollution exposure among susceptible populations.