Prenatal PM2.5 Exposure and Neurodevelopment at 2 Years of Age in a Birth Cohort from Mexico City

摘要

Background: The association between fine particles (PM2.5) and child development has not been assessed based on the Bayley Scales of Infant Development III (BSID-III), in which cognitive and language functioning are analyzed separately. Objective: To examine longitudinally the association between prenatal PM2.5 exposure and cognitive, language and motor development during the first two years of children's life. Methods: Analysis was conducted in PROGRESS, a longitudinal birth cohort enrolled during 2007-2011 in Mexico City. We used mixed-effect regression models to evaluate cognitive, language and motor scores of the BSID-III in 24 month-old children (n=740). PM2.5 was estimated using a validated satellite-based spatio-temporally prediction model. We modeled associations of each of the 3 trimester-average exposures with neurodevelopmental assessment scores, adjusted for potential confounders. Results: In models adjusted by sex of the child, gestational age, birth weight, smoking and mother's IQ, an increase of lmg/m3 of PM2.5 predicted a decrease of cognitive and language scores. The most consistent results were in language assessments. At the 24 month follow-up, each unit increase in PM2.5, was associated with a decrease of the language function of -0.38 points (CI95%: -0.77, -0.01). Conclusion: Our findings suggest that language development up to 24 months of age, may be particularly sensitive to PM2.5 exposure during pregnancy.