Maternal exposure to air pollutants and childhood autism spectrum disorder in Taiwan

摘要

Autism spectrum disorders (ASD) is a group of neurodevelopmental disorders. Its etiology is not well known. To evaluate associations between maternal exposure to air pollutants during pregnancy and childhood ASD, we conducted a study of infants born between 1996 and 2000 identified from a cohort of one million individuals randomly sampled from the National Health Insurance Research Database of Taiwan. After excluding those who had missing data on insurance date and who lived outside the Taiwan Island, we included 62 919 children and followed them till 2013. We obtained data on air pollutants (ozone [03], carbon monoxide [CO], nitrogen dioxide [N02], sulfur dioxide, and particles with a diameter less than 10 nm [PM10]) measured by air quality monitoring stations established by the Environmental Protection Administration of Taiwan near the maternal residence during pregnancy. After adjusting for other risk factors, we observed positive associations between ASD and CO during the whole gestation period (hazard ratio [HR]=1.88, 95% confidence interval [CI]: 1.49-2.36, per ppm) as well as in the first (HR=1.93, 95%CI: 1.55-2.39), second (HR=1.77, 95%CI: 1.41-2.22), and third (HR=1.75, 95%CI: 1.39-2.21) trimesters individually. Similarly, positive associations were observed between ASD and N02 during the whole gestation period (HR=1.42, 95%CI: 1.22-1.66, per 10-ppb) as well as in the first (HR=1.39, 95%CI: 1.22-1.58), second (HR=1.25, 95%CI: 1.10-1.42) and third (HR=1.18, 95%CI: 1.03-1.34) trimesters. Negative associations were observed between ASD and 03 during the whole gestation period (increase HR=0.74, 95%CI: 0.56-0.97, per 10-ppb) and between ASD and PM10 during the whole gestation period (HR=0.90, 95%CI: 0.85-0.96, per 10-pg/m3) as well as in the second (HR=0.94, 95%CI: 0.90-0.99) and third (HR=0.91, 95%CI: 0.87-0.96) trimesters. The results suggested that air pollution during pregnancy may affect the development of the nervous system of the fetus and that ASD may be related to exposures to environmental pollutants.