E-POSTER GALLERY (ID 409)

P-0236 - Early life exposure to fine particulate matter and childhood asthma in Beijing, China: A case-control study

Abstract Control Number
1773
Abstract Body
Background: Previous studies indicated that the effect of early life exposure to ambient air pollution on childhood asthma is still unclear. Methods: A case-control study for children in 2010 was performed in Beijing. A spatio-temporal model was developed using PM2.5 (particles with an aerodynamic diameter of less than 2.5 μm) data from 35 monitoring stations and the geographic information data from 2013, which was time-adjusted and then be applied to estimate the personal exposure level in 2004-2010. Logistic regression model was used to examine the effects of PM2.5 exposure during different pre-natal (the first trimester, second trimester, third trimester and whole pregnancy) and post-natal periods (the first year after birth) on childhood asthma.Results: In total, 118 cases (mean:4.5 ys) and 133 healthy controls (mean:4.3 ys) were included in this study. The PM2.5 exposure level of asthma cases ranged from 74.4 to 233.0 μg /m3 in different time windows of early life. The level of PM2.5 in the case group was higher than that in the control group (P<0.05). The exposure to PM2.5 during the whole pregnancy had an effect on asthma in the preschool children, with OR of 1.77 (95% CI: 1.33-2.36) for per 10 μg/m3 increase in PM2.5. The sensitive exposure window during pregnancy was the second trimester, with OR of 1.25 (95% CI: 1.10-1.41) for per 10 μg/m3 increase in PM2.5. PM2.5 exposure in the first year after birth also had an effect on asthma in the preschool children, with OR of 1.34 (95% CI: 1.07-1.68), and the risk was higher than that in the sensitive window of pregnancy. Conclusions: Exposures to PM2.5 during pregnancy and the first year of life were associated with the increased risk of asthma and there appeared to be stronger effects on asthma in the second trimester and the first year after birth.