Perinatal Exposure to Ambient Air Pollution and Greenness, and the Incidence of Paediatric Diabetes: A Population-Based Cohort Study

摘要

Background: Ambient air pollution exposure during early life has recently been associated with diabetes incidence in children. However, little is known regarding critical exposure windows and if exposure to greenness could modify these associations. This study sought to assess the relationship between selected air pollutants (NO2, PM2.5, O3, and Ox [oxidant capacity]) and the incidence of paediatric diabetes. Methods: Our cohort consisted of 754,698 mother-infant pairs occurring between 2006 and 2012 in the province of Ontario, Canada. Diabetes incidence was ascertained using population-based health administrative data with a validated algorithm. The cohort was followed until 2015. Temporally adjusted exposure to NO2, PM2.5, and O3 was estimated using satellite-based regression, land-use regression, and a fusion-based approach, respectively, and was assigned to subjects' residential postal codes during pregnancy. Ox was calculated as the redox-weighted average of O3 and NO2. Satellite-derived normalized difference vegetation index (NDVI) was used to represent the amount of green vegetation at a 250m buffer across Ontario. Associations between total pregnancy, trimester specific, and early life exposures to ambient air pollutants and childhood diabetes incidence up to age 6 were estimated using Cox regression models. Results: 1,094 children with diabetes were identified. Each IQR increase in 03 and Ox exposures in the second trimester of pregnancy were associated with hazard ratios of 1.36 (95% CI: 1.07-1.73) and 1.45 (95% CI: 1.05-1.81), respectively. These relationships exhibited linear shapes, and exposure to greenness was found to have a protective modifying effect (p-interaction < 0.04). There were no other positive associations observed for other pollutants and other time periods. Conclusions: Air pollution, especially O3 and Ox, was linked to increased diabetes risk in children. Exposure to greenness during pregnancy appeared to attenuate these associations.