Prenatal exposure to ambient air pollution and the risk of type 1 diabetes in the offspring: a nationwide Danish study

The etiology of type 1 diabetes (T1DM) is not fully understood, but a complex interplay of genetic and environmental factors is involved. Exposure to ambient air pollution during pregnancy has been suggested as a risk factor of T1DM. This study aimed to examine whether accumulated prenatal exposure to ambient air pollution is associated with increased risk of T1DM in offspring. We performed a national register-based cohort study using the Danish DOC*X-Generation cohort, including female workers and their offspring. Residential air pollution concentrations during pregnancy were estimated using an air pollution modeling system and included particulate matter smaller than 2.5 m, elemental carbon, nitrogen dioxide, and ozone. The cohort was linked to the Danish National Patient Register to determine the incidence of T1DM in offspring. We used Poisson regression model to calculate adjusted incidence rate ratios (IRR) and 95% confidence intervals (CI). μ The study population consisted of 1,233,476 female workers, where 0.31% (n = 3848) developed T1DM. The results did not indicate association between maternal exposure to air pollutants in pregnancy and T1DM development in the offspring. When stratifying by offspring sex, ozone seemed associated to increase risk for T1DM in girls (IRR = 1.13, 95%CI: 0.99-1.29) and this was [...]