Women with type 1 diabetes have increased risk for poor obstetric outcomes. Prenatal air pollution exposure is also associated with adverse outcomes for women and infants. We examined whether women with type 1 diabetes are more vulnerable than other women to pollution-associated risks during pregnancy.
In singleton deliveries from the Consortium on Safe Labor (2002-2008), obstetric and neonatal outcomes were compared for women with type 1 diabetes (n=507) and women without autoimmune disease (n=204,384). Preconception, trimester, and whole pregnancy average air pollutant exposure (ozone (O3), carbon monoxide (CO), particulate matter >10 microns (PM10), PM >2.5 microns (PM2.5), sulfur dioxide (SO2), nitrogen oxides (NOx)) were estimated using modified Community Multiscale Air Quality models. Poisson regression models with diabetes*pollutant interaction terms estimated relative risks and 95% confidence intervals for adverse outcomes, adjusted for maternal characteristics and geographic region.
For whole pregnancy exposure to SO2, women with type 1 diabetes had 15% increased risk (RR:1.15 95%CI:1.01,1.31) and women without autoimmune disease had 5% increased risk (RR:1.05 95%CI:1.05,1.06) for small for gestational age birth (pinteraction=0.09). Additionally, whole pregnancy O3 exposure was associated with 10% increased risk (RR:1.10 95%CI:1.02,1.17) among women with type 1 diabetes and 2% increased risk (RR:1.02 95%CI:1.00,1.04) among women without autoimmune disease for perinatal mortality (pinteraction=0.08). Similar patterns were observed between PM2.5 exposure and spontaneous preterm birth.
Pregnant women with type 1 diabetes may be at greater risk for adverse outcomes when exposed to air pollution than women without autoimmune disease.
Williams, A. D., Kanner, J., Grantz, K. L., Ouidir, M., Sheehy, S., Sherman, S., Robledo, C., & Mendola, P. (2021). Air pollution exposure and risk of adverse obstetric and neonatal outcomes among women with type 1 diabetes. Environmental research, 197, 111152. https://doi.org/10.1016/j.envres.2021.111152