Age-standardised burden of incident diabetes attributable to PM2·5 air pollution per 100 000 population (A) and age-standardised DALYs due to incident diabetes attributable to PM2·5 per 100 000 population (B) DALYs=disability-adjusted life-years. ATG=Antigua and Barbuda. VCT=Saint Vincent and the Grenadines. LCA=Saint Lucia. TTO=Trinidad and Tobago. Isl=Island. FSM=Federated States of Micronesia. TLS=Timor-Leste. Graphic: Bowe, et al., 2018 / The Lancet Planetary Health

By Laurel Hamers
9 July 2018
(Science News) – Air pollution caused 3.2 million new cases of diabetes worldwide in 2016, according to a new estimate.
Fine particulate matter, belched out by cars and factories and generated through chemical reactions in the atmosphere, hang around as haze and make air hard to breathe. Air pollution has been linked to chronic conditions such as heart disease and diabetes (SN: 9/30/17, p. 18), but this study is one of the first attempts to quantify the connection for diabetes. Researchers tracked 1.7 million U.S. veterans for almost a decade to assess their risk of developing diabetes. They also used data from global studies on diabetes risk, as well as air quality data from the U.S. Environmental Protection Agency and NASA, to create equations that analyzed the connection between air pollution exposure and diabetes globally.The new estimate, reported in July in The Lancet Planetary Health, holds air pollution responsible for about 14 percent of new cases of diabetes worldwide. Factors such as genetics, weight, activity level and diet also influence the risk of the disease, which is on the rise globally. (The World Health Organization estimates that 422 million people now live with type 2 diabetes — up from 108 million in 1980.)The burden isn’t the same around the globe: Unsurprisingly, countries with high pollution levels, such as Pakistan, India, and China, also have especially high rates of air pollution-linked diabetes. The United States, which now has comparatively clean air, is also high on the list.

Air pollution is triggering diabetes in 3.2 million people each year

ABSTRACT: We examined the relationship of PM2·5 and the risk of incident diabetes in a longitudinal cohort of 1 729 108 participants followed up for a median of 8·5 years (IQR 8·1–8·8). In adjusted models, a 10 μg/m3 increase in PM2·5 was associated with increased risk of diabetes (HR 1·15, 95% CI 1·08–1·22). PM2·5 was associated with increased risk of death as the positive outcome control (HR 1·08, 95% CI 1·03–1·13), but not with lower limb fracture as the negative outcome control (1·00, 0·91–1·09). An IQR increase (0·045 μg/m3) in ambient air sodium concentration as the negative exposure control exhibited no significant association with the risk of diabetes (HR 1·00, 95% CI 0·99–1·00). An integrated exposure response function showed that the risk of diabetes increased substantially above 2·4 μg/m3, and then exhibited a more moderate increase at concentrations above 10 μg/m3. Globally, ambient PM2·5 contributed to about 3·2 million (95% uncertainty interval [UI] 2·2–3·8) incident cases of diabetes, about 8·2 million (95% UI 5·8–11·0) DALYs caused by diabetes, and 206 105 (95% UI 153 408–259 119) deaths from diabetes attributable to PM2·5 exposure. The burden varied substantially among geographies and was more heavily skewed towards low-income and lower-to-middle-income countries. The global toll of diabetes attributable to PM2·5 air pollution is significant. Reduction in exposure will yield substantial health benefits.

The 2016 global and national burden of diabetes mellitus attributable to PM2·5 air pollution