Diabetes Incidence and Long-Term Exposure to Air Pollution

Abstract

OBJECTIVEdAnimal and cross-sectional epidemiological studies suggest a link between air pollution and diabetes, whereas the limited prospective data show mixed results. We studied the association between long-term exposure to traffic-related air pollution and incidence of diabetes.RESEARCH DESIGN AND METHODSdWe followed 57,053 participants of the Danish Diet, Cancer, and Health cohort in the Danish National Diabetes Register between baseline (1993-1997) and 27 June 2006. We estimated the mean levels of nitrogen dioxide (NO 2 ) at the residential addresses of the cohort participants since 1971 and modeled the association between NO 2 and diabetes incidence with a Cox regression model, separately for two definitions of diabetes: all cases and a more strict definition where unconfirmed cases were excluded.RESULTSdOver a mean follow-up of 9.7 years of 51,818 eligible subjects, there were 4,040 (7.8%) incident diabetes cases in total and 2,877 (5.5%) with confirmed diagnoses. Air pollution was not associated with all diabetes cases (hazard ratio 1.00 [95% CI 0.97-1.04] per interquartile range of 4.9 mg/m 3 mean NO 2 levels since 1971), but a borderline statistically significant association was detected with confirmed cases of diabetes (1.04 [1.00-1.08]). Among confirmed diabetes cases, effects were significantly enhanced in nonsmokers (1.12 [1.05-1.20]) and physically active people (1.10 [1.03-1.16]).CONCLUSIONSdLong-term exposure to traffic-related air pollution may contribute to the development of diabetes, especially in individuals with a healthy lifestyle, nonsmokers, and physically active individuals. 35:92-98, 2012 Diabetes Care

MECHANISMS IN ENDOCRINOLOGY: Effect of long-term exposure to air pollution on type 2 diabetes mellitus risk: a systemic review and meta-analysis of cohort studies

“…One article reported two individual cohort studies, and was extracted as two individual studies (14). Thus, ten prospective cohort studies from nine articles were finally included into the meta-analysis (10,11,12,13,14,20,21,22,23). Table 1 shows the main characteristics of those ten cohort studies included in the meta-analysis (Table 1).…”

“…Table 1 shows the main characteristics of those ten cohort studies included in the meta-analysis (Table 1). Those ten cohort studies involved a total of 2 371 907 participants and 21 095 incident cases of type 2 diabetes (10,11,12,13,14,20,21,22,23). Among those ten cohort studies, nine studies reported incident new cases of type 2 diabetes (10,11,13,14,20,21,22,23), while the left one reported events of deaths coded as diabetes (12).…”

“…Those ten cohort studies involved a total of 2 371 907 participants and 21 095 incident cases of type 2 diabetes (10,11,12,13,14,20,21,22,23). Among those ten cohort studies, nine studies reported incident new cases of type 2 diabetes (10,11,13,14,20,21,22,23), while the left one reported events of deaths coded as diabetes (12). There were three studies from USA (10,14), three studies from Canada (12,13,20), two studies from Germany (21,22), one from Denmark (11), and one from Switzerland (24) ( Table 1).…”

“…However, the effect of air pollution on type 2 diabetes risk has not been clearly described. Several studies have assessed the association between long-term exposure to air pollution and risk of type 2 diabetes, but the association remains unclear owing to the conflicting results (10,11,12,13,14). To assess the effect of long-term exposure to air pollution on type 2 diabetes risk, a meta-analysis of prospective cohort studies was performed according to the standard guideline for conducting and reporting meta-analyses of observational studies.…”

Estimating the global abundance of ground level presence of particulate matter (PM2.5)

“…2009; Farhat et al, 2011), central nervous system disorders (Sunderman, 2001;Kreyling et al, 2006;Block and Calderon-Garciduenas, 2009;Pearson et al, 2010;Wang et al, 2012) and diabetes (Andersen, 2012;Andersen et al, 2012). Since many of these health conditions are interlinked, comprehensive studies are required to better understand the impact of PM 2.5 .…”