Long-term exposure to traffic-related air pollution and diabetes-associated mortality: a cohort study

• Published in: Diabetologia 2013-01, Vol.56 (1), p.36-46
• Main Authors: Raaschou-Nielsen, O., Sørensen, M., Ketzel, M., Hertel, O., Loft, S., Tjønneland, A., Overvad, K., Andersen, Z. J.
• Format: Article
• Language: English
• Subjects: Air Pollutants - toxicity; Air pollution; Biological and medical sciences; Cohort Studies; Confounding Factors (Epidemiology); Denmark - epidemiology; Diabetes Mellitus - epidemiology; Diabetes Mellitus - mortality; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Environmental Exposure - adverse effects; Epidemiology; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; Follow-Up Studies; Human Physiology; Humans; Insulin resistance; Internal Medicine; Male; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Middle Aged; Mortality; Nitrogen Dioxide - toxicity; Outdoor air quality; Proportional Hazards Models; Prospective Studies; Registries; Residence Characteristics; Surveys and Questionnaires; Time Factors; Urban Health; Vehicle Emissions - toxicity
• ISSN: 0012-186X; 1432-0428
• DOI: 10.1007/s00125-012-2698-7

Aims/hypothesis The aim of this study was to investigate whether air pollution from traffic at a residence is associated with mortality related to type 1 or type 2 diabetes. Methods We followed up 52,061 participants in the Danish Diet, Cancer and Health cohort for diabetes-related mortality in the nationwide Register of Causes of Death, from baseline in 1993–1997 up to the end of 2009, and traced their residential addresses since 1971 in the Central Population Registry. We used dispersion-modelled concentration of nitrogen dioxide (NO 2 ) since 1971 and amount of traffic at the baseline residence as indicators of traffic-related air pollution and used Cox regression models to estimate mortality-rate ratios (MRRs) with adjustment for potential confounders. Results Mean levels of NO 2 at the residence since 1971 were significantly associated with mortality from diabetes. Exposure above 19.4 μg/m 3 (upper quartile) was associated with a MRR of 2.15 (95% CI 1.21, 3.83) when compared with below 13.6 μg/m 3 (lower quartile), corresponding to an MRR of 1.31 (95% CI 0.98, 1.76) per 10 μg/m 3 NO 2 after adjustment for potential confounders. Conclusions/interpretation This study suggests that traffic-related air pollution is associated with mortality from diabetes. If confirmed, reduction in population exposure to traffic-related air pollution could be an additional strategy against the global public health burden of diabetes.