Air Pollution and Mortality in Seven Million Adults: The Dutch Environmental Longitudinal Study (DUELS)

BACKGROUND: Long-term exposure to air pollution has been associated with mortality in urban cohort studies. Few studies have investigated this association in large-scale population registries, including non-urban populations. OBJECTIVES: The aim of the study was to evaluate the associations between long-term exposure to air pollution and nonaccidental and cause-specific mortality in the Netherlands based on existing national databases. METHODS: We used existing Dutch national databases on mortality, individual characteristics, residence history, neighborhood characteristics, and national air pollution maps based on land use regression (LUR) techniques for particulates with an aerodynamic diameter ≤ 10 μm (PM(10)) and nitrogen dioxide (NO(2)). Using these databases, we established a cohort of 7.1 million individuals ≥ 30 years of age. We followed the cohort for 7 years (2004–2011). We applied Cox proportional hazard models adjusting for potential individual and area-specific confounders. RESULTS: After adjustment for individual and area-specific confounders, for each 10-μg/m(3) increase, PM(10) and NO(2) were associated with nonaccidental mortality [hazard ratio (HR) = 1.08; 95% CI: 1.07, 1.09 and HR = 1.03; 95% CI: 1.02, 1.03, respectively], respiratory mortality (HR = 1.13; 95% CI: 1.10, 1.17 and HR = 1.02; 95% CI: 1.01, 1.03, respectively), and lung cancer mortality (HR = 1.26; 95% CI: 1.21, 1.30 and HR = 1.10 95% CI: 1.09, 1.11, respectively). Furthermore, PM(10) was associated with circulatory disease mortality (HR = 1.06; 95% CI: 1.04, 1.08), but NO(2) was not (HR = 1.00; 95% CI: 0.99, 1.01). PM(10) associations were robust to adjustment for NO(2); NO(2) associations remained for nonaccidental mortality and lung cancer mortality after adjustment for PM(10). CONCLUSIONS: Long-term exposure to PM(10) and NO(2) was associated with nonaccidental and cause-specific mortality in the Dutch population of ≥ 30 years of age. CITATION: Fischer PH, Marra M, Ameling CB, Hoek G, Beelen R, de Hoogh K, Breugelmans O, Kruize H, Janssen NA, Houthuijs D. 2015. Air pollution and mortality in seven million adults: the Dutch Environmental Longitudinal Study (DUELS). Environ Health Perspect 123:697–704; http://dx.doi.org/10.1289/ehp.1408254