Occupational exposure to dusts, gases and fumes and incidence of chronic obstructive pulmonary disease in the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults

RATIONALE: There is limited evidence from population-based studies demonstrating incidence of spirometric-defined chronic obstructive pulmonary disease (COPD) in association with occupational exposures. OBJECTIVES: We evaluated the association between occupational exposures and incidence of COPD in the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA). MEASUREMENTS AND MAIN RESULTS: Pre-bronchodilator ratio of forced expiratory volume in one second over forced vital capacity (FEV(1)/FVC) was measured in 4,267 non-asthmatic SAPALDIA participants ages 18-62 at baseline in 1991 and at follow-up in 2001-2003. COPD was defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criterion (FEV(1)/FVC<0.70) and Quanjer reference equation (FEV(1)/FVC/=80% and <80% predicted FEV(1) for stage I and stage II+, respectively). Using the ALOHA job-exposure matrix, self-reported occupations at baseline were assigned exposures to biological dusts, mineral dusts, gases/fumes, and vapors, gases, dusts or fumes (high, low, unexposed as reference). Adjusted incident rate ratios (IRRs) of Stage I and Stage II+ COPD were estimated for each exposure in mixed Poisson regression models. Statistically significant (p<0.05) IRRs of stage II+ GOLD and LLN-COPD, indicating risks between two and five-fold, were observed for all occupational exposures at high levels. Occupational exposure-associated risk of stage II+ COPD was observed mainly in males, ages' >/=40 years, and remained elevated when restricted to non-smokers. CONCLUSIONS: In a Swiss working adult population, occupational exposures to biological dusts, mineral dusts, gases/fumes, and VGDF were associated with incidence of COPD of at least moderate severity