Overweight, obesity and risk of work disability: a cohort study of construction workers in Germany

Objectives: Although obesity and permanent work disability impose a great burden on the individual and are very costly for society, data on the impact of being overweight on occupational disability are sparse, especially in men who work hard physically. The aim of this study was to investigate the association of body mass index (BMI) with work disability among construction workers. Methods: The association between BMI and work disability was examined during a mean follow-up period of 10.8 years in a cohort of 16 875 male construction workers in Wurttemberg, Germany, who participated in routine occupational health examinations from 1986 to 1992. Hazard ratios were calculated with normal weight (20.0-22.4 kg/m(2)) as reference using the Cox proportional hazards model, after adjustment for potential confounding factors. Results: Overall, a U-shaped association of BMI with all-cause work disability (total number = 3064 cases) was observed, with the lowest risk of disabilities at BMI levels between 25 and 27.4 kg/m(2). Strong positive associations were observed between BMI and work disability due to osteoarthritis or cardiovascular diseases, whereas BMI was inversely related to work disability due to cancer, even after exclusion of the first 3 years of follow-up. Conclusions: Moderate overweight is not associated with increased risk of work disability among construction workers, but obesity increases the risk of work disability due to osteoarthritis and cardiovascular disease.