TY - JOUR T1 - Body size and physical activity in relation to incidence of chronic obstructive pulmonary disease JF - Canadian Medical Association Journal JO - CMAJ DO - 10.1503/cmaj.140025 SP - cmaj.140025 AU - Gundula Behrens AU - Charles E. Matthews AU - Steven C. Moore AU - Albert R. Hollenbeck AU - Michael F. Leitzmann Y1 - 2014/01/01 UR - http://www.cmaj.ca/content/early/2014/07/07/cmaj.140025.abstract N2 - Background: Limited evidence suggests that adiposity and lack of physical activity may increase the risk of chronic obstructive pulmonary disease (COPD). We investigated the relation of body size and physical activity with incidence of COPD. Methods: We obtained data on anthropometric measurements and physical activity from 113 279 participants in the National Institutes of Health–AARP Diet and Health Study who reported no diagnosis of COPD at baseline (1995–1996). We estimated associations between these measurements and subsequent diagnosis of COPD between 1996 and 2006, with extensive adjustment for smoking and other potentially confounding variables. Results: Participants reported 3648 new COPD diagnoses during follow-up. The incidence of COPD was higher in both severely obese (BMI ≥ 35) and underweight (BMI < 18.5) participants, but after adjustment for waist circumference, only underweight remained positively associated with COPD (RR 1.56, 95% CI 1.15–2.11). Larger waist circumference (highest v. normal categories, RR 1.72, 95% CI 1.37–2.16) and higher waist–hip ratio (highest v. normal categories, RR 1.46, 95% CI 1.23–1.73) were also positively associated with COPD. In contrast, hip circumference (highest v. normal categories, RR 0.78, 95% CI 0.62–0.98) and physical activity (≥ 5 v. 0 times/wk, RR 0.71, 95% CI 0.63–0.79) were inversely associated with COPD. Interpretation: Obesity, in particular abdominal adiposity, was associated with an in creased risk of COPD, and increased hip circumference and physical activity were associated with a decreased risk of COPD. These findings suggest that following guidelines for a healthy body weight, body shape and physical activity decrease the risk of COPD. ER -