Obesity, Physical Inactivity, and Colonic Diverticular Disease Requiring Hospitalization in Women: A Prospective Cohort Study

OBJECTIVES: Lifestyle factors other than dietary fiber intake and risk for colonic diverticular disease have only been examined in few studies. The objective of this study was to investigate the association between obesity and physical inactivity and diverticular disease in a population-based cohort of women. METHODS: This was a prospective population-based cohort study. In all, 36,592 women, born 1914-1948, in the Swedish Mammography Cohort were followed 1997-2009. Body mass index (BMI; kg/m(2)), physical activity, diet, smoking, and other lifestyle factors were collected at baseline through questionnaires. Cases of diverticular disease were identified from the Swedish Patient and Death Registers. Relative risks (RRs) of diverticular disease requiring hospitalization (or being the cause of death) according to BMI and physical activity were estimated using Cox proportional hazards models. The multivariable models were adjusted for age; intake of dietary fiber; diabetes; hypertension; use of acetylsalicylate acid, non-steroid anti-inflammatory drug, or steroid medication; alcohol consumption; smoking; and educational level. RESULTS: During 12 years, 626 cases of incident diverticular disease requiring hospitalization were found. Two women were registered in the National Death Register only. In multivariable analysis, women with BMI 25-29.99 had 29% increased risk (RR=1.29; 95% confidence interval (CI): 1.08, 1.54) and obese women (BMI >= 30) had 33% (1.33; 95% CI: 1.03-1.72) increased risk of diverticular disease compared to women with BMI 20-24.99. Exercise <= 30 min/day increased the risk for disease with 42% (1.42; 95% CI: 1.18-1.69) compared with exercise >30 min/day in multivariable analysis. Ninety-eight subjects were hospitalized due to complications; perforation or abscess. Women with BMI >= 30 had a twofold (RR=2.00; 95% CI: 1.08-3.73; P=0.028) increased risk for complicated disease. CONCLUSIONS: Overweight, obesity, and physical inactivity among women increase diverticular disease requiring hospitalization.