title: Physical activity, occupational sitting time, and colorectal cancer risk in the Netherlands cohort study.
abstract: We investigated occupational energy expenditure and sitting time in the longest held job (in men only), nonoccupational physical activity, and former sports participation in relation to colorectal cancer endpoints. The Netherlands Cohort Study includes 120,852 participants who completed a self-administered questionnaire in 1986 when they were aged 55-69 years. By 2002, 1,819 male and 1,366 female colorectal cancer cases were available for case-cohort analyses. In men, higher occupational energy expenditure levels and fewer occupational sitting hours were associated with decreased hazard ratios for colon cancer, particularly distal colon cancer (occupational energy expenditure of ≥12 vs. <8 kJ/minute, hazard ratio (HR) = 0.71, 95% confidence interval (CI): 0.52, 0.97; P for trend = 0.01; occupational sitting hours of <2 vs. 6-8 hours/day, HR = 0.63, 95% CI: 0.48, 0.83; P for trend = 0.001). The median duration of the longest held job for male subcohort members was 29 years. Nonoccupational physical activity was inconsistently associated with colorectal cancer endpoints in men, and it was inversely associated with colon cancer in women, particularly distal colon cancer (>90 vs. ≤30 minutes/day, HR = 0.69, 95% CI: 0.50, 0.96; P for trend = 0.06), and rectal cancer (>90 vs. ≤30 minutes/day, HR = 0.59, 95% CI: 0.39, 0.90; P for trend = 0.02). In conclusion, regular long-term physical activity and fewer sitting hours may protect against colon cancer, particularly distal colon cancer; results for rectal cancer were mixed.
authors: Department of Epidemiology, Faculty of Health, Medicine, and Life Sciences, Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands. colinda.simons@maastrichtuniversity.nl
authors: Colinda C J M
authors: CC
authors: Simons
authors: Laura A E
authors: LA
authors: Hughes
authors: Manon
authors: M
authors: van Engeland
authors: R Alexandra
authors: RA
authors: Goldbohm
authors: Piet A
authors: PA
authors: van den Brandt
authors: Matty P
authors: MP
authors: Weijenberg
mesh_terms: D000368:Aged; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D004034:Diet Surveys; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009426:Netherlands / Q000453:epidemiology; D016016:Proportional Hazards Models; D012307:Risk Factors; D057185:Sedentary Behavior; D013177:Sports; D011795:Surveys and Questionnaires