Physical activity, sedentary behavior, and the risk of colon and rectal cancer in the NIH-AARP Diet and Health Study
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In order to prospectively investigate physical activity at varying intensities and sedentary behavior in relation to colorectal cancer.
We considered 488,720 participants of the NIH-AARP Diet and Health Study who were aged 50–71 years at baseline in 1995–1996. Through 31 December, 2003, we identified 3,240 and 1,482 colorectal cancers among men and women, respectively. We estimated multivariable relative risks (RR) and 95% confidence intervals (CI) of colorectal cancer using Cox regression.
Engaging in exercise/sports five or more times per week compared to never or rarely exercising was associated with a reduced risk of colon cancer among men (p = 0.001; RR = 0.79, 95% CI = 0.68–0.91) and a suggestive decrease in risk among women (p = 0.376; RR = 0.85, 95% CI = 0.70–1.04). Engaging in exercise/sports was also associated with a decreased risk of rectal cancer in men (P = 0.074; RR comparing extreme categories = 0.76, 95% CI = 0.61–0.94). In men, we observed inverse relations of both low intensity (p = 0.017; RR = 0.81, 95% CI = 0.65–1.00 for ≥7 h/week) and moderate to vigorous intensity activity (p = 0.037; RR = 0.82, 95% CI = 0.67–0.99 for ≥7 h/week) to colon cancer risk. In contrast, sedentary behavior (time spent watching television/videos) was positively associated with colon cancer (p < 0.001; RR = 1.61, 95% CI = 1.14–2.27 for ≥9 h/day) among men. Similar, but less pronounced relations were observed in women.
Engaging in physical activity of any intensity is associated with reductions in colon and rectal cancer risk. Conversely, time spent sedentary is associated with increased colon cancer risk.
KeywordsColon cancer Rectal cancer Physical activity Cohort studies
- 1.American Cancer Society (2007) Cancer facts and figures 2007. American Cancer Society, Atlanta, GAGoogle Scholar
- 16.Chao A, Connell CJ, Jacobs EJ et al (2004) Amount, type, and timing of recreational physical activity in relation to colon and rectal cancer in older adults: the Cancer Prevention Study II Nutrition Cohort. Cancer Epidemiol Biomarkers Prev 3:2187–2195Google Scholar
- 42.Michaud DS, Midthune D, Hermansen S et al (2005) Comparison of cancer registry case ascertainment with SEER estimates and self-reporting in a subset of the NIH-AARP Diet and Health Study. J Regist Manag 32:70–75Google Scholar
- 46.Schor JB (1992) The overworked American. Harper Collins, New YorkGoogle Scholar
- 48.Gerhardsson de Verdier M, Norell SE, Kiviranta H, Pedersen NL, Ahlbom A (1986) Sedentary jobs and colon cancer. Am J Epidemiol 123:775–780Google Scholar