Long-term sedentary work and the risk of subsite-specific colorectal cancer

Am J Epidemiol. 2011 May 15;173(10):1183-91. doi: 10.1093/aje/kwq513. Epub 2011 Mar 18.


Research suggests that sedentary behavior may increase the risk of some chronic diseases. The aims of the study were to examine whether sedentary work is associated with colorectal cancer and to determine whether the association differs by subsite. A total of 918 cases and 1,021 controls participated in a population-based case-control study of colorectal cancer in Western Australia in 2005-2007. Data were collected on lifestyle, physical activity, and lifetime job history. The estimated effects of sedentary work on the risk of cancers of the proximal colon, distal colon, and rectum were analyzed by using multinomial logistic regression. Compared with participants who did not spend any time in sedentary work, participants who spent 10 or more years in sedentary work had almost twice the risk of distal colon cancer (adjusted odds ratio = 1.94, 95% confidence interval: 1.28, 2.93) and a 44% increased risk of rectal cancer (adjusted odds ratio = 1.44, 95% confidence interval: 0.96, 2.18). This association was independent of recreational physical activity and was seen even among the most recreationally active participants. Sedentary work was not associated with the risk of proximal colon cancer. These results suggest that long-term sedentary work may increase the risk of distal colon cancer and rectal cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Body Mass Index
  • Case-Control Studies
  • Colonic Neoplasms / epidemiology
  • Colonic Neoplasms / etiology
  • Colorectal Neoplasms / epidemiology*
  • Colorectal Neoplasms / etiology
  • Confidence Intervals
  • Employment / statistics & numerical data
  • Female
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Motor Activity
  • Odds Ratio
  • Rectal Neoplasms / epidemiology
  • Rectal Neoplasms / etiology
  • Risk Factors
  • Sedentary Behavior*
  • Socioeconomic Factors
  • Surveys and Questionnaires
  • Time Factors
  • Western Australia / epidemiology