title: Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study.
abstract: Sedentary behavior (sitting time) has been proposed as an independent risk factor for some cancers; however, its role in the development of prostate cancer has not been determined. We examined the prospective associations of self-reported daily sitting time and daily television/video viewing time with the risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated HRs and 95% confidence intervals (CI) using Cox proportional hazards regression. Between 1996 and 2006, there were 13,751 incident (including 1,365 advanced) prostate cancer cases identified; prostate cancer mortality (through 2008) was 669. No strong or significant association with prostate cancer risk was seen in fully adjusted models for either daily sitting or television/video time. There were some suggestions of effect modification by body mass index (BMI; interaction for television/video time and BMI, P = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but nonsignificant, increase amongst obese men (HR = 1.28; 95% CI, 0.98-1.69); a null association was observed amongst overweight men (HR = 1.04; 0.89-1.22); and, for men with a normal BMI, television/video time was associated with a nonsignificant risk decrease (HR = 0.82; 95% CI, 0.66-1.01). Similar patterns were observed for total daily sitting and television/video time in advanced prostate cancer and prostate cancer mortality. Sedentary behavior seems to play a limited role in the development of prostate cancer; however, we cannot rule out potential effect modification by BMI or the impact of measurement error on results.
authors: Authors' Affiliations: Physical Activity Laboratory, Baker IDI Heart and Diabetes Institute; Melbourne School of Population and Global Health, Faculty of Medicine, Dentistry, and Health Sciences, The University of Melbourne, Melbourne, Australia; Department of Population Health Research, Alberta Health Services-CancerControl; Departments of Oncology, Community Health Sciences, and Mathematics and Statistics, University of Calgary, Calgary, Canada; AARP, Washington, DC; and Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland.
authors: Brigid M
authors: BM
authors: Lynch
authors: Christine M
authors: CM
authors: Friedenreich
authors: Karen A
authors: KA
authors: Kopciuk
authors: Albert R
authors: AR
authors: Hollenbeck
authors: Steven C
authors: SC
authors: Moore
authors: Charles E
authors: CE
authors: Matthews
mesh_terms: D000368:Aged; D015992:Body Mass Index; D004032:Diet; D015444:Exercise; D005247:Feeding Behavior; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology; D011379:Prognosis; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000209:etiology* / Q000401:mortality; D012307:Risk Factors; D057185:Sedentary Behavior; D057566:Self Report; D011795:Surveys and Questionnaires; D015996:Survival Rate