Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study
A partir des données de la cohorte "NIH-AARP Diet and Health Study" portant sur 170 481 hommes, cette étude prospective évalue l'association entre un comportement sédentaire, le temps passé quotidiennement en position assise et le risque de cancer de la prostate
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 risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated hazard ratios and 95% confidence intervals 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 was some suggestion of effect modification by body mass index (interaction for television/video time and body mass index, p = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but non-significant increased 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 body mass index, television/video time was associated with a non-significant 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 appears to play a limited role in the development of prostate cancer, however we cannot rule out potential effect modification by body mass index or the impact of measurement error on results.