Recreational physical activity and risk of prostate cancer: A prospective population-based study in Norway (the HUNT study).

Physical activity has been studied in relation to prostate cancer risk, but the findings have been inconclusive. We prospectively examined the association between self-reported recreational physical activity and overall risk of prostate cancer, risk of advanced disease and risk of prostate cancer death in a cohort of 29,110 Norwegian men. Incident prostate cancers were obtained from the Norwegian Cancer Registry, and prostate cancer deaths were obtained from the national Cause of Death Registry. During 17 years of follow-up, 957 incident cases were identified, 266 of them were advanced (i.e. metastases at diagnosis) and 354 of the incident cases died from prostate cancer. In multivariable analysis, frequency and duration of exercise were inversely associated with the risk of advanced prostate cancer (p for trend = 0.04 and 0.02). We computed a summary score that combined frequency, duration and intensity of exercise, and this score showed inverse associations with advanced prostate cancer risk and mortality (p for trend = 0.02 and 0.07). Compared to men who reported no activity, the relative risks (95% confidence intervals) among men in the highest category of physical exercise was 0.64 (0.43-0.95) for advanced prostate cancer and 0.67 (0.48-0.94) for prostate cancer death. We found no association between physical activity and overall risk of prostate cancer. We conclude that recreational physical exercise is associated with reduced risk of advanced prostate cancer and prostate cancer death.