Physical activity and risk of renal cell carcinoma

The role of physical activity in the development of renal cell carcinoma was examined using a population-based case-control study conducted in the province of Ontario. Physical activity was examined in several ways, including by intensity and during various life periods. Frequency-matching by 5-year age groups and sex produced sets of 486 females (133 cases and 353 controls) and 447 males (172 cases, 275 controls). Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). After adjusting for age, body mass index and smoking, women who performed relatively high amounts of recent recreational activity (OR = 0.41, 95% CI 0.21-0.82 for the highest vs. lowest quartile of activity, 2 years ago), as well as strenuous recreational activity (OR = 0.40, 95% CI 0.22-0.75), had a reduced risk of developing the disease. In general, moderate recreational activity did not appear to be associated with risk in females. In males, a relatively high frequency of total and moderate recreational activity was associated with reduced risk (total, OR = 0.49, 95% CI 0.27-0.87; moderate, OR = 0.49, 95% CI 0.27-0.89), especially during the teen years. Recreational activity during one's 30s was not associated with cancer risk. There was also no association between occupational activity and cancer risk in females or males. The results of our study, in general, suggest that physical activity may be associated with a decreased risk of developing renal cell carcinoma. (C) 2003 Wiley-Liss, Inc.