Abstract 2829: Recreational physical activity and epithelial ovarian cancer risk in the California Teachers Study

Abstract

Abstract Background: It has been hypothesized that physical activity may reduce the risk of ovarian cancer by influencing sex hormones, body fat, and frequency of ovulation. However, epidemiologic studies have provided inconsistent results. Methods: We explored the association between recreational physical activity and epithelial ovarian cancer risk in 106,270 women ages 22 to 84 years old when they joined the prospective California Teachers Study in 1995-1996. Information on strenuous and moderate physical activities from high school through age 54 years or age at cohort entry if younger than 54, and sedentary behavior one year before cohort entry was collected by self-administered questionnaire. Follow-up through 2007 identified 431 women with incident invasive epithelial ovarian cancer. Multivariable adjusted Cox proportional hazards modeling was used to compute hazard rate ratios (RR) and 95% confidence intervals (CI). Results: Long-term recreational physical activity level was not associated with epithelial ovarian cancer risk, although a slightly lower risk was observed among women with high activity levels (average activity > 3 hrs/wk) (RR=0.81, 95%CI=0.61-1.08) relative to those with low activity levels (P for trend=0.20). Physical activity at different life periods, including the 3 years before cohort entry, also indicated a similar, statistically non-significant lower risk of epithelial ovarian cancer. No associations were observed for sedentary behavior one year before cohort entry. Conclusion: Overall, results from this study did not suggest a strong inverse association between recreational physical activity and epithelial ovarian cancer risk. Furthermore, sedentary behavior characterized by sitting time in the year prior to cohort entry was not a predictor of ovarian cancer risk. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2829.