Physical Activity and Pancreatic Cancer Risk among Urban Chinese: Results from Two Prospective Cohort Studies.

Background: Associations between physical activity and pancreatic cancer risk are unclear.
Methods: In two prospective cohort studies, the Shanghai Women's Health Study and Shanghai Men's Health Study, physical activity and other information were collected at the baseline interview of 72,451 women and 60,037 men. Participants were followed up through annual linkage with a cancer registry in combination with in-person interviews taking place every 2 to 4 years.
Results: We identified 225 female and 159 male cases during a median follow up of 16.1 and 10.3 years, respectively. Adult exercise participation was significantly associated with a decreased pancreatic cancer risk in men [hazard ratio (HR), 95% confidence interval (CI): 0.71 (0.50-1.00)]. Meeting the recommended minimum exercise threshold to achieve health benefits of 150 min/week of moderate-intensity or 75 min/week of vigorous-intensity exercise was associated with further decreased pancreatic cancer risk [HR (95% CI): 0.59 (0.40-0.87)]. We also observed an inverse association between adolescent physical activity and pancreatic cancer risk in men [HR (95% CI): 0.54 (0.33-0.90)]. Exercise throughout one's lifetime was associated with a 68% decrease in pancreatic cancer risk [HR (95% CI): 0.32 (0.16-0.66)]. No significant association was found in women. Adult non-exercise daily activity and occupational activity were not associated with pancreatic cancer risk in either men or women.Conclusions: Adult exercise and adolescent physical activity were significantly associated with a decreased pancreatic cancer risk in men but not in women.Impact: These findings underscore the importance of investigating the possible modification by sex on the exercise and pancreatic cancer risk association. Cancer Epidemiol Biomarkers Prev; 27(4); 479-87. ©2018 AACR. ©2018 American Association for Cancer Research.