Associations between physical activity and risk of liver cancer: results from a population-based cohort study in Chinese women

Aims: Epidemiological evidence has revealed varying degrees of relationship between physical activity and risk of most cancers, but the association between physical activity and risk for primary liver cancer in Chinese has seldom been reported. This study aims to characterize the associations between different physical activity types and liver cancer risk in Chinese women. Methods: We collected physical activity information through the physical activity questionnaire (PAQ) and assigned a corresponding metabolic equivalent value according to the physical activity compendium. Multivariable-adjusted Cox regression models were utilized to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the relationships between physical activity and liver cancer. Results: A total of 72,674 females were enrolled in the cohort, with a median follow-up time of 18.12 years. By the end of 2016, 255 females were identified as incident cases of liver cancer. In Multivariable-adjusted Cox regression analysis, total physical activity (TPA), daily living physical activity (DPA) and leisure-time physical activity (LTPA) were not associated with the liver cancer risk in women. The highest tertile vs. none of HRs ( 95%CIs) were 0.82 (0.58, 1.17) for TPA, 0.80 (0.56, 1.15) for DPA, and 1.15 (0.82, 1.61) for adult LTPA in terms of measures as the METs-hour/week. For each activity, we found that the HRs (95%CIs) were 0.77 (0.55, 1.08) for stair climbing and 0.78 (0.53, 1.15) for participation in housework after further adjusting for body mass index and type 2 diabetes. Conclusion: Null significant results were found in the association between physical activity and female liver cancer risk in China.