Physical activity is associated with reduced risk of liver disease in the prospective UK Biobank cohort

Abstract: Background and Aims Previous studies have identified physical activity as an important lifestyle factor in the pathogenesis of chronic liver diseases (CLD). However, most studies were short in follow-up, and based on self-reported activity. Moreover, it is unknown whether physical activity affects the risk of liver disease development in the general population. Here, we aimed to clarify the association between physical activity and CLD by examining the risk of liver disease and progression in relation to accelerometer-based physical activity in a large subset of prospectively recruited participants. Methods We analyzed data from 96,688 participants in the UK Biobank that recorded their physical activity through the use of a wrist accelerometer. Relative risks for development of liver diseases were calculated using multivariable-adjusted Cox regression models. In a subgroup of participants without any previously diagnosed liver disease (n=95,974), a total of 374 liver disease cases were diagnosed during follow-up (mean=5.5years). Results Participants in the top compared with the bottom quartile of physical activity had a reduced risk of both overall CLD (HR:0.41[0.29–0.59]) and NAFLD (HR:0.39[0.21–0.70]). An activity increase of an additional 2,500 steps per day, was associated with a 38% reduction in CLD and a 47% reduction in NAFLD development, independent of adiposity. In the subgroup of participants with previously diagnosed liver disease (n=714), participants in the top compared with the bottom quartile of physical activity had a striking 89% risk-reduction in liver-related death (HR:0.11[0.02-0.86]), and 85% risk-reduction in all-cause mortality (aHR:0.15[0.05-0.44]). Walking additional 2,500 steps per day was associated with 44% reduction in liver disease progression. Conclusions Greater physical activity is associated with a dose-dependent reduction in liver disease, which appears to be independent of adiposity.