Physical Activity, Fatty Liver, and Glucose Metabolism Over the Life Course: The Lifelines Cohort

We examined the dose-dependent association of habitual moderate-to-vigorous physical activity (MVPA) with the biochemical markers for nonalcoholic fatty liver disease (NAFLD) and whether this association changes with age and degree of impaired glucose metabolism. We also investigated whether the associations depend on the domain of MVPA.

In this study, using data from the population-based Lifelines cohort (N = 42,661), MVPA was self-reported on the short questionnaire to assess health-enhancing physical activity. NAFLD was defined as a fatty liver index value of >60, based on body mass index, waist circumference, plasma triglycerides, and gamma-glutamyltransferase. Glucose metabolism was defined as normal (NGM), impaired (IGM), and type 2 diabetes mellitus (T2DM). Exclusion criteria were previously diagnosed hepatitis or cirrhosis and excessive alcohol use. All analyses were adjusted for age, sex, and education.

Higher MVPA was dose dependently associated with a lower risk of having NAFLD: compared with "No MVPA," the odds ratios (ORs) (95% confidence intervals) for MVPA quintiles were 0.78 (0.71-0.86), 0.64 (0.58-0.70), 0.53 (0.48-0.59), 0.51 (0.46-0.56), and 0.45 (0.41-0.50) for the highest level of MVPA. The association between MVPA and NAFLD was stronger for more impaired glucose status (ORNGM = 0.49 (0.42-0.57), ORIGM = 0.46 (0.40-0.54), ORT2DM = 0.42 (0.27-0.66)) and for older age (OR20-40 years = 0.51 (0.42-0.62), OR60-80 years = 0.37 (0.29-0.48)) with the highest level of MVPA, relative to No MVPA. No favorable association was observed for occupational MVPA. With regard to MVPA and fibrosis, associations with fibrosis markers showed contradictory results.

Higher MVPA levels are dose dependently associated with a lower NAFLD risk. This association is stronger in people with diabetes and older adults.