Improvement of Nonalcoholic Fatty Liver Disease Reduces the Risk of Type 2 Diabetes Mellitus

Background/Aims: Little evidence is available about the effect of change in nonalcoholic fatty liver disease (NAFLD) status on risk of diabetes mellitus (DM) development. In this study, we tried to analyze the DM risk according to change in NAFLD status over time. Methods: Among a total of 10,141 individuals for whom routine healthcare assessment was performed, 2,726 subjects were selected according to the inclusion/exclusion criteria. NAFLD status change was determined by using serial abdominal ultrasonography and fatty liver index (FLI) during the follow-up period. Results: Subjects were categorized according to change in NAFLD status as follows: 670 subjects in the persistent NAFLD group, 155 subjects in the resolved NAFLD group, 498 subjects in the incident NAFLD group, and 1,403 subjects in the no NAFLD group. Multivariate Cox regression analysis revealed that incident NAFLD (hazard ratio [HR], 1.94; 95% confidence interval [CI], 1.08 to 3.50; p=0.026) and persistent NAFLD (HR, 3.59; 95% CI, 2.05 to 6.27; p<0.001) were independent risk factors for predicting DM development, whereas the risk with resolved NAFLD was not significantly different from that with no NAFLD. FLI could reproduce the results acquired by ultrasonography. Conclusions: This study demonstrated that future DM risk could be influenced by changes in NAFLD status over time. Resolution of NAFLD could reduce the risk of future DM development, while the development of new NAFLD could increase the risk of DM development.