Patterns and predictors of mortality and disease progression among patients with non-alcoholic fatty liver disease

Background Factors associated with mortality and disease progression in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are poorly understood. Aims To assess the impact of liver disease severity, demographics and comorbidities on all-cause mortality and liver disease progression in a large, real-world cohort of German NAFLD patients. Methods Claims data from the German Institut fur angewandte Gesundheitsforschung database between 2011 and 2016 were analyzed retrospectively. Adult patients diagnosed with NAFLD and/or NASH were categorised as NAFLD, NAFLD non-progressors, compensated cirrhosis, decompensated cirrhosis, liver transplant or hepatocellular carcinoma (HCC). The longitudinal probability of mortality and incidence of progression were calculated for disease severity cohorts and multivariable analyses performed for adjusted mortality. Results Among 4 580 434 patients in the database, prevalence of NAFLD was 4.7% (n = 215 655). Of them, 36.8% were non-progressors, 0.2% compensated cirrhosis, 9.6% decompensated cirrhosis, 0.0005% liver transplant and 0.2% HCC. Comorbidity rates were significantly higher in compensated cirrhosis, decompensated cirrhosis and HCC compared with non-progressors. The longitudinal probability of mortality for non-progressors, compensated cirrhosis, decompensated cirrhosis and HCC was 3.6%, 18.7%, 28.8% and 68%, respectively. Independent predictors of mortality included cardiovascular disease, type 2 diabetes mellitus, hypertension, obesity and renal impairment. The cumulative incidence of progression in NAFLD and compensated cirrhosis patients was 10.7% and 16.7%, respectively, over 5 years of follow-up. Conclusion NAFLD patients were severely under-diagnosed and had a high probability of mortality that increased with disease progression. Early identification and effective management to halt or reverse fibrosis are essential to prevent progression.