Characterising Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis Patients in Secondary Care in England

OBJECTIVES: To characterise non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) patients receiving routine care in hospitals in England and to assess the incidence and describe the survival of key clinical outcomes (overall survival, liver failure, hepatocellular carcinoma (HCC), major adverse cardiovascular events (MACE)).

METHODS: This retrospective study used de-identified electronic health records from the Arcturis UK Dataset between 1 January 2015 and 5 April 2024. The demographic and clinical characteristics of NASH/NAFLD patients including comorbidities, laboratory tests and medications were described. The index date was defined as the first recorded diagnosis of NAFLD/NASH. Patients were observed until lost to follow up, death or end of available data. Crude overall, 1-year and 5-year incidence rates of key clinical outcomes were calculated per 10,000 person years and survival described with Kaplan-Meier curves. A proxy for cardiovascular death was used whereby patients with a key cardiovascular diagnosis in the 60 days prior to death were considered as cardiovascular deaths.

RESULTS: Of 22,444 patients with NAFLD/NASH diagnoses, the mean age (years) was 57.96 and sex was evenly distributed (male 50.45%; female, 49.55%). The cohort was predominantly of white (70.98%) ethnicity. The median Charlson comorbidity score was 2, (interquartile range 1-3). The most common active comorbidity was mild liver disease (97.48%), followed by hypertension (40.88%), and diabetes (28.41%). Overall, 49,834 person years were observed. The overall crude incidence rate (95% confidence interval) for key clinical outcomes were: death, 763.53 (739.27, 787.80); liver failure 90.71 (82.24, 99.17); HCC, 42.12 (36.37, 47.88) ; and MACE, 437.16 (418.48, 455.84). Across all outcomes, event rates were highest immediately following NAFLD/NASH diagnosis.

CONCLUSIONS: NAFLD/NASH patients continue to be at risk of liver failure, HCC, and MACE, especially in the short period following diagnosis potentially due to under-diagnosis of early-stage NAFLD/NASH. Further research is required to improve early-stage diagnosis.