FIB-4 score in young healthy adults and its association with end stage liver disease: a nationwide retrospective study.

OBJECTIVES Metabolic dysfunction-associated steatotic liver disease (MASLD) is highly prevalent and underdiagnosed among young healthy adults, with or without metabolic syndrome. This study assessed whether FIB-4 scores in young healthy adults are associated with incident end stage liver disease (LD). METHODS This retrospective study was conducted using a nationwide community and hospital database. Included were young adults, ages 18-40, with a FIB-4 score calculated during 2005-2020. People diagnosed with liver metastasis or chronic LD, other than MASLD, before or during the study, were excluded. The primary outcome was the first diagnosis of cirrhosis, cirrhosis-related complications, or hepatocellular carcinoma. Cox proportional models were applied, with FIB-4 score categorized by percentiles. RESULTS There were 430 incident cases of end stage LD in 11,057,421 person-years (mean age at diagnosis 30.0 ± 5.3 years). FIB-4 score was associated with incident end stage LD. After adjusting for multiple confounders, people with FIB-4 in the 75th-94th, 95th-98th and ≥ 99th percentiles were 35%, 140% and 760% more likely to develop end stage LD, respectively, compared to people with FIB-4 score in the 5th-49th percentiles. Each point of FIB-4 score was associated with a 2.2-fold greater risk of incident end stage LD (adjusted hazard ratio= 2.21 (95% CI 1.91-2.56). CONCLUSIONS FIB-4 score is associated with increased risk for end stage LD in young healthy adults.