Associations of body roundness index with steatotic liver disease and mortality from the UK biobank cohort study

Abstract

Background Steatotic liver disease (SLD) is a chronic condition associated with cardiometabolic risk. The body roundness index (BRI) is a novel visceral adiposity marker. We evaluate the associations between BRI and risks of SLD, major adverse liver-related outcomes (MALO), liver-related mortality, and all-cause mortality using the UK Biobank cohort. Methods Data from 399,115 participants (aged 37-73 years) without baseline SLD or MALO were analyzed. BRI was categorized into sex-specific quartiles. Outcomes were identified via national health records. Adjusted hazard ratios (HRs) were estimated using Fine-Gray competing risk models and Cox proportional hazards models. Results During a median follow-up of 13.9 years, the incidence of SLD, MALO, liver-related mortality, and all-cause mortality was 1.38%, 1.25%, 0.24%, and 8.31%, respectively. Higher BRI was significantly associated with increased SLD risk (HR 6.20; 95% CI 5.28-7.28), with a more pronounced association in women (HR 9.11) than in men (HR 3.38). Significant non-linear, J-shaped associations were observed for SLD and all-cause mortality (both p for nonlinearity<0.001). Conversely, MALO and liver-related mortality showed linear positive associations (p for nonlinearity> 0.05), with significant risks primarily observed in the highest BRI quartiles. Conclusion Higher BRI is significantly associated with increased risks of SLD, MALO, and both liver-related and all-cause mortality. These findings suggest that BRI is a valuable tool for identifying individuals at risk of adverse hepatic outcomes, potentially offering predictive utility beyond conventional anthropometric indices.