Extrahepatic disease clusters and mortality in people with steatotic liver diseases: a prospective analysis of 64,749 females and 113,587 males in the UK Biobank.

[BACKGROUND] Steatotic liver disease (SLD) is the most prevalent chronic liver disease worldwide and linked to various liver and extrahepatic diseases. However, the clustering of extrahepatic conditions and their impact on mortality in individuals with SLD remain poorly understood.

[METHODS] We used UK Biobank data to identify sex-specific disease clusters among individuals with SLD and multimorbidity (having ≥ 2 extrahepatic diseases) using latent class analysis. Multivariable Cox models were used to assess associations between multimorbidity, disease clusters and all-cause mortality and mortality from cardiovascular diseases (CVD), extrahepatic cancers, liver-related diseases and hepatocellular carcinoma.

[RESULTS] Among 178,336 (36.3% female) individuals with SLD, during a median follow-up of 13.8 years, multimorbidity increased mortality by 100% (hazard ratio (95% confidence interval): 2.00 (1.93, 2.08)) and 80% (1.80 (1.71, 1.90)) in males and females, respectively, and increased the risk of death from CVD, extrahepatic cancers and liver-related diseases. Among 36,002 (43.9% female) of the 178,336 with multimorbidity, we identified five disease clusters in both sexes: related to respiratory, mental health, cancer/osteoarthritis and cardiovascular diseases. Males had separate heart and stroke clusters, whereas females had a combined heart/stroke cluster and a unique thyroid cluster. CVD was the leading cause of death in cardiovascular clusters, whereas extrahepatic cancers were the most common cause of death in other clusters. Among all disease clusters, cardiovascular clusters exhibited the highest all-cause mortality risk: 2.90 (2.64, 3.20) for the heart/stroke cluster in females and 2.63 (2.48, 2.78) for the heart cluster and 2.36 (2.16, 2.58) for the stroke cluster in males. All clusters exhibited increased mortality of CVD and extrahepatic cancers.

[CONCLUSIONS] Multimorbidity doubled the death rate in people with SLD. Common multimorbidity clusters of mental health, respiratory, cancer and cardiovascular diseases were found and were associated with varying mortality, with cardiovascular-related clusters showing the highest risk. Females exhibited a unique thyroid disease cluster. These findings highlight the need for tailored prevention and management strategies in SLD populations.