Abstract
Background and aimsSteatotic liver disease (SLD) is independently associated with cardiovascular disease; however, data on cardiac arrhythmias across individual SLD subtypes remain scarce. This study aimed to investigate associations between distinct SLD subtypes and arrhythmia risk.MethodsUsing prospective UK Biobank data, participants were classified into four groups: no-SLD, metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-associated steatotic liver disease (MetALD), and alcohol-associated liver disease (ALD). The primary outcome was incident overall arrhythmias, and secondary outcomes were specific arrhythmia subtypes. Multivariable Cox proportional hazards models assessed associations, and exploratory analyses evaluated subtype-specific risk patterns.ResultsAmong 428,609 participants followed for a median of 14.23 years (IQR: 12.64-15.30), the cumulative incidence of arrhythmias increased progressively from no-SLD to MASLD, MetALD, and ALD (8.22%, 13.60%, 14.15%, and 16.43%, respectively). All SLD subtypes were independently associated with a higher risk of overall arrhythmias (MASLD: aHR = 1.39, 95% CI 1.36-1.42; MetALD: aHR = 1.43, 95% CI 1.38-1.48; ALD: aHR = 1.65, 95% CI 1.57-1.74; all P < 0.001). Atrial fibrillation and flutter (AF/AFL) accounted for 85.39% of tachyarrhythmias, and risk increased stepwise across the MASLD-MetALD-ALD spectrum. In contrast, bradyarrhythmias showed a distinct risk hierarchy, with MetALD conferring the highest risk (aHR = 1.44, 95% CI 1.32-1.56; P < 0.001), followed by MASLD (aHR = 1.39, 95% CI 1.32-1.47; P < 0.001) and ALD (aHR = 1.38, 95% CI 1.21-1.58; P < 0.001). Exploratory analyses suggested that alcohol-related subtypes were more strongly associated with tachyarrhythmias than with bradyarrhythmias.ConclusionsSLD subtypes were independently associated with a higher risk of incident arrhythmias, and the risk of AF/AFL increased stepwise across the MASLD-MetALD-ALD spectrum. Bradyarrhythmia risk was predominantly observed in metabolically related SLD subtypes. These findings suggest that SLD subtype classification is a relevant consideration for future risk stratification research, although its clinical applicability warrants further investigation.Graphical abstract</p>