Coexistence of atrial fibrillation and metabolic dysfunction-associated steatotic liver disease as a high-risk overlap for incident heart failure in older adults

AIMS: Older adults with atrial fibrillation (AFib) face a high risk of heart failure (HF). We investigated whether the coexistence of AFib and metabolic dysfunction-associated steatotic liver disease (MASLD) and its subtypes, including MASLD with increased alcohol intake (MetALD) and alcoholic liver disease (ALD), further increases the risk of HF. METHODS AND RESULTS: Patients (aged ≥60 years) with AFib diagnosed between 2002 and 2010 were collected from the Korean National Health Insurance Service database. MASLD status was determined during 2009-2010 [fatty liver index (FLI) ≥30]. The association between MASLD and incident HF was assessed using Fine-Gray subdistribution hazard models. Participants were followed from 1 January 2011, until the occurrence of HF, death, or 31 December 2019, whichever came first. Among 7543 older adults with AFib, 3168 had MASLD, 259 had MetALD, and 159 had ALD. The presence of MASLD (subdistribution hazard ratio, 1.22; 95% CI, 1.10-1.35, P < .001), MetALD (1.36; 1.05-1.76, P = .019), and ALD (1.42; 1.03-1.97, P = .034) was associated with a higher risk of incident HF. In restricted cubic spline analyses, significant dose-response relationships were observed for both the FLI and daily alcohol consumption, each of which was associated with increased HF risk among patients with AFib. CONCLUSION: Coexistence of AFib and MASLD identifies a high-risk overlap state for incident HF in older adults. These findings highlight the importance of recognizing inflammatory liver dysfunction driven by metabolic and alcohol-related factors as a potential amplifier of HF risk in older adults with AFib.