Metabolic dysfunction-associated steatotic liver disease and increased risk of atrial fibrillation in the elderly: A longitudinal cohort study.

Background: Emerging evidence suggests a link between metabolic dysfunction-associated steatotic liver disease (MASLD) and cardiac arrhythmia. This study aims to investigate the potential relationship between MASLD and atrial fibrillation (AF). Methods: This retrospective cohort study included 8511 participants (age > 65 years) without a history of cardiovascular diseases, cancer, or severe kidney dysfunction. MASLD was diagnosed using hepatic ultrasound in the presence of at least one cardiometabolic risk factor. Poisson regression models were employed to estimate the relative risk (RR) of AF, adjusting for potential confounders. Results: Participants were categorized into MASLD (n = 3,926) and non-MASLD (n = 4,585) groups. During a mean follow-up period of 3.65 ± 1.20 years, 307 participants with MASLD developed AF, however, the number in the non-MASLD group was 144 (incidence rate 7.82 % vs. 3.14 %). After adjusting for multiple cardiovascular risk factors, MASLD was associated with increased risk of AF (RR = 1.55, 95 %, confidence interval (CI): 1.12-2.13). Positive correlations were observed between age, body mass index (BMI), systolic and diastolic blood pressure, low-density lipoprotein levels, and AF risk. Subgroup analysis revealed a stronger association between MASLD and AF in participants with BMI < 24 kg/m Conclusion: This study highlights a significant association between MASLD and an increased risk of developing AF. The elevated risk in patients with MASLD may involve mechanisms extending beyond traditional cardiometabolic factors, particularly in individuals with lower BMI. Further experimental research is warranted to elucidate the underlying pathways linking MASLD and AF.