People with metabolic dysfunction–associated steatotic liver disease had a significantly higher risk of developing atrial fibrillation compared with those without liver disease, according to a nationwide study in Korea.
The increased atrial fibrillation (AF) risk was evident regardless of alcohol consumption, suggesting that metabolic dysfunction plays a central role in the development of this common arrhythmia.
The study followed 206,455 Korean adults for a median of 9.6 years. During this time, 5,335 individuals developed new-onset atrial fibrillation, an incidence rate of 2.74 cases per 1,000 person-years.
Participants were grouped into four categories based on liver disease status and alcohol use: no liver disease without alcohol, metabolic dysfunction–associated steatotic liver disease (MASLD) without alcohol, no liver disease with alcohol, and MASLD with alcohol or metabolic dysfunction–associated steatotic liver disease with increased alcohol intake (MetALD).
The highest incidence of AF occurred in the MASLD without alcohol group, with 1,374 cases over 360,987 person-years (3.81 per 1,000 person-years). This was followed by the MASLD with alcohol or MetALD group, with 1,074 cases over 332,362 person-years (3.23 per 1,000 person-years).
In comparison, the no liver disease without alcohol group recorded 2,068 cases over 874,020 person-years (2.37 per 1,000 person-years), while the no liver disease with alcohol group had 819 cases over 383,094 person-years (2.14 per 1,000 person-years).
After adjusting for age, sex, comorbidities, and lifestyle factors, the risk of developing AF was 1.32 times higher in the MASLD without alcohol group (95% CI, 1.23–1.41; P<.001) and 1.48 times higher in the MASLD with alcohol and MetALD group (95% CI, 1.36–1.61; P<.001), compared with the no liver disease without alcohol group.
When comparing nondrinking MASLD participants to all alcohol consumers, regardless of liver disease status, the MASLD without alcohol group still showed significantly higher AF risk. The adjusted hazard ratio was 1.11 (95% CI, 1.02–1.20; P=.011).
Secondary outcomes showed similar patterns. Ischemic stroke occurred in 4,910 participants (2.52 per 1,000 person-years), and heart failure developed in 2,414 participants (1.23 per 1,000 person-years), both more frequent in MASLD groups.
The study used the fatty liver index to define MASLD, along with self-reported alcohol intake and established cardiometabolic risk factors. Participants with viral hepatitis, liver cancer, or heavy alcohol use were excluded.
“These findings suggest that metabolic dysfunction plays a more significant role in AF occurrence than the direct toxic effects of alcohol,” said Minkwan Kim, MD, PhD, of the Division of Cardiology at Yongin Severance Hospital, Yonsei University College of Medicine.
The findings suggest that metabolic dysfunction may be a more important contributor to AF than alcohol intake, emphasizing the need for cardiovascular monitoring in patients with MASLD.
Full disclosures can be found in the published study.
Source: JAHA