Abstract
Atrial fibrillation (AF) risk is influenced by sex hormones and steatotic liver disease (SLD), but their interplay in women remains unclear. We aimed to evaluate the impact of various SLD statuses on AF risk among premenopausal and postmenopausal women. Total 2,181,691 women from the 2009 Korean National Health Insurance Service screenings were analyzed, excluding those with prior AF, hysterectomy, liver cancer, or transplantation. Participants were classified by menopausal status and SLD type: No SLD, metabolic dysfunction-associated steatotic liver disease (MASLD), MASLD with combined etiologies, MASLD and increased alcohol intake (MetALD), and alcohol-associated liver disease (ALD). Over 8.3 years of follow-up, postmenopausal women (n = 903,079) were older with higher body mass index and comorbidities, while premenopausal women (n = 1,278,613) more often smoked and consumed alcohol. In premenopausal women, AF incidence ranged from 0.65 per 1,000 person-years without SLD to 1.67 in ALD, with the highest hazard ratio in ALD (HR 2.16, 95% CI 1.27-3.67). Postmenopausal women showed higher absolute AF incidence (3.43-5.44) but attenuated hazard ratios, peaking at 1.66 in ALD. SLD is significantly associated with increased AF risk, peaking in premenopausal women with MASLD or ALD; these findings necessitate early cardiovascular risk assessment and AF screening, warranting further research into preventive strategies. These novel findings establish a significant association between SLD and increased AF risk across all menopausal stages, demonstrating that the highest relative risk is disproportionately concentrated in premenopausal women with MASLD or ALD, thus underscoring the urgent need for enhanced cardiovascular surveillance and status-specific primary prevention strategies in this overlooked younger population.