Prevalence and Impact of Nonalcoholic Fatty Liver Disease in Atrial Fibrillation

Objective: To estimate the prevalence of nonalcoholic fatty liver disease (NAFLD) and its impact on bleeding and thrombotic events in patients with atrial fibrillation (AF). Patients and Methods: Prospective multicenter cohort study including patients with nonvalvular AF receiving vitamin K antagonists (VKAs) or non-VKA oral anticoagulants (NOACs) from February 2008 for patients on VKA and from September 2013 for patients on NOACs. NAFLD was diagnosed using the validated fatty liver index, with a cutoff score of 60 or higher. Primary end points were the occurrence of major bleedings and cardiovascular events (CVEs). Results: NAFLD was diagnosed in 732 of 1735 (42.2%) patients. Patients with NAFLD were younger, less frequently women, and more likely to be treated with NOACs and to have obesity, dyslipidemia, and persistent/permanent AF. During a median follow-up of 18.7 months (3155 patient-years), we recorded 78 major bleedings (incidence rate, 2.5% per year): 29 (2.1% per year) in patients with and 49 (2.7% per year) in patients without NAFLD (log-rank test P=.23). Univariate Cox proportional regression analysis showed no association of NAFLD with major bleedings (hazard ratio, 0.75; 95% CI, 0.47-1.20; P=.23). One hundred fifty-five CVEs occurred (incidence rate, 3.1% per year). No significant association was found between NAFLD and CVEs (log-rank test P=.12). In the entire population, NOAC use was associated with lower CVEs compared with VKAs (hazard ratio, 0.61; 95% CI, 0.42-0.89; P=.01). Conclusion: NAFLD is highly prevalent in AF but is not associated with higher bleeding or thrombotic risk.