BACKGROUND: Obesity is an important risk factor for nonalcoholic fatty liver disease and atrial fibrillation (AF). Less is known about the relations between nonalcoholic fatty liver disease and AF. We sought to evaluate the association between fatty liver and prevalent and incident AF in the community.

METHODS AND RESULTS: We examined Framingham Heart Study participants who underwent a study-directed computed tomography scan, had hepatic steatosis (HS) evaluated, and did not report heavy alcohol use between 2002 and 2005. We evaluated cross-sectional associations between liver fat and prevalent AF with logistic regression models. We assessed the relations between liver fat and incident AF during 12-year follow-up with Cox proportional hazards models. Of 2122 participants (53% women; mean age, 59.0+/-9.6 years), 20% had HS. AF prevalence (n=62) among individuals with HS was 4% compared to 3% among those without HS. There was no significant association between HS (measured as continuous or dichotomous variables) and prevalent AF in age- and sex-adjusted or multivariable-adjusted models. Incidence of AF (n=153) among participants with and without HS was 8.7 cases and 7.8 cases per 1000 person-years, respectively. In age- and sex-adjusted and multivariable-adjusted models, there were no significant associations between continuous or dichotomous measures of HS and incident AF.

CONCLUSIONS: In our community-based, longitudinal cohort study, liver fat by computed tomography scan was not significantly associated with increased prevalence or incidence of AF over 12 years of follow-up.