Association of Non-alcoholic Fatty Liver Disease with Conduction Defects on Electrocardiogram

Background: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of liver disease in developed countries. The association of NAFLD with conduction defects is unknown. The aim of our study was to find whether an association exists between conduction defects and NAFLD. Methods: This is a case-control retrospective study of 700 patients admitted to Orange Park Medical Center, Orange Park, Florida from 2009 to 2015. Patients with a history of alcohol use, congenital heart disease, infiltrative malignancy, and myocarditis were excluded from the study. NAFLD was diagnosed by detection of hepatic steatosis on abdominal ultrasound or computerized tomography (CT) scan. Electrocardiograms (EKGs) were performed on all 700 patients and were interpreted by a cardiologist. Univariate logistic regression was used to assess the association between NAFLD and the variables of demographics, clinical characteristics, medicine use, EKG changes, and conduction defects, while multivariate logistic regression with backward elimination method was performed to determine if NAFLD is one of the most important risk factors for conduction defects. Results: The study population included 408 patients with NAFLD and 292 patients with No-NAFLD. A total of 155 conduction defects occurred in 140 patients; conduction defects included 25.7% (36) patients with first degree block, 2.1% (three) patients with Mobitz type 1 block, 41.4% (58) patients with right bundle branch block (RBBB), 17.9% (25) patients with left bundle branch block (LBBB), 11.4% (16) patients with bifascicular block, and 12.1% (17) patients with nonspecific intraventricular block. Multivariate logistic regression with backward elimination method identified six risk factors for conduction defects; these included NAFLD (odds ratio (OR) 2.38; 95% confidence interval (CI) 1.51-3.73, p<0.0001), hypertrophy (OR 2.52; 95% CI 1.57-4.05, p=0.0001), congestive heart failure (CHF) (OR 3.05; 95%CI 1.46-6.38, p=0.0031), male sex (OR 1.79; 95%CI 1.19-2.69, p=0.0051), diabetes mellitus (OR 1.63; 95% CI 1.08-2.47, p=0.02), and age (OR 1.04; 95% CI 1.02-1.06, p<0.0001). Conclusion: NAFLD is associated with conduction defects. Prospective randomized trials are needed to demonstrate that NAFLD causes conduction defects.