Associations of non-alcoholic fatty liver disease with arrhythmic disorders and electrocardiogram traits: A Mendelian...

Observational studies indicate a link between arrhythmias, electrocardiogram (ECG) characteristics, and non-alcoholic fatty liver disease (NAFLD). However, it is uncertain whether NAFLD acts merely as a risk marker or directly contributes to the development and progression of these arrhythmic disorders. Mendelian randomization (MR) was employed to investigate the causal relationship of NAFLD on arrhythmias and ECG traits.

A two-sample Mendelian randomization (MR) analysis was performed to examine the causal relationship of genetically predicted NAFLD (imaging and biopsy confirmed NAFLD) on arrhythmias [i.e., atrial fibrillation (AF), left bundle branch block (LBBB), right bundle branch block (RBBB), and atrioventricular block (AVB)] and ECG traits [i.e., P wave duration (PWD), PR interval, QT interval, and QRS duration]. We utilized the inverse variance weighted method as the principal analytical approach, supplemented by a range of sensitivity analyses.

Inverse-variance weighted method showed a statistically significant association between genetically predicted NAFLD and LBBB (OR: 1.261, 95% CI: 1.066-1.491, p = 0.0068). However, there was insufficient evidence to support a significant association between genetically predicted NAFLD and other arrhythmias or electrocardiographic characteristics. Sensitivity analyses revealed low heterogeneity and the absence of horizontal pleiotropy, suggesting that the findings are robust.

The study indicates a causal relationship between genetically predicted NAFLD and LBBB, suggesting that NAFLD may influence cardiac electrical activity.