Background and aims: The relationship between nonalcoholic fatty liver disease (NAFLD) and prolonged heart rate-corrected QT (QTc) interval, a risk factor for ventricular arrhythmias and sudden cardiac death, is currently unknown. We therefore examined the relationship between NAFLD and QTc interval in patients with type 2 diabetes.
Methods and results: We studied a random sample of 400 outpatients with type 2 diabetes. Computerized electrocardiograms were performed for analysis and quantification of QTc interval. NAFLD was diagnosed by ultrasonographic detection of hepatic steatosis in the absence of other liver diseases. Mean QTc interval and the proportion of those with increased QTc interval (defined as either QTc interval above the median, i.e. ≥416 ms, or QTc interval >440 ms) increased steadily with the presence and ultrasonographic severity of NAFLD. NAFLD was associated with increased QTc interval (odds ratio [OR] 2.16, 95% CI 1.4-3.4, p < 0.001). Adjustments for age, sex, smoking, alcohol consumption, BMI, hypertension, electrocardiographic left ventricular hypertrophy, diabetes-related variables and comorbid conditions did not attenuate the association between NAFLD and increased QTc interval (adjusted-OR 2.26, 95% CI 1.4-3.7, p < 0.001). Of note, the exclusion of those with established coronary heart disease or peripheral artery disease from analysis did not appreciably weaken this association.
Conclusion: This is the first study to demonstrate that the presence and severity of NAFLD on ultrasound is strongly associated with increased QTc interval in patients with type 2 diabetes even after adjusting for multiple established risk factors and potential confounders.
Keywords: Arrhythmias; Cardiovascular risk; Liver fat; Nonalcoholic fatty liver disease; Type 2 diabetes.
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