Currently, it remains uncertain whether metabolic dysfunction-associated fatty liver disease (MAFLD) is associated with increased risk of supraventricular and ventricular tachyarrhythmias in people with type 2 diabetes mellitus (T2DM).

We retrospectively examined the data of 367 ambulatory patients with T2DM who underwent 24-hour Holter monitoring between 2015 and 2022 for clinical indications, and who did not have pre-existing permanent atrial fibrillation (AF), kidney failure or known liver diseases. Paroxysmal supraventricular tachycardia (PSVT), paroxysmal AF and episodes of ventricular tachyarrhythmias (i.e., presence of ventricular tachycardia, >30 premature ventricular complexes per hour, or both) were recorded. The presence and severity of MAFLD was diagnosed by ultrasonography and fibrosis-4 (FIB-4) index.

Patients with T2DM who had MAFLD (n = 238) had a significantly greater prevalence of PSVT (51.7% vs. 38.8%), paroxysmal AF (6.3% vs. 1.3%) and combined ventricular tachyarrhythmias (31.9% vs. 20.2%) compared to their counterparts without MAFLD (n = 129). MAFLD was significantly associated with a greater than two-fold risk of having PSVT (adjusted-odds ratio [OR] 2.04, 95% confidence interval 1.04–4.00) or ventricular tachyarrhythmias (adjusted-OR 2.44, 95%CI 1.16–5.11), after adjusting for age, sex, smoking, alcohol intake, diabetes-related factors, comorbidities, medication use and left ventricular ejection fraction on echocardiography. The risk of supraventricular and ventricular tachyarrhythmias was even greater amongst patients with MAFLD and FIB-4 ≥ 1.3.

In ambulatory patients with T2DM, the presence and severity of MAFLD was strongly associated with an increased risk of supraventricular and ventricular arrhythmias on 24-hour Holter monitoring.