Exploring the link between atherosclerosis indicators and QT interval in type 2 diabetes: a retrospective...

A prolonged QT interval is a recognized risk factor for life-threatening arrhythmias and sudden cardiac death. In patients with type 2 diabetes, identifying clinical markers associated with myocardial repolarization abnormalities is essential for risk stratification.

To investigate the association between multiple non-invasive atherosclerosis indicators and corrected QT interval prolongation in patients with type 2 diabetes.

Retrospective cross-sectional analysis.

We evaluated 96 patients with type 2 diabetes admitted for glycemic control. The QTc interval was calculated using the Bazett (QTcB), Fridericia (QTcF), and Framingham (QTcFra) formulas. We examined the association between QTc and multiple atherosclerosis indicators, including the ankle-brachial index (ABI), cardio-ankle vascular index (CAVI), carotid intima-media thickness (IMT), and flow-mediated dilatation (FMD).

Among all participants, 2 women (7%) and 10 men (15%) had prolonged QTcB. In univariate analyses, FMD was negatively correlated with QTcB (r = -0.28, p = 0.0054), whereas ABI, CAVI, mean, and maximum carotid IMT did not exhibit significant associations. In multivariable linear regression analyses, FMD was independently associated with QTcB (unstandardized coefficient β = -1.95 ms per 1% increase in FMD; 95% confidence interval -3.60 to -0.30; p = 0.021). Subgroup analysis revealed that this association was prominent specifically in the non-obese group (body mass index, <25 kg/m²). Notably, these findings remained consistent regardless of the correction formula used.

Vascular endothelial dysfunction, as measured by FMD, is independently associated with QTc prolongation, particularly in non-obese patients with type 2 diabetes. This suggests a significant link that may help identify individuals at higher risk for life-threatening arrhythmias.