The impact of diabetes on giant negative T-wave amplitude in apical hypertrophic cardiomyopathy patients

Clinical observations indicate an attenuation of giant negative T-waves (GNTWs) in some patients with apical hypertrophic cardiomyopathy (ApHCM), a condition frequently comorbid with type 2 diabetes mellitus (T2DM). The objective of this study was to examine the effect of T2DM on the GNTWs amplitude in ApHCM. A retrospective cohort of 124 ApHCM patients from Changzhou First People's Hospital (2021-2024) was categorized into T2DM (<i>n</i> = 30) and non-T2DM (<i>n</i> = 94) groups per American Diabetes Association criteria. A comparative analysis of baseline characteristics was conducted using Kruskal-Wallis and χ² tests. The association between T2DM and maximal negative T-wave voltage (Tmax) was assessed via multivariable linear regression, while nonlinear relationships were explored with generalized additive models (GAM). The T2DM subgroup exhibited a higher prevalence of hypertension (83.3 % vs. 60.6 %, <i>p</i> = 0.022) and coronary artery disease (44.8 % vs. 19.4 %, <i>p</i> = 0.006). The T2DM group demonstrated significantly lower absolute magnitude of both R-waves [3.000 (2.118, 3.775) mV vs. 3.625 (2.615, 4.400) mV, <i>p</i> = 0.045] and GNTWs (Tmax) [- 0.600 (-0.700, 0.400) mV vs. -0.750 (-1.100, 0.500) mV, <i>p</i> = 0.016]. Multivariable analysis identified T2DM as an independent predictor of attenuated GNTWs (<i>β</i> = 0.272, <i>p</i> = 0.016). GAM confirmed a significant nonlinear inverse correlation between T2DM and T-wave amplitude (<i>p</i> < 0.05). In conclusion, T2DM is independently associated with lower absolute magnitude of GNTWs in ApHCM, potentially obscuring characteristic electrocardiographic features. It is incumbent upon clinicians to take these diabetes-related confounding effects into account during diagnostic evaluation.