Triglyceride glucose index is related with cardiac autonomic dysfunction in patients with metabolic syndrome

Aim    Cardiac autonomic dysfunction is encountered in approximately 25 % of patients with metabolic syndrome (MetS). 24 hr Holter-ECG based heart rate variability (HRV) and heart rate turbulence (HRT) parameters are used to evaluate cardiac autonomic function. We aimed to investigate the relationship between a novel insulin resistance marker, triglyceride glucose (TyG) index and cardiac autonomic dysfunction in patients with MetS.Material and methods    We examined a total of 400 non-diabetic subjects, 136 with MetS and 264 without MetS. All underwent TyG index calculations, and 24 hr Holter-ECG recordings for the measurement of HRV and HRT parameters.Results    HRV and HRT parameters were lower or higher in patients with MetS than in subjects without MetS, indicating cardiac autonomic dysfunction. We observed significant correlations between TyG index and measures of cardiac autonomic function. Multiple linear regression analysis showed that the TyG index was an independent predictor of almost all HRV and HRT parameters.Conclusion    This study demonstrates the independent relationship between cardiac autonomic dysfunction and the TyG index, a novel marker of insulin resistance in non-diabetic patients with MetS.