ASSOCIATION OF TRIGLYCERIDE-GLUCOSE INDEX AND SUBCLINICAL LEFT VENTRICULAR SYSTOLIC DYSFUNCTION IN YOUNG HYPERTENSIVE SUBJECTS

Abstract

Objective: Triglyceride-glucose (TyG) index is a marker of insulin resistance (IR) which has previously appeared to be a promising predictor of hypertension (HTN), coronary artery calcification and non-alcoholic fatty liver disease. However, the interrelation between TyG index and subclinical left ventricular systolic dysfunction has never been studied. Design and method: We evaluated anthropometric and metabolic characteristics, clinical blood pressure and performed 24-hours ambulatory blood pressure monitoring (ABPM) and echocardiography including two-dimensional speckle tracking in 94 young treatment-naive hypertensives (age 23 [21;25] years, 85,1% males, body mass index (BMI) 25,88 ± 4,78 kg/m2) free of diabetes mellitus. Most patients (67%) had masked HTN and diagnosis was stated with ABPM. IR was estimated with HOMA-IR and TyG index which was calculated as ln[fasting triglycerides (mg/dL) × fasting plasma glucose (mg/dL)/2]. All patients were divided in two subgroups according to LV GLS median, e.g. with GLS of -20,05 or less and > -20,05. Then we compared main clinical variables including obesity and metabolic characteristics and blood pressure levels in derived subgroups. We used Student's t-test and Mann-Whitney U-test to compare variables with normal and non-normal distribution, respectively. To investigate the relationship between IR indices and GLS we performed simple and multiple linear regression analysis. Results: The subgroups were comparable in age, sex and race composition; there was also no significant difference in BMI, waist circumference (WC), waist-to-hip ratio (WHR), WC to height ratio. Insulin and HOMA-IR values were identical. The groups were significantly different in triglycerides levels (0,86 ± 0,31 vs 1,32 ± 0,79 mmol/L for GLS < -20,05 and > -20,05, respectively, p < 0,001) and TyG index (8,05 ± 0,39 vs 8,44 ± 0,55, respectively, p < 0,05). 24-hours SBP and DBP were higher in group with worse GLS: 131,2 ± 11,4 vs 139,3 ± 16,7 mm Hg and 77 [73;85,5] mm Hg, respectively, with p < 0,05 for both. In simple linear regression TyG index was a significant predictor of GLS value with beta = 0,407 (p < 0,001). After addition of age, sex, WHR and office DBP into the model TyG index remained independently associated with GLS with beta = 0,253 (p < 0,05). Conclusions: In young hypertensives TyG index is an independent predictor of GLS impairment.