Endocrine Abstracts

Introduction: It is well known that patients with hypogonadism are at increased risk for insulin resistance and cardiovascular diseases. In many studies homeostatic model assessment-insulin resistance (HOMA-IR) formulation is used for the evaluation of insulin resistance. Recently, a simple and inexpensive approach to evaluate for insulin resistance has been developed, the Triglyceride – Glucose (TyG) index. This particular index is based on measuring the levels of fasting triglycerides and glucose. This study investigated the TyG index as a useful surrogate marker of insulin resistance among patients with congenital hypo gonadotrophic hypogonadism (CHH).

Methods: A total of 154 young male patients with CHH (mean age: 21.54±1.95 years) and 115 healthy control subjects (mean age: 22.81±1.45 years) were enrolled in the study. The demographic and laboratory parameters, plasma ADMA, hsCRP, HOMA-IR levels and TyG index were measured in healthy controls and patients with CHH, before and after TRT.

Results: The patients had higher waist circumference (WC, P=0.011), systolic blood pressure (SBP, P=0.011), triglycerides (Tg, P<0.001), insulin (P<0.001), asymmetric dimethylarginine (ADMA, P<0.001), HOMA-IR (P<0.001) and TyG index (P=0.004) levels and lower follicle stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone (P<0.001 for all) levels than the healthy controls. After 5.85±2.13 months of TRT, the patients had significantly elevated BMI (P<0.001), WC (P<0.001), SBP (P=0.002), Tg (P<0.001), total testosterone (P=0.012), HOMA-IR (P<0.001), ADMA (P<0.001) and TyG index (P<0.001) and decreased HDL-C levels (P<0.001). There was also a significant correlation between TyG index and BMI (r=0.15, P=0.03), WC (r=0.25, P<0.001), HDL-C (r=−0.21, P=0.001), LDL-C (r=0.15, P=0.032) and ADMA (r=0.17, P=0.03) levels.

Conclusion: The results of the present study show that patients with CHH have elevated TyG index which is an easily calculated and inexpensive parameter that can indicate insulin resistance. TyG index is further increased after TRT and also related to surrogate marker of endothelial dysfunction. Prospective follow-up studies are warranted to clarify the role of TyG index in predicting cardiometabolic risk in patients with hypogonadism.