The effect of gonadal replacement on insulin resistance in hypogonadal adult men with GH deficiency
Marko Stojanovic, Sandra Pekic, Mirjana Doknic, Dragana Miljic, Marina Nikolic-Djurovic & Vera Popovic
Introduction: Both GH deficiency (GHD) and male hypogonadism are thought to be associated with an increased cardiovascular morbidity and mortality which is at least partly attributed to higher Insulin resistance. Potential reversibility of increased risk factors after gonadal replacement was assessed in this study, by comparing replaced and unreplaced hypogonadal men with GHD.
Subjects and methods: Seventy-seven hypogonadal adult male patients with GHD have been divided in two groups according to their gonadal replacement status: hypogonadal GHD patients on standard monthly testosterone replacement (n=42), and unreplaced hypogonadal GHD men (n=35). Body mass index (BMI) and waist to hip ratio (WHR) were calculated from standard anthropometric measures. Glycaemia and insulinaemia were followed in OGTT with area under the curve (AUC) and HOMA index calculated.
Results: Unreplaced hypogonadal GHD men had a significantly higher WHR compared to replaced hypogondal GHD men (0.98±0.11 vs 0.95±0.13; P<0.05). OGTT revealed that unreplaced hypogonadal GHD men had a significantly higher basal insulin (16.36±1.57 vs 12.25±1.02 mU/l; P<0.05), significantly higher insulin peak (127.39±17.14 vs 75.52±7.36 mU/l; P<0.05) and significantly higher insulin AUC (8365.5±1093.8 vs 5050.0±468.4 mU/l per 120 min; P<0.05) in OGTT, and significantly higher HOMA index (3.24±0.32 vs 2.41±0.23; P<0.05) as compared to replaced hypogondal GHD men.
Conclusion: Gonadal replacement in hypogonadal adult men with GHD appears to positively influence parameters of Insulin resistance such as WHR, peak insulin and insulin AUC in OGTT and HOMA index.