Relationships between adiponectin, sex hormone binding globulin and insulin resistance in hyperthyroid Graves' disease women.

INTRODUCTION Adiponectin and sex hormone binding globulin (SHBG) play a role in glucose metabolism. Hyperthyroidism has an impact on carbohydrate metabolism and could affect insulin resistance. The aim of this study was to assess the associations between insulin resistance, adiponectin and SHBG among hyperthyroid Graves` disease (GD) women. MATERIAL AND METHODS The study was undertaken in 60 women with hyperthyroidism in the course of GD; 32 healthy women matched by BMI and age formed the control group. The concentrations of: free thyroxine (fT4), free triiodothyronine (fT3), thyroid-stimulating hormone (TSH), SHBG, insulin, adiponectin and glucose were measured, and the homeostasis model assessment (HOMA-I) was calculated. RESULTS Compared to euthyroid subjects, hyperthyroid GD women had elevated glucose, fT4, fT3, adiponectin and SHBG concentrations, but there were no differences in HOMA-I. When we explored the relations between adiponectin as well as SHBG with glucose and HOMA-I, we observed that HOMA-I was associated with adiponectin and SHBG only in the control group, and in hyperthyroidism there were no such connections. We found positive associations between adiponectin, SHBG, fT4 and fT3 in the GD group. CONCLUSIONS Elevated concentrations of adiponectin and SHBG were observed in hyperthyroidism but they were not related to insulin resistance.