INSULIN SENSITIVITY IN WOMEN WITH POLYCYSTIC-OVARY-SYNDROME - RELATIONSHIP TO HYPERANDROGENEMIA

Objective: To evaluate the extent of decreased insulin sensitivity in relation to body mass index and its relationship to serum androgens in women with polycystic ovarian syndrome (PCOS). Design: Comparative st udy of endogenous glucose disposal and serum insulin responses to oral glucose load with endocrine parameters in PCOS. Setting: Fertility an d Endocrine Clinics, North Staffordshire Hospital Centre.Patients: For ty-nine obese and 16 nonobese women with PCOS were compared with 18 ob ese and 16 nonobese control women with regular ovulatory cycles and no features of PCOS. Main Outcome Measures: Basal concentrations of seru m LH, FSH, T, androstenedione, sex hormone-binding globulin (SHBG), an d free T index. Measurements of insulin sensitivity by rate of endogen ous glucose disposal after IV bolus injection of insulin and glucose m ediated insulin responses. Results: Obese women with PCOS showed decre ased insulin sensitivity and hyperinsulinemia to an extent greater tha n can be explained by obesity alone. Serum insulin showed inverse corr elation with SHBG, and therefore hyperinsulinemia increased the bioava ilability of androgens in obese PCOS. In nonobese PCOS, this method of assessment failed to reveal insulin resistance. Conclusion: Hyperandr ogenemia and insulin resistance are independent features of PCOS. Hype rinsulinemia enhances expression of hyperandrogenemia by increasing bi oavailability of androgens.