Intrinsic factors rather than vitamin D deficiency are related to insulin resistance in lean women with polycystic ovary syndrome

OBJECTIVE: To investigate the correlation between insulin resistance (IR) and serum 25-OH-Vit D concentrations and hormonal parameters in lean women with polycystic ovary syndrome (PCOS). PATIENTS AND METHODS: 50 lean women with PCOS and 40 body mass index (BMI) matched controls were compared in terms of fasting insulin and glucose, homeostatic model assessment insulin resistance (HOMA-IR), 25-OH-Vit D, high sensitivity C-reactive protein (hs-CRP), luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone, dehydroepiandrosterone sulfate (DHEA-S), total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides and Ferriman-Gallway (FG) scores. Correlation analyses were performed between HOMA-IR and metabolic and endocrine parameters. RESULTS: 30% of patients with PCOS demonstrated IR. Levels of 25-OH-Vit D, hsCRP, cholesterol, HDL, LDL, triglyceride and fasting glucose did not differ between the study and control groups. Fasting insulin, HOMA-IR, LH, total testosterone, and DHEA-S levels were higher in PCOS group. HOMA-IR was found to correlate with hs-CRP and total testosterone but not with 25-OH-Vit D levels in lean patients with PCOS. CONCLUSIONS: An association between 25-OH-Vit D levels and IR is not evident in lean women with PCOS. hs-CRP levels do not indicate to an increased risk of cardiovascular disease in this population of patients. Because a strong association between hyperinsulinemia and hyperandrogenism exists in lean women with PCOS, it is advisable for this population of patients to be screened for metabolic disturbances, especially in whom chronic anovulation and hyperandrogenism are observed together.