Background: Insulin resistance is a common finding in both obese and lean women with polycystic ovary syndrome (PCOS). Factors contributing to insulin resistance are still controversial. The purpose of the study was to compare the tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) concentrations in normal weight women with PCOS and a weightmatched healthy control group, and also to evaluate the role of these cytokines in the pathogenesis of insulin resistance.
Methods: Thirty-two women with PCOS and 25 age- and weight-matched healthy controls participated in this study. Patients were evaluated clinically and by pelvic ultrasound. Fasting insulin, glucose, lipid profile, follicle-stimulating hormone (FSH), leutinizing hormone (LH), prolactin, testosterone, sex hormone binding globulin (SHBG), 17-hydroxyprogesterone, IL-6, TNF-alpha concentrations, and insulin sensitiviy indices homeostasis model assessment (HOMA) and quantitative insulin sensitivity check index (QUICKI) were measured.
Results: TNF-alpha and IL-6 concentrations were significantly higher in women with PCOS than in the control group. Significant correlations were found between TNF-alpha serum concentrations and Body Mass Index (BMI), waist circumference, triglyceride concentrations, fasting insulin, and insulin resisitance indices (p < 0.001). IL-6 concentrations were correlated with fasting glucose and insulin resistance (p < 0.05).
Conclusions: The study demonstrated that TNF-alpha and IL-6 concentrations were elevated in normal weight women with PCOS. The findings may contribute to evidence of insulin resistance in lean women with PCOS.