Free Androgen Index And Irisin In Polycystic Ovary Syndrome

Context: Polycystic ovary syndrome(PCOS) is the most common endocrinopathy in the female population and is characterized by both reproductive and metabolic aberrations. PCOS is associated with hyperandrogenism and insulin resistance(IR). Recent studies have shown that circulating Irisin levels increase in PCOS women. However, no report has demonstrated a relationship between Irisin and hyperandrogenism in PCOS women.Objective: The purpose of the study was to compare interrelationship between Irisin or androgen excess with IR in PCOS and normal subjects.Design and Patients: 166 PCOS and 103 control women were prospectively studied. Euglycemic-hyperinsulinemic clamps were preformed to assess their insulin sensitivity, which was expressed as M value. Circulating Irisin was determined by ELISA kit.Results: PCOS women with high FAI had significantly higher Irisin levels than PCOS women with low FAI or the controls(203.0±83.6 vs.174.5 ± 61.2 and 157.0 ± 58.8 μ g/L, P<0.05 or P< 0.01). Pearson correlations showed that in the entire population, FAI correlated positively with BMI, WHR, FAT%, blood pressure, TG, DHEA-S, LH/FSH,AUCinsulin, HOMA-IR and Irisin, and negatively with M values. In multiple stepwise regression analysis, only FAT%, DHEA-S, LH/FSH and Irisin were independent related factors with FAI.Conclusions: The elevated Irisin levels in PCOS women wereassociated with androgen excess. Circulating Irisin is a primary predictor of hyperandrogenism, MetS and IR in PCOS women.