Increased Ratio of Total Testosterone to Dihydrotestosterone May Predict an Adverse Metabolic Outcome in Polycystic Ovary Syndrome

Abstract

Background: Androgen excess may correlate with metabolic risk in polycystic ovary syndrome (PCOS). The aim of the study was to determine the role of total testosterone to dihydrotestosterone (TT/ DHT) ratio in assessing the adverse metabolic outcome in PCOS. Methods:This cross-sectional study encompassed 40 PCOS women recruited on the basis of revised Rotterdam criteria 2003, and 40 agematched control subjects. TT, sex hormone binding globulin (SHBG) and insulin levels were measured by chemiluminescent microparticle immunoassay (CMIA) while DHT by enzyme-linked immunosorbent assay (ELISA). In addition, TT/DHT ratio, free androgen index (FAI), and insulin resistance (IR) by homeostatic model of assessment of insulin resistance (HOMA-IR) were calculated.Results: TT/DHT ratio was significantly higher in PCOS group than control group (P < 0.001). No significant difference was found for DHT (P = 0.261). PCOS patients had significantly higher TT (0.69 ± 0.26 vs. 0.30 ± 0.13 ng/mL; P < 0.001), FAI (P < 0.001) and low SHBG (P = 0.004) compared to controls. TT/DHT ratio was significantly higher in PCOS with impaired glucose tolerance (IGT) (P = 0.037) and metabolic syndrome (MetS) (P = 0.041). The best cutoff value for TT/DHT ratio to diagnose PCOS was observed to be 2.38 (sensitivity: 70%, specificity: 32.5% and area under the curve (AUC): 0.753). TT/DHT ratio also showed positive correlation with weight (r = 0.323, P = 0.042), waist circumference (WC) (r = 0.372, P = 0.018), HOMA-IR (r = 0.385, P = 0.014), 2-h post 75-g glucose (2h-PG), (r = 0.413, P = 0.008) and triglyceride (TG) level (r = 0.402, P = 0.010) in PCOS. Conclusions:There is a close relation between the TT/DHT ratio and adverse metabolic outcome in PCOS. Therefore, TT/DHT ratio may be considered as a predictor of adverse metabolic findings in PCOS.