The insulin-resistant phenotype of polycystic ovary syndrome

Abstract

To investigate the individual parameters included in the diagnosis of polycystic ovary syndrome (PCOS), and their impact on insulin sensitivity. Cross-sectional study. Department of Obstetrics and Gynaecology, Copenhagen University Hospital, Hvidovre, Denmark. Sixty-one women; 36 women with PCOS and 25 age- and weight-matched control women were investigated. Peripheral insulin sensitivity was evaluated by the hyperinsulinemic euglycemic clamp, glucose tolerance by an oral glucose tolerance test (OGTT), and ovarian morphology by transvaginal ultrasonography (TVS). The Rotterdam criteria were used for diagnosing PCOS, and hirsutism was evaluated by the Ferriman Gallwey score. Insulin sensitivity was calculated as the insulin sensitivity index, and whole body insulin sensitivity was assessed by the homeostatic model assessment insulin resistance (IR) index. Multiple regression analysis showed that body mass index (BMI) and hirsutism were independent predictors of IR evaluated by insulin sensitivity index, whereas BMI, total T, and hirsutism were independent predictors of IR evaluated by the homeostatic model assessment IR index. We found no significant association between ovarian morphology and insulin sensitivity or between menstrual frequency and insulin sensitivity. The PCOS is associated with IR. Body mass index, hyperandrogenemia, and hyperandrogenism are independent predictors of low insulin sensitivity.