Prevalence of polycystic ovary syndrome in Chinese obese women of reproductive age with or without metabolic syndrome

Abstract

To compare the prevalence of polycystic ovary syndrome (PCOS) and related clinical characteristics between metabolically unhealthy obese (MUO) and metabolically healthy obese (MHO) women of reproductive age. Cross-sectional clinical study. Tertiary hospital. We studied 299 MUO and 122 MHO Chinese women matched on body mass index. Metabolically healthy obese was defined as obesity with no more than one metabolic abnormality. Diagnosis of PCOS was based on the revised Rotterdam criteria. Each subject underwent physical examination, laboratory evaluation, and gynecologic ultrasound for a diagnosis of PCOS or metabolic syndrome (MetS). Prevalence of PCOS was calculated in both groups. Insulin resistance was determined by homeostasis model assessment of insulin resistance or by the insulin sensitivity index derived from Bergman's minimal model. Fat distribution was measured with computerized tomography scan. Prevalence of PCOS and its components did not differ between MUO and BMI-matched MHO groups (67.89% and 66.96%, respectively). In logistic regression analysis, MetS did not predict the presence of PCOS after adjusting for confounding factors. The MHO group had lower visceral adipose tissue, relatively higher insulin sensitivity, and better β-cell function, compared with those in the MUO group; but there were no significant differences in sex hormones (except for free T and sex hormone-binding globulin) and ultrasound manifestations between MHO and MUO women. For the first time, our findings suggest that MetS does not add additional risk for PCOS. In addition, we found that both MUO and MHO are associated with insulin resistance to some extent.