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Introduction: Women with polycystic ovary syndrome (PCOS) have increased risk of metabolic syndrome. The relative contribution of clinical, demographic or biochemical factors to metabolic syndrome in PCOS is not known. A literature search was conducted in MEDLINE, CINAHL, EMBASE and clinical trial registries. Of 4530 studies reviewed, 59 were included in the systematic review and 27 in the meta-analysis and meta-regression. In good and fair quality studies, women with PCOS had an overall increased prevalence of metabolic syndrome (odds ratio, OR 3.35, 95% confidence interval, CI 2.44, 4.59). Increased prevalence of metabolic syndrome occurred in overweight or obese women with PCOS (OR 1.88, 95% 1.16, 3.04) but not in lean women (OR 1.45, 95% CI 0.35, 6.12). In metaregression analyses, the markers of metabolic syndrome diagnostic criteria (waist circumference, high-density lipoprotein cholesterol, triglyceride, blood pressure), BMI, glucose tolerance (2-hr oral glucose tolerance test) and surrogate markers of insulin resistance (HOMA-IR) but not markers of reproductive dysfunction (sex hormone binding globulin, testosterone, PCOS phenotypes) contributed significantly to the heterogeneity in the prevalence of metabolic syndrome. Women with PCOS have increased risk of metabolic syndrome which was associated with obesity and metabolic features but not with indices of hyperandrogenism.

Xin Sun and colleagues discuss the development of real world evidence in Chinese healthcare and propose strategies to improve its quality and usefulness

Objective: To compare the effects of metformin, rosiglitazone, and their combination in obese polycystic ovary syndrome (PCOS) patients with insulin resistance. Design: Prospective randomized controlled trail. Setting: Tertiary teaching hospital. Patient(s): Obese Chinese women (body mass index [BMI] R25 kg/m 2 ) with insulin resistance who fulfilled the Rotterdam criteria of PCOS. Intervention(s): In group 1, 68 patients administered metformin (1,500 mg/day); in group 2, 67 patients administered rosiglitazone (4 mg/day); in group 3, 69 patients administered metformin (1,000 mg/day) and rosiglitazone (4 mg/day) for 6 months, all with the same diet and regular exercise lifestyle recommendation. Main Outcome Measure(s): Average menstrual interval, anthropometric measurements, androgen-related parameters, and metabolic features of insulin, carbohydrates, and lipids, with intention-to-treat analysis. Result(s): The baseline parameters showed no statistically significant differences. After the 6-month treatment, most participants showed an improved menstrual pattern. There were statistically significant decreases in acne scores, weight, BMI, waist circumference, waist-to-hip ratio, and serum testosterone. The metabolic indexes of insulin, carbohydrates, and lipids were improved obviously compared with the baseline in each group. Among the three groups, the patients administered 1,500 mg/day metformin experienced greater reductions in weight. However, the rosiglitazone users (alone or combined with metformin) showed a more notable decline in total cholesterol and triglyceride levels. Conclusion(s):Considering the benefits of metformin on weight loss, high-dose metformin (1,500 mg/day) along with lifestyle modification should be recommended for obese, insulin-resistant women with PCOS. Rosiglitazone alone or combined with lowdosage metformin plus lifestyle modification should be considered for the women with abnormal lipid profiles.