Metabolic syndrome in polycystic ovary syndrome: a systematic review, meta-analysis and meta-regression.

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 meta-regression 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.

Does the risk of metabolic disorders increase among women with polycystic ovary morphology? A population-based study.

STUDY QUESTION: Is polycystic ovary morphology (PCOM) associated with metabolic syndrome (MS), insulin resistance (IR) and dyslipidemia? SUMMARY ANSWER: No associations between PCOM and metabolic disorders were found. WHAT IS KNOWN ALREADY: Polycystic ovary morphology has a prevalence of 21-63% in healthy women of reproductive age. Results of studies focusing on metabolic abnormalities among females with PCOM, are insufficient and controversial. STUDY DESIGN, SIZE, DURATION: This was a cross-sectional population-based study from five provinces in Iran. A standard questionnaire was filled out during face-to-face interviews and clinical examinations were done. All study subjects were invited to undergo blood sampling and ultrasonographic assessment. PARTICIPANTS/MATERIALS, SETTING, METHODS: From a total of 1772 women, 809 participants met the inclusion criteria of this study, i.e. non-pregnant, reproductive-age, ovulatory, normo-androgenic, without hyperprolactinemia/thyroid dysfunction. Participants were divided into two groups; 126 women with PCOM on ultrasound assessment, as the case and 683 women with normal ovarian morphology, as the control groups. The association of PCOM with MS, IR and dyslipidemia were analyzed using logistic regression models, adjusted for confounding variables. MAIN RESULTS AND THE ROLE OF CHANCE: Mean systolic blood pressure (SBP), high density lipoprotein (HDL) and androstenedione (A4) serum levels of women with PCOM were significantly higher than in the normal group (P = 0.04, 0.05 and 0.008, respectively). Comparison between groups revealed dyslipidemia to be higher among controls. However the results of logistic regression models, after adjustment for possible confounding variables showed that there were no significant association between prevalence of MS, IR and dyslipidemia with PCOM. LIMITATIONS, REASONS FOR CAUTION: Due to the study being cross-sectional, blood samples were collected only once thus we did not measure serum concentrations of progesterone in the luteal phase, which determines subclinical anovulation. Moreover, due to budget limitations, enzyme immunoassay was used for androgenic measurements while mass spectrometry-based assays have been known as the gold standard method. However we defined our groups very strictly to overcome these limitations. WIDER IMPLICATIONS OF THE FINDINGS: It seems that biochemical and metabolic characteristics of women with PCOM do not differ significantly to those of normal women. To clarify the association between PCOM and metabolic characteristics, longitudinal studies investigating long-term metabolic disorders among women with PCOM are highly recommended. STUDY FUNDING/COMPETING INTEREST: No external funding was used for this study. No conflicts of interest are declared.