Metabolic syndrome and its components in premenopausal and postmenopausal women: a comprehensive systematic review and meta-analysis on observational studies

Objectives: To perform a meta-analysis on the global prevalence of metabolic syndrome (MetS) in postmenopausal women. The meta-analysis also sought to measure the relationship menopause status has with MetS and its components. Methods: The Web of Science, Medline, PubMed, Scopus, Embase, CINAHL, DOAJ, and Google Scholar were all searched using the relevant keywords. Articles published during the period 2004 to 2017 that met our inclusion criteria and reported the prevalence of MetS among premenopausal and postmenopausal women were included. In the presence of heterogeneity, random-effects models were used to pool the prevalence and odds ratios (ORs), as measures of association in cross-sectional and comparative cross-sectional studies, respectively. Results: The prevalence of MetS among postmenopausal women (119 studies [n = 95,115]) and the OR comparing the prevalence of MetS among postmenopausal and premenopausal women (23 studies [n = 66,801]) were pooled separately. The pooled prevalence of MetS among postmenopausal women was found to be 37.17% (95% confidence interval [CI] 35.00%-39.31%), but varied from 13.60% (95% CI 13.55%-13.64%) to 46.00% (95% CI 1.90%-90.09%), depending upon the diagnostic criteria used. The overall pooled OR for MetS in postmenopausal women, compared with premenopausal women, was OR 3.54 (95% CI 2.92-4.30), but this ranged from OR 2.74 (95% CI 1.32-5.66) to OR 5.03 (95% CI 2.25-11.22), depending upon the criteria used. Furthermore, the odds of high fasting blood sugar (OR 3.51, 95% CI 2.11-5.83), low high-density lipoprotein cholesterol (OR 1.45, 95% CI 1.03-2.03), high blood pressure (OR 3.95, 95% CI 2.01-7.78), high triglycerides (OR 3.2, 95% CI 2.37-4.31), and high waist circumference (OR 2.75, 95% CI 1.80-4.21) were all found to be higher in postmenopausal women than in premenopausal women. Conclusions: The prevalence of MetS is relatively high in postmenopausal women and was more prevalent among postmenopausal than premenopausal women. Menopausal hormone therapy should be used with caution in patients with MetS, as its safety has not yet been evaluated among MetS patients and meticulous evaluation of each individual patient before starting MHT is needed.