Vitamin D predictors in polycystic ovary syndrome: A meta-analysis.
Eur J Clin Invest. 2017 Aug 10. Epub 2017 Aug 10. PMID: 28795765
BACKGROUND: The aim of this meta-analysis was to examine differences and predictors of serum 25-hydroxyvitamin D concentrations in women with polycystic ovary syndrome (PCOS) compared with non-PCOS controls matched for body mass index.
MATERIALS AND METHODS: Three databases were searched (2003-2015) to retrieve studies that evaluated serum 25-hydroxyvitamin D in PCOS women and controls. Meta-regression analysis was performed with anthropometric and metabolic/endocrine parameters as covariates.
RESULTS: Fourteen studies that included 2,262 women (1,150 PCOS patients/1,162 controls) were eligible. Serum 25-hydroxyvitamin D, follicle stimulating hormone and sex hormone-binding globulin were significantly lower in PCOS patients than controls. Homeostatic model assessment-insulin resistance index, serum insulin, total cholesterol, triglycerides, low-density lipoprotein cholesterol, luteinizing hormone and testosterone were significantly higher in PCOS patients compared to controls. Meta-regression analysis demonstrated significant effects of waist-to-hip ratio and glucose in PCOS women (β = -1.60, 95% CI: -2.30 to -0.90, P=0.003; β = 0.20, 95% CI: 0.80 to 0.32, P=0.004, respectively) and controls (β = -2.36, 95% CI: -3.38 to -1.33, P=0.003; β = 0.11, 95% CI: 0.00 to 0.21, P=0.05, respectively) and of total calcium and luteinizing hormone in PCOS cases (β = 2.43, 95% CI: 1.67 to 3.19, P=0.005; β = -0.37, 95% CI: -0.68 to -0.06, P=0.03, respectively).
CONCLUSIONS: Serum 25-hydroxyvitamin D may be predicted positively by serum calcium and negatively by luteinizing hormone in women with PCOS, and negatively by waist-to-hip ratio and positively by fasting glucose in both PCOS and non-PCOS women, independently of the presence of obesity. This article is protected by copyright. All rights reserved.