Association of hypovitaminosis D with metabolic disturbances in polycystic ovary syndrome

Abstract

Objectives: Women with polycystic ovary syndrome (PCOS) frequently suffer from metabolic disturbances, in particular from insulin resistance. Accumulating evidence suggests that vitamin D deficiency may contribute to the development of metabolic syndrome (MS). Hence, the aim of our study was to investigate the association of 25(OH)D levels and the components of the MS in PCOS women. Methods: 25(OH)D levels were measured by means of ELISA in 206 women affected by PCOS. Metabolic, endocrine, and anthropometric measurements and oral glucose tolerance tests were performed. Results: The prevalence of insufficient 25(OH)D levels (!30 ng/ml) was 72.8% in women with PCOS. PCOS women with MS had lower 25(OH)D levels than PCOS women without these features (17.3 vs 25.8 ng/ml respectively; P!0.05). In multivariate regression analysis including 25(OH)D, season, body mass index (BMI), and age, 25(OH)D and BMI were independent predictors of homeostatic model assessment-insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI; P!0.05 for all). In binary logistic regression analyses, 25(OH)D (odds ratio, OR 0.86, PZ0.019) and BMI (OR 1.28, P!0.001) were independent predictors of MS in PCOS women. We found significantly negative correlations of 25(OH)D levels with BMI, waist circumference, waist-to-hip ratio, systolic and diastolic blood pressure, fasting and stimulated glucose, area under the glucose response curve, fasting insulin, HOMA-IR, HOMA-b, triglycerides, and quotient total cholesterol/high-density lipoprotein (HDL) and positive correlations of 25(OH)D levels with QUICKI and HDL (P!0.05 for all). Conclusion: We demonstrate that low 25(OH)D levels are associated with features of MS in PCOS women. Large intervention trials are warranted to evaluate the effect of vitamin D supplementation on metabolic disturbances in PCOS women.

Highly prevalence of vitamin D deficiency among Brazilian women of reproductive age

“…Furthermore, other authors have suggested that vitamin D deficiency is associated with PCOS only among obese women (30,31). Moreover, another study found that hypovitaminosis D was associated with insulin resistance, regardless of the patient's body mass index (32). Unfortunately, we were unable to evaluate the relationships of obesity and/or body mass index with hypovitaminosis D among women with PCOS, as these data were not included in the records that we retrospectively analyzed.…”

MECHANISMS IN ENDOCRINOLOGY: Thyroid and polycystic ovary syndrome

“…Associations between the low 25(OH)D levels and features of metabolic syndrome (77), and between VDR and vitamin D-related polymorphisms and metabolic and endocrine parameters, but not with PCOS susceptibility per se, have been shown (70). However, in PCOS women from Iran, an association of VDR ApaI polymorphisms with PCOS susceptibility was found (40).…”

The role of vitamin D in metabolic disturbances in polycystic ovary syndrome: a systematic review

“…Twelve studies had an observational design (18,19,20,21,22,23,24,25,26,27,28,29), employing a crosssectional or case-control design, with vitamin D status as one of the preliminary outcomes. A summary of these studies is given in Table 1.…”

“…The studies included premenopausal women (14-50 years) of various ethnicities, with the number of participants ranging from 45 to 400. Different stratifications were used: seven studies compared PCOS women with controls (19,20,22,23,24,27,28), three studies compared lean vs obese PCOS women (18,21,26), one study compared PCOS women with and without the metabolic syndrome (25), and one study solely included PCOS women (29). Large differences were found in the prevalence of vitamin D deficiency (defined as serum 25OHD levels !50 nmol/l), varying from 37% in a study carried out in Italy (21) to 72% in a study carried out in Scotland (19).…”