The effect of Vitamin D supplementation on hormonal and glycaemic profile of patients with PCOS: A meta-analysis of randomised trials

PCOS and vitamin D: a clinical appraisal

PURPOSE

Polycystic ovary syndrome (PCOS) is the most common endocrine-reproductive disease linked not just to infertility but also to serious comorbidities. There is a reported association between low vitamin D levels and multiple health conditions including PCOS. This narrative review aims to analyze the role of vitamin D in PCOS development, use of the vitamin D in the treatment of PCOS, and the molecular basis of these observations.

METHODS

A Medline and PubMed research was performed, during the years 1990-2023, using a combination of keywords on such topic. According to the author's evaluation and target, papers were identified and included for a narrative review.

RESULTS

There are associations between lower levels of vitamin D and PCOS, as well as with insulin resistance, metabolic syndrome, hyperandrogenemia, metabolic and endocrine disorders as well as the onset of oxidative stress and pro-inflammatory milieu, in PCOS women.

CONCLUSION

Vitamin D has a role in pathologic changes linked to PCOS. Molecular and clinical investigations which give new information about the role of vitamin D in the development of PCOS and related endocrine and metabolic disturbance are further needed.

The Effect of Vitamin D Supplementation on Lipid Profiles: an Umbrella Review of Meta-Analyses

According to published meta-analyses, vitamin D exerts different beneficial effects in preventing and controlling risk factors associated with noncommunicable chronic diseases; however, the results are still conflicting. The purpose of this umbrella meta-analysis was to investigate the effect of vitamin D supplementation on low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, total cholesterol (TC), and triglyceride (TG) as components of the lipid profile. PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews were systematically searched for meta-analyses of randomized controlled trials. The umbrella meta-analysis followed the PRISMA guidelines. The random-effects model was employed to estimate the overall effect size (ES). Overall, 25 meta-analyses were included. In the standardized mean difference analysis, vitamin D significantly decreased TG (ES: -0.15; 95% CI: -0.23, -0.08; P ≤ 0.001) and TC levels (ES: -0.17; 95% CI: -0.23, -0.11; P ≤ 0.001) and increased HDL levels (ES: 0.08; 95% CI: 0.01, 0.15; P = 0.025). In the weighted mean difference analysis, vitamin D significantly decreased only TG levels (ES: -4.63 mg/dL; 95% CI: -7.70, -1.57; P = 0.003). The present study supports that vitamin D supplementation could be considered a beneficial adjuvant therapy in managing lipid profile levels, especially in individuals with vitamin D deficiency. This systematic review was registered in PROSPERO as CRD42022306334.

Vitamin D: Can Gender Medicine Have a Role?

This narrative review aims to shed light on the role of gender differences, on the biological and molecular functions in the main pathological mechanisms that recognize the role of vitamin D. Vitamin D deficiency is widespread worldwide, but it is still very controversial whether the amount of vitamin D taken daily is actually the only problem related to its biological functions. Currently, the plasma concentration of 25-hydroxyvitamin D represents the only indicator of the circulating blood quota. The concept is that the biological function of vitamin D is not only linked to its circulating levels, but it is hypothesized that its biological functions depend, above all, on its total bioavailability. In particular, vitamin D circulates for the most part linked to albumin and vitamin D binding protein (DBP), which depend on various pathological conditions and physiologically, above all, the function of the latter is regulated by estrogens, glucocorticoids, and inflammatory cytokines. During her life, women undergo various changes in the hormonal and sexual sphere concerning menarche, possible pregnancies, and breastfeeding but also the use of contraceptives and, finally, the transition from the period of fertility to menopause. Each of these phases presents specific needs and, consequently, sometimes also specific criticalities. Studies on young women have shown that vitamin D deficiency is present in 58 to 91% of cases. Obesity, metabolic disorders, and variation in estrogen contraction may affect vitamin D deficiency due to the decreased bioavailability from dietary sources due to deposition in body fat compartments.

1,25-Dihydroxyvitamin D inhibits hepatic diacyglycerol accumulation and ameliorates metabolic dysfunction in polycystic ovary syndrome rat models

Introduction: We aimed to evaluate the influence of 1,25-dihydroxyvitamin D (1,25(OH)2D) on metabolic dysfunction and elucidate its underlying mechanism using a rat model of polycystic ovary syndrome (PCOS).

Methods: Twenty-four Sprague-Dawley rats were randomly divided into four groups: control group (CON, 2 ml/kg of oral 0.5% CMC), 1,25VD group (oral 0.5% CMC and 2.5 ug/kg intraperitoneal 1,25(OH)2D), PCOS group (1 mg/kg oral letrozole), PCOS+1,25VD group (1 mg/kg oral letrozole orally 2.5 ug/kg intraperitoneal 1,25(OH)2D). The treatments were administered for 8 weeks. Body weight, estrus cycle, insulin tolerance, and oral glucose tolerance of the rats in the different groups were assessed. The rats were euthanized at the 8th weeks, and plasma, ovarian, and liver samples were collected and analyzed. The hepatic lipid profile was characterized using HPLC/MRM.

Results: Letrozole-induced PCOS rats exhibited increased weight, insulin resistance, postprandial glucose abnormalities, and dyslipidemia. Compared with the PCOS group rats, the PCOS+1,25VD group rats showed reduced body weight, increased sensitivity to insulin, decreased postprandial glucose, and elevated levels of high-density lipoprotein cholesterol. Moreover, abnormally increased liver concentrations of total diacylglycerol (DG) and DG species in the PCOS rats were reversed by treatment with 1,25(OH)2D. Additionally, hepatic DG and insulin sensitivity were correlated.

Conclusion: 1,25(OH)2D inhibited hepatic DG accumulation and ameliorated metabolic dysfunction in PCOS rat models.

Effects of nutrition on metabolic and endocrine outcomes in women with polycystic ovary syndrome: an umbrella review of meta-analyses of randomized controlled trials

CONTEXT

Numerous meta-analyses have been conducted on the effects of nutritional interventions on various health outcomes in women with polycystic ovary syndrome (PCOS). However, the strength of the evidence and its clinical significance are unclear.

OBJECTIVE

This umbrella review aimed to summarize the effects of nutritional interventions on women with PCOS and assess the strength of the evidence.

DATA SOURCES

PubMed, Scopus, and Web of Science were searched from inception until March 17, 2021.

DATA EXTRACTION

Meta-analyses of randomized clinical trials (RCTs) that examined the impact of dietary modifications or supplementations on women with PCOS were selected. Data extraction, quality assessments of the meta-analyses, and evaluation of the strength of the evidence were conducted independently by 2 investigators and confirmed by a third.

DATA ANALYSIS

Twenty-eight RCT meta-analyses were included, reporting 40 different outcomes. Lower carbohydrate, Dietary Approaches to Stop Hypertension, or lower glycemic index/load diets in women with PCOS significantly improved some anthropometric and metabolic characteristics (with very low to low certainty). Probiotics/synbiotics reduced fasting plasma glucose, fasting insulin (FI), and homeostasis model assessment-estimated insulin resistance (HOMA-IR) (with moderate to high certainty). Curcumin supplementation decreased fasting plasma glucose, FI, and HOMA-IR (with moderate certainty). Fish oil supplementation decreased FI and HOMA-IR, and omega-3 reduced triglycerides (with moderate certainty). There were also improvements in FI after taking vitamin D or inositol supplements (with moderate certainty). Supplementation with fish oil increased adiponectin (with high certainty), and probiotics/synbiotics reduced total testosterone (with moderate certainty). In subfertile women with PCOS, inositol increased the ovulation rates (with moderate certainty).

CONCLUSION

There was no high-certainty evidence that diets alone in women with PCOS improved health or reproductive outcomes. Supplementation with vitamin D, probiotics/synbiotics, omega-3, inositol, and curcumin showed favorable effects on some metabolic outcomes. Probiotics/synbiotics possibly reduces total testosterone, and inositol stimulates ovulation in women with PCOS.

REGISTRATION

PROSPERO registration no. CRD42021251496.

Deficiency and Insufficiency of Vitamin D in Women of Childbearing Age: A Systematic Review and Meta-analysis

OBJECTIVE

 To estimate the prevalence of inadequate vitamin D level and its associated factors for women of childbearing age in Brazil.

METHODS

 A systematic review was conducted (last updated May 2020). Meta-analyses were performed using the inverse-variance for fixed models with summary proportion calculation by Freeman-Tukey double arcsine. Reporting and methodological quality were assessed using the Joanna Briggs Institute tool for prevalence studies.

RESULTS

 Our review identified 31 studies, comprising 4,006 participants. All the studies had at least one weakness, mainly due to the use of convenience sampling and small sample size. The overall prevalence of vitamin D deficiency, insufficiency, and both deficiency and insufficiency were 35% (confidence interval, 95%CI: 34-37%), 42% (95%CI: 41-44%), and 72% (95%CI: 71-74%), respectively.

CONCLUSION

 Although the magnitude of the prevalence of inadequate levels of vitamin D is uncertain, the evidence suggests that presence of vitamin D deficiency or insufficiency in women of reproductive age can cause moderate to severe problems.

Effect of calcium and vitamin D supplementation on the clinical, hormonal, and metabolic profile in non-obese women with polycystic ovary syndrome

BACKGROUND

In this study, we investigated the effect of calcium and vitamin D (Ca/Vit D) supplementation on the clinical, hormonal, and metabolic profile of patients with low vitamin D levels. In addition, we investigated the effect of Ca/Vit D supplementation on asymmetric dimethylarginine (ADMA) level in patients with polycystic ovary syndrome (PCOS).

METHODS

In total, 75 patients aged 19-35 years, with a normal body mass index and a diagnosis of PCOS and Vit D deficiency/insufficiency, were included in the study. Patients received 50,000 IU of vitamin D3 once a week for 8 weeks. Afterward, 2500 mg calcium carbonate equivalent to 1000 mg calcium ion and 9.68 mg cholecalciferol equivalent to 880 IU vitamin D3 were administered orally as a maintenance treatment once a day.

RESULTS

The mean age of the patients was 21.7 ± 3.5. After Ca/Vit D supplementation, Vit D levels significantly increased compared to baseline (8.6 ng/ml) levels. An increase in SHBG levels (p < 0.001), a decrease in total testosterone, FAI (p = 0.042), and ADMA levels (p < 0.001) were observed in the first and third months compared to the onset. Significant improvement compared to baseline was observed in menstrual irregularity and median mFG score.

CONCLUSION

Ca/Vit D supplementation can improve PCOS symptoms such as menstrual dysfunction, hirsutism, and hyperandrogenism. It may be effective in reducing the risk of cardiovascular disease in patients with PCOS later in life by decreasing ADMA levels, which is an indicator of endothelial dysfunction.

The effectiveness of coenzyme Q10, vitamin E, inositols, and vitamin D in improving the endocrine and metabolic profiles in women with polycystic ovary syndrome: a network Meta-analysis

OBJECTIVE

This research evaluated the efficacy of oral nutritional agents including CoQ10, vitamin E, inositols and vitamin D on androgen-associated hormones, glycolipid metabolism and body weight in women with PCOS.

METHOD

A multi-database search was performed from inception to December 2020. Using multi-variate random effects method, a NMA was conducted by synthesizing data pooled from RCTs. It was registered with PROSPERO (registration number CRD42021230292).

RESULTS

Twenty-three RCTs and 1291 participants were included. Based on NMA, CoQ10, vitamin E, CoQ10 combined with vitamin E, and inositols were successful in decreasing TT as compared with PA; vitamin E was superior to other agents. Vitamin E and inositols were successful in increasing SHBG levels; inositols were stronger than vitamin E. CoQ10 alone or combined with vitamin E, and inositols were successful in decreasing HOMA-IR. Inositols had the best results among included nutraceuticals to ameliorate HOMA-IR, FBG, FINS, TG, TC, and LDL-C and correlated to improvements in BMI. There was no significant difference between the CoQ10 or vitamin E group and the PA group in ameliorating lipid metabolism, and vitamin D had no positive effects in ameliorating hyperandrogenism, BMI, glycolipid metabolism profiles compared with PA.

CONCLUSION

For women with PCOS, inositols supplementation have some certain advantages in increasing SHBG and improving glycolipid metabolism when compared with nutraceuticals like CoQ10, vitamin E, vitamin D. Besides, vitamin E may be a better option in reducing TT and increasing SHBG. CoQ10 alone or combined with vitamin E can be helpful in decreasing HOMA-IR as well.

Vitamin D deficiency effects on cardiovascular parameters in women with polycystic ovary syndrome: A retrospective, cross-sectional study

PURPOSE

Polycystic ovary syndrome (PCOS) is associated with vitamin D deficiency (25-hydroxyvitamin D (25(OH)D), and both are associated with increased cardiovascular risk; therefore, the combination of PCOS and moderate vitamin D deficiency may exacerbate the cardiovascular and metabolic characteristics in women with PCOS. This study sought to address this question.

METHODS

In this retrospective, cross-sectional study, demographic and metabolic data from women aged 18-40 years from the Qatar Biobank (QBB) (78 diagnosed with PCOS, 641 controls) was analyzed.

RESULTS

Moderate vitamin D deficiency was seen in both normal and PCOS cohorts irrespective of body mass index (BMI) stratification into normal, overweight and obese. Significant differences in free androgen index (FAI) and high density lipoproteins (HDL) (p < 0.05) were seen in PCOS irrespective of BMI, though insulin resistance and increased C-reactive protein (CRP) (p < 0.05) were seen only in obese PCOS subjects; however, there was no correlation (Pearson coefficient) of any these parameters with vitamin D for women with or without PCOS, nor when vitamin D deficiency was compared to vitamin D insufficiency (above and below 20 ng/mL, respectively) between the normal and PCOS groups.

CONCLUSION

Moderate vitamin D deficiency did not associate with nor exacerbate insulin resistance, androgen levels, inflammation or cardiovascular risk indices in women with PCOS, suggesting that a prospective study on vitamin D deficiency to confirm non-causality is required.

Effects of vitamin D supplementation on metabolic parameters of women with polycystic ovary syndrome: a meta-analysis of randomized controlled trials

OBJECTIVE

The purpose of this meta-analysis was to evaluate the effects of vitamin D supplementation on metabolic parameters of women with polycystic ovary syndrome (PCOS).

METHODS

We performed a literature search of databases and identified randomized controlled trials (RCTs) published prior to December 2019. A meta-analysis was conducted using RevMan 5.3 and Stata 12.0 software. We compared the effects of vitamin D supplementation alone to the administration of placebos on metabolic parameters of PCOS women with vitamin D deficiency.

RESULTS

Ten articles of RCTs were included and analyzed in this meta-analysis, which included a total of 520 PCOS women. Our meta-analysis results showed no significant effects of vitamin D supplementation on BMI (p = .43), systolic blood pressure (p = .05), diastolic blood pressure (p = .87), fasting insulin concentration (p = .86), HOMA-IR (p = .47), HDL-C (p = .76), LDL-C (p = .23) and triglyceride (p = .77). Both low dose vitamin D supplementation (<4000 IU/day) and high dose vitamin D supplementation (≥4000 IU/day) were found to significantly decreased the fasting glucose concentration (p = .01, p = .001, respectively). Vitamin D supplementation significantly decreased total cholesterol concentration (p = .03).

CONCLUSIONS

The results of this meta-analysis suggested that vitamin D supplementation decreases fasting glucose concentration and total cholesterol concentration in PCOS women with vitamin D deficiency.

The Effect of Vitamin D Supplementation on Blood Lipids in Patients with Polycystic Ovary Syndrome: A Meta-Analysis of Randomized Controlled Trials

PURPOSE

Studies have found that vitamin D supplementation may improve blood lipids in patients with polycystic ovary syndrome, but the results are controversial, so this study will further analyze the effect of vitamin D supplementation on blood lipids in patients with polycystic ovary syndrome.

METHODS

PubMed, Embase, Cochrane Library, CNKI, and Wanfang databases were searched up to May 2020, to identify randomized controlled trials of the effect of vitamin D supplementation on blood lipids in patients with polycystic ovary syndrome. The Cochrane risk of bias tool was applied to assess the risk of bias, and RevMan5.3 software was used for statistical analysis.

RESULTS

Ten studies were included in this study, including 543 subjects. The results of the meta-analysis showed that, compared with placebo, vitamin D supplementation can significantly reduce total cholesterol level (WMD = -11.32, 95% CI = [-14.51, -8.41], P < 0.00001), low-density lipoprotein cholesterol level (WMD = -4.83, 95% CI = [-7.52, -2.14], P=0.0004), and triglyceride level (WMD = -8.23, 95% CI = [-13.08, -3.38], P=0.0009, but the effect on high-density lipoprotein cholesterol level is not statistically significant (WMD = -0.32, 95%CI = [-1.24, 0.60], P=0.50).

CONCLUSION

Vitamin D supplementation can significantly reduce total cholesterol, low-density lipoprotein cholesterol, and triglycerides in patients with polycystic ovary syndrome. However, it has no significant effect on high-density lipoprotein cholesterol.

Influence of vitamin D supplementation on lipid levels in polycystic ovary syndrome patients: a meta-analysis of randomized controlled trials

Objective

Observational studies have shown that circulating vitamin D (VitD) deficiency is associated with atherogenic lipid patterns among polycystic ovary syndrome (PCOS) patients. However, interventional studies have shown inconsistent results. The aim of this meta-analysis was to investigate how VitD supplementation influences lipid indices in PCOS patients.

Methods

The authors searched four electronic databases through August 2019 to identify randomized controlled trials (RCTs) that assessed the effect of VitD intervention on serum lipids among PCOS patients. Mean differences were generated for statistical evaluation.

Results

We included eight studies and performed nine comparisons across 467 participants. VitD supplementation reduced serum triglyceride levels (−11.88 mg/dL; 95% confidence interval [CI]: −17.03 to −6.73), total cholesterol (−9.09 mg/dL; 95% CI: −14.90 to −3.29), low-density lipoprotein cholesterol (−5.22 mg/dL; 95% CI: −10.32 to −0.13), and very-low-density lipoprotein cholesterol (−2.43 mg/dL; 95% CI: −3.69 to −1.17) compared with no VitD supplementation. However, high-density lipoprotein cholesterol levels showed no differences with or without VitD supplementation (−0.39 mg/dL; 95% CI: −1.39 to 0.61).

Conclusions

VitD supplementation improved serum lipid levels among PCOS patients, but serum high-density lipoprotein cholesterol levels were not changed. VitD intervention might benefit PCOS patients who are at high risk of an atherogenic lipid profile.

The Association between Vitamin D and Anti-Müllerian Hormone: A Systematic Review and Meta-Analysis

Accumulating evidence from animal and human studies indicates a role for vitamin D in female reproductive physiology, and numerous clinical studies have suggested its potential benefit for various aspects of human reproduction. Anti-Müllerian hormone (AMH) is an ovarian biomarker that plays an important role in folliculogenesis. It is the most sensitive ovarian reserve marker and is widely used clinically in reproductive medicine. While initial studies have suggested that vitamin D may be associated with ovarian reserve markers, including AMH, evidence has been conflicting. Currently, there is considerable debate in the field whether vitamin D has the capacity to influence ovarian reserve, as indicated by the AMH level. The current systematic review aims to evaluate and summarize the available evidence regarding the relationship between vitamin D and AMH. In total, 18 observational studies and 6 interventional studies were included in this systematic review. Cross-sectional studies have reported largely discrepant findings regarding an association between serum vitamin D and AMH levels, which are likely due to the heterogeneity in study populations, as well as the apparently complex relationship that may exist between vitamin D and AMH. However, meta-analysis of interventional studies performed herein that examined the effects of vitamin D supplementation on serum AMH levels indicates a cause-effect relationship between vitamin D and AMH, the direction of which appears to depend on a woman’s ovulatory status. Serum AMH was significantly decreased following vitamin D supplementation in polycystic ovarian syndrome (PCOS) women (standardized mean difference (SMD) −0.53, 95% CI −0.91 to −0.15, p < 0.007), while it was significantly increased following vitamin D supplementation in ovulatory women without PCOS (SMD 0.49, 95% CI 0.17 to 0.80, p = 0.003). In conclusion, the results of this systematic review demonstrate that the relationship between vitamin D and AMH is a complex one, and large, randomized trials of vitamin D supplementation focusing on different vitamin D status ranges are necessary to gain more insight into the nature of this relationship and the potential benefit of vitamin D to female reproduction in general.

Vitamin D Supplementation Ameliorates Metabolic Dysfunction in Patients with PCOS: A SystematicReview of RCTs and Insight into the Underlying Mechanism

OBJECTIVE

Evidence suggests that vitamin D deficiency correlated with metabolic disorders in women with polycystic ovary syndrome (PCOS). We conducted this systematic review and meta-analysis to evaluate the impact of vitamin D supplementation alone on glucose, lipid, and androgen parameters and inflammation biomarkers in women with PCOS.

METHODS

Literature research was conducted in Pubmed, Embase, Web of Science, Clinical Trials, and Cochrane Library to identify relevant randomized controlled trials (RCTs) up to March 2020. The effect of vitamin D supplementation alone on women with PCOS was compared with administration of placebo. The systematic review and meta-analysis protocol was registered in the International Prospective Register of Systematic Reviews (Prospero) as number CRD42020157444.

RESULTS

Thirteen randomized controlled trials with 824 patients in total were included. Serum FPG, fasting insulin, HOMA-IR, and VLDL-C were significantly decreased in the vitamin D group versus placebo. Vitamin D supplementation group also showed a significantly elevated level of QUICKI. No significant impact was seen on serum triglyceride, total-C, LDL-C, HDL-C, total testosterone, DHEAS, SHBG, or hs-CRP. Subgroup analysis demonstrated that oral vitamin D intake had significantly decreased serum triglyceride and total-C level in women with PCOS who have vitamin D deficiency (serum vitamin D < 20 ng/ml).

CONCLUSION

The findings of the present meta-analysis indicate that vitamin D supplementation exerted favorable effects among women with PCOS on glucose metabolism and lipid metabolism, especially in vitamin D deficient women, but had no significant effect on the androgenic profile or inflammation status.

Vitamin D Levels in Women with Polycystic Ovary Syndrome: A Population-Based Study

Background: Conflicting evidence supports a role for vitamin D in women with reproductive disorders such as polycystic ovary syndrome (PCOS) but studies on large, unselected populations have been lacking. Methods: We conducted a general population-based study from the prospective Northern Finland Birth Cohort 1966 (NFBC1966). Serum 25-hydroksyvitamin D (25(OH)D) levels were evaluated in women with self-reported PCOS (n = 280) versus non-symptomatic controls (n = 1573) at the age of 31 with wide range of endocrine and metabolic confounders. Results: The levels of 25(OH)D were similar among women with and without self-reported PCOS (50.35 vs. 48.30 nmol/L, p = 0.051). Women with self-reported PCOS presented with a higher body mass index (BMI), increased insulin resistance, and low-grade inflammation and testosterone levels compared to controls. The adjusted linear regression model showed a positive association between total 25(OH)D levels in self-reported PCOS (β = 2.46, 95% confidence interval (CI) 0.84 to 4.08, p = 0.003). The result remained after adjustment for BMI, testosterone, homeostatic model assessment of insulin resistance (HOMA-IR), and high-sensitivity C-reactive protein (hs-CRP) levels. Conclusion: In this population-based setting, PCOS was associated with higher vitamin D levels when adjusting for confounding factors, without distinct beneficial effects on metabolic derangements.

Vitamin D and cardiometabolic disorders: a review of current evidence, genetic determinants and pathomechanisms

Vitamin D deficiency has been implicated in the pathophysiology of cardiometabolic disorders including obesity, type 2 diabetes mellitus, cardiovascular diseases and polycystic ovary syndrome. Despite a large number of experimental and observational studies supporting a role for vitamin D in these pathologies, randomized controlled trials have reported little to no effect of vitamin D supplementation in the prevention or treatment of these disorders, although some results remain ambiguous. Polymorphisms in genes related to vitamin D metabolism, particularly in the vitamin D receptor and binding protein and the metabolizing enzyme 1-α-hydroxylase, have emerged as potential contributors to these divergent results. It is now becoming increasingly recognized that the effects and potential benefits of vitamin D supplementation may vary by several factors including vitamin D deficiency status, ethnicity and/or the presence of genetic variants, which affect individual responses to supplementation. However, these factors have seldom been explored in the available literature. Future trials should consider inter-individual differences and, in particular, should aim to clarify whether certain subgroups of individuals may benefit from vitamin D supplementation in the context of cardiometabolic health.

A Randomized, Controlled Trial of Vitamin D Supplementation on Cardiovascular Risk Factors, Hormones, and Liver Markers in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) increases the risk of metabolic syndrome and non-alcoholic-fatty-liver disease (NAFLD). Vitamin D supplementation may exert positive effects on liver biochemistry in patients with NAFLD; however, its effects on PCOS are unknown. This randomized, double-blind, placebo-controlled study explored the effect of vitamin D supplementation on cardiovascular risk factors (high-sensitivity C-reactive protein (hs-CRP), weight, body mass index (BMI), lipid profile, glucose levels, insulin levels, the homeostatic model assessment-insulin resistance (HOMA-IR), hormones (free androgen index (FAI), testosterone, sex hormone binding globulin (SHBG), and liver markers (alanine aminotransferase (ALT), hyaluronic acid (HA), N-terminal pro-peptide of type III procollagen (PIIINP), tissue inhibitor of metallo-proteinases-1 (TIMP-1), and the enhanced liver fibrosis (ELF) score). Forty women with PCOS were recruited and randomized to vitamin D (3200 IU) or placebo daily for 3 months. All outcomes were measured at baseline and 3 months follow-up (FU). Greater increases in vitamin D levels were shown in the supplementation group (vitamin D, baseline: 25.6 ± 11.4 nmol/L, FU: 90.4 ± 19.5 nmol/L vs. placebo, baseline: 30.9 ± 11.1 nmol/L, FU: 47.6 ± 20.5 nmol/L, p < 0.001). Between groups comparisons (% baseline change) revealed significant differences in ALT (p = 0.042) and a weak effect indicating a greater reduction in the HOMA-IR in the vitamin D group (p = 0.051). No further between group differences were seen in other cardiovascular risk factor, liver markers, or hormones. This study supports beneficial effects of vitamin D supplementation on liver markers and modest improvements in insulin sensitivity in vitamin D deficient women with PCOS.

Pharmacological and surgical treatment of nonreproductive outcomes in polycystic ovary syndrome: An overview of systematic reviews

BACKGROUND

Polycystic ovary syndrome (PCOS) affects up to 13% women and is associated with significant complications. The quality of evidence supporting the recommendations on treatment of nonreproductive outcomes in PCOS is unknown.

OBJECTIVE

To summarize and appraise the methodological quality of systematic reviews and meta-analyses evaluating pharmacological and surgical treatments for nonreproductive outcomes in PCOS.

METHODS

A literature search from MEDLINE, EMBASE, CINAHL PLUS and PROSPERO was performed from inception until 15th of September 2017. Article selection, data extraction and quality appraisal of included reviews were performed in duplicate. A narrative synthesis of the findings was conducted.

RESULTS

This overview included 31 reviews. The quality was low for 7 (23%), moderate for sixteen (52%) and high for 8 reviews (26%). Two reviews assessed psychological outcomes. Metformin improved anthropometric (7 of 10 reviews), metabolic (4 of 14 reviews) and endocrine outcomes (3 of twelve reviews). Thiazolidinediones improved metabolic (2 of 5 reviews) and endocrine outcomes (one of 5 reviews) but worsened weight gain (5 of 5 reviews). Combined oral contraceptive pill (COCP) improved clinical hyperandrogenism (2 of 2 reviews). Statins improved lipid profile (3 of 3 reviews) and testosterone level (2 of 3 reviews). There was no conclusive evidence from included systematic reviews regarding the use of other interventions.

CONCLUSIONS

There is reliable evidence regarding the use of metformin for anthropometric outcomes and COCPs for hyperandrogenism in women with PCOS but not for other interventions. There is significant gap in knowledge regarding the management of psychological outcomes in women with PCOS which needs further evaluation.

Effects of vitamin D supplementation on metabolic and endocrine parameters in PCOS: a randomized-controlled trial

PURPOSE

Vitamin D status may be associated with insulin resistance and other key features of polycystic ovary syndrome (PCOS), but data from preliminary randomized controlled trials (RCTs) are conflicting. Therefore, we aimed to investigate the effects of vitamin D supplementation on plasma glucose area under the curve (AUCgluc, primary outcome measure) and on other metabolic and endocrine parameters (secondary outcome measures).

METHODS

This study was a single-center, double-blind, randomized placebo-controlled trial conducted between December 2011 and July 2017 at the Medical University of Graz, Austria. One-hundred and eighty women with PCOS and 25-hydroxyvitamin D [25(OH)D] concentrations < 75 nmol/L were randomized in a 2:1 ratio to either receive 20,000 IU of cholecalciferol weekly or placebo over 24 weeks. Primary outcome was the between-group difference in AUCgluc at study end while adjusting for baseline values.

RESULTS

In total, 123 participants completed the study [age 25.9 ± 4.7 years; BMI 27.5 ± 7.3 kg/m²; baseline 25(OH)D 48.8 ± 16.9 nmol/L, baseline fasting glucose 84 ± 8 mg/dL]. Vitamin D supplementation lead to a significant increase in 25(OH)D [mean treatment effect 33.4 nmol/L; 95% confidence interval (CI) 24.5 to 42.2; p < 0.001] but had no significant effect on AUCgluc (mean treatment effect - 9.19; 95% CI - 21.40 to 3.02; p = 0.139). Regarding secondary outcome measures, we observed a significant decrease in plasma glucose at 60 min during oral glucose tolerance test (mean treatment effect - 10.2 mg/dL; 95% CI - 20.2 to - 0.3; p = 0.045).

CONCLUSIONS

Vitamin D supplementation had no significant effect on metabolic and endocrine parameters in PCOS with the exception of a reduced plasma glucose during OGTT.