Nitric oxide (NO) levels in patients with polycystic ovary syndrome (PCOS): a meta-analysis

Objective The pathogenesis of polycystic ovarian syndrome (PCOS) remains unclear, but is known to be related to increased insulin resistance, diabetes, obesity, oxidative stress, inflammation, and cardiovascular disease. No meta-analyses have examined whether PCOS is associated with nitric oxide (NO). Therefore, we aimed to evaluate the association between serum/plasma nitrite levels and PCOS. Methods We performed a meta-analysis. To identify eligible original articles, we searched online computerized databases, including EMBASE, Medline, and Web of Science. The characteristics of each single study, as well as the standard mean difference (SMD) with corresponding confidence intervals (CIs), were calculated and subgroup analysis was performed to examine heterogeneity. Results We included 12 articles with 16 studies and a total of 895 patients were included in the meta-analysis. We found a significant association between PCOS and serum or plasma nitrite levels, with a pooled SMD of −0.61 (95% CI: −1.05 to −0.16). The final pooled data were determined by the random effects model because significant high heterogeneity ( I2 = 89%) was found. Conclusions Our meta-analysis shows that decreased serum or plasma nitrite levels are associated with PCOS. The pathogenesis of PCOS may be due to endothelial dysfunction; however, further research to confirm this possibility is required.

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Circulating Adipokine Levels in Nonobese Women With Polycystic Ovary Syndrome and in Nonobese Control Women: A Systematic Review and Meta-Analysis

Frontiers in Endocrinology ◽

10.3389/fendo.2020.537809 ◽

2021 ◽

Vol 11 ◽

Author(s):

Kainan Lin ◽

Xiaoting Sun ◽

Xiao Wang ◽

Hanchu Wang ◽

Xia Chen

Keyword(s):

Polycystic Ovary Syndrome ◽

Web Of Science ◽

Polycystic Ovary ◽

Meta Analysis ◽

Scientific Evidence ◽

Healthy Controls ◽

Ovary Syndrome ◽

Eligibility Criteria ◽

Standardized Mean Difference ◽

Circulating Levels

Levels of circulating adipokines in nonobese polycystic ovary syndrome (PCOS) patients have been reported in many studies. However, the results are inconsistent. The aim of this meta-analysis is to assess whether the levels of circulating adipokines are changed in nonobese PCOS relative to nonobese healthy controls. To identify eligible studies, a literature research was performed in the PubMed, Embase, and Web of Science databases without restricting by region, journal, or language. A total of 81 studies met the eligibility criteria. The meta-analysis showed that the circulating level of adiponectin (standardized mean difference [SMD]: -0.95; 95% CI: -1.36 to -0.53) was significantly decreased in nonobese PCOS patients. In contrast, the circulating levels of chemerin (SMD: 1.13; 95% CI: 0.08 to 2.18), leptin (SMD: 0.47; 95% CI: 0.13 to 0.81), resistin (SMD: 0.45; 95% CI: 0.03 to 0.88), and visfatin (SMD: 1.38; 95% CI: 0.68 to 2.09) were significantly increased in nonobese PCOS patients. There were no significant changes in the circulating levels of apelin (SMD: 0.32; 95% CI: -1.34 to 1.99), irisin (SMD: 1.01; 95% CI: -0.68 to 2.70), omentin (SMD: -0.37; 95% CI: -1.05 to 0.31), or vaspin (SMD: 0.09; 95% CI: -0.14 to 0.32). Thus, scientific evidence suggests that the circulating adipokine levels are altered in nonobese PCOS patients compared to nonobese healthy controls. Therefore, independent of the degree of obesity, dysregulated circulating adipokine levels might play important roles in the occurrence and development of PCOS.

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Circulating adipokines in non-obese PCOS patients: a systematic review and meta-analysis

10.1101/2020.10.11.20210716 ◽

2020 ◽

Author(s):

Kainan Lin ◽

Xiaoting Sun ◽

Xiao Wang ◽

Hanchu Wang ◽

Xia Chen

Keyword(s):

Systematic Review ◽

Polycystic Ovary Syndrome ◽

Web Of Science ◽

Polycystic Ovary ◽

Meta Analysis ◽

Scientific Evidence ◽

Inclusion Criteria ◽

Ovary Syndrome ◽

Literature Research ◽

Circulating Levels

AbstractConcentrations of circulating adipokines in non-obese polycystic ovary syndrome (PCOS) patients had been reported in many researches, however, these results were conflicting. The aim of this meta-analysis was to assess whether the levels of circulating adipokines were changed in non-obese PCOS. To identify eligible studies, literature research was performed in the database of PubMed, Embase, Web of Science without the restriction of region, publication or language. Of the total studies found, only 81 met the inclusion criteria. The meta-analysis showed that circulating levels of adiponectin [-0.95 (95% CI, −1.36 to −0.53)] decreased statistically in non-obese PCOS women. On the contrary, circulating levels of chemerin [1.13 (95% CI, 0.08 to 2.18)], leptin [0.47 (95% CI, 0.13 to 0.81)], resistin [0.45 (95% CI, 0.03 to 0.88)] and visfatin [1.38 (95% CI, 0.68 to 2.09)] increased significantly in non-obese PCOS females. Besides, there was no statistically significant change in the circulating levels of apelin [0.32 (95% CI, −1.34 to 1.99), irisin [1.01(95% CI, −0.68 to 2.70), omentin [-0.37(95% CI, −1.05 to 0.31)] and vaspin [0.09(95% CI, −0.14 to 0.32)] in non-obese PCOS patients. Scientific evidence suggested that the levels of circulating adipokines altered in non-obese PCOS patients compared with controls. Independent of the degree of obesity, the abnormal change of circulating adipokines levels might play an important role in the occurrence and development of PCOS.

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To share or not to share data: how valid are trials evaluating first-line ovulation induction for polycystic ovary syndrome?

Human Reproduction Update ◽

10.1093/humupd/dmaa031 ◽

2020 ◽

Vol 26 (6) ◽

pp. 929-941

Author(s):

Esmee M Bordewijk ◽

Rui Wang ◽

Madelon van Wely ◽

Michael F Costello ◽

Robert J Norman ◽

...

Keyword(s):

Polycystic Ovary Syndrome ◽

Ovulation Induction ◽

Polycystic Ovary ◽

Meta Analysis ◽

Risk Of Bias ◽

Methodological Issues ◽

First Line ◽

Ovary Syndrome ◽

Inconsistency Rate ◽

Meta Analyses

Abstract BACKGROUND In our recent individual participant data (IPD) meta-analysis evaluating the effectiveness of first-line ovulation induction for polycystic ovary syndrome (PCOS), IPD were only available from 20 studies of 53 randomized controlled trials (RCTs). We noticed that the summary effect sizes of meta-analyses of RCTs without IPD sharing were different from those of RCTs with IPD sharing. Granting access to IPD for secondary analysis has implications for promoting fair and transparent conduct of RCTs. It is, however, still common for authors to choose to withhold IPD, limiting the impact of and confidence in the results of RCTs and systematic reviews based on aggregate data. OBJECTIVE AND RATIONALE We performed a meta-epidemiologic study to elucidate if RCTs without IPD sharing have lower quality and more methodological issues than those with IPD sharing in an IPD meta-analysis evaluating first-line ovulation induction for PCOS. SEARCH METHODS We included RCTs identified for the IPD meta-analysis. We dichotomized RCTs according to whether they provided IPD (shared group) or not (non-shared group) in the IPD meta-analysis. We restricted RCTs to full-text published trials written in English. We assessed and compared RCTs in the shared and non-shared groups on the following criteria: Risk of Bias (RoB 2.0), GRADE approach, adequacy of trial registration; description of statistical methods and reproducibility of univariable statistical analysis; excessive similarity or difference in baseline characteristics that is not compatible with chance; and other miscellaneous methodological issues. OUTCOMES In total, 45 trials (8697 women) were included in this study. IPD were available from 17 RCTs and 28 trials were categorized as the non-shared IPD group. Pooled risk rates obtained from the shared and non-shared groups were different. Overall low risk of bias was associated with 13/17 (76%) of shared RCTs versus 7/28 (25%) of non-shared RCTs. For RCTs that started recruitment after 1 July 2005, adequate trial registration was found in 3/9 (33%) of shared IPD RCTs versus 0/16 (0%) in non-shared RCTs. In total, 7/17 (41%) of shared RCTs and 19/28 (68%) of non-shared RCTs had issues with the statistical methods described. The median (range) of inconsistency rate per study, between reported and reproduced analyses for baseline variables, was 0% (0–92%) (6 RCTs applicable) in the shared group and 54% (0–100%) (13 RCTs applicable) in the non-shared group. The median (range) of inconsistency rate of univariable statistical results for the outcome(s) per study was 0% (0–63%) (14 RCTs applicable) in the shared group and 44% (0–100%) (24 RCTs applicable) in the non-shared group. The distributions of simulation-generated P-values from comparisons of baseline continuous variables between intervention and control arms suggested that RCTs in the shared group are likely to be consistent with properly conducted randomization (P = 0.163), whereas this was not the case for the RCTs in the non-shared group (P = 4.535 × 10−8). WIDER IMPLICATIONS IPD meta-analysis on evaluating first-line ovulation induction for PCOS preserves validity and generates more accurate estimates of risk than meta-analyses using aggregate data, which enables more transparent assessments of benefits and risks. The availability of IPD and the willingness to share these data may be a good indicator of quality, methodological soundness and integrity of RCTs when they are being considered for inclusion in systematic reviews and meta-analyses.

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The prevalence of polycystic ovary syndrome in adolescents: A systematic review and meta-analysis

International Journal of Reproductive BioMedicine ◽

10.18502/ijrm.v17i8.4818 ◽

2019 ◽

Cited By ~ 2

Author(s):

Marzieh Saei Ghare Naz ◽

Fahimeh Ramezani Tehrani ◽

Hamid Alavi Majd ◽

Fazlollah Ahmadi ◽

Giti Ozgoli ◽

...

Keyword(s):

Systematic Review ◽

Polycystic Ovary Syndrome ◽

Polycystic Ovarian Syndrome ◽

Polycystic Ovary ◽

Meta Analysis ◽

Qualitative Assessment ◽

Ovary Syndrome ◽

The World ◽

Ovarian Syndrome ◽

Different Parts

Background: Polycystic ovarian syndrome is an endocrine disorder with many complications. This syndrome is a growing concern among adolescents around the world, with varying reports of its prevalence in different parts of the world. Objective: This study aimed to determine the prevalence of polycystic ovary syndrome in adolescents by a systematic review and meta-analysis. Materials and Methods: In this study, a search for published articles with an English language limitation and without a time limit was done in different databases (Scopus, PubMed, and Web of Science, Emabse and Cochrane) in January 2019. The 12 studies that met the criteria for entering a qualitative assessment scale of 5 and higher were subjected to systematic review and meta-analysis. Egger and Begg’s tests were used to check the publication bias. Data were analyzed with STATA software, version 11.1. Results: Twelve studies were included for meta-analysis. The total number of participants in the study was 149,477. The average quality score of all studies was 8.67 (range: 5–10). The prevalence of polycystic ovarian syndrome in adolescents based on the Rotterdam criteria was 11.04% (95% CI: 6.84–16.09%), based on the National Institute of Health criteria, it was 3.39% (95% CI: 0.28–9.54%), and based on Androgen Excess and Polycystic Ovary Syndrome Society, it was 8.03% (95% CI: 6.24–10.01%). Conclusion: The result of this study showed that there is a variation in the prevalence of PCOS in adolescents based on different criteria; we suggest more community-based studies among adolescences in different parts of the world.

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A polycystás ovarium szindróma szövődményeinek prevenciója, kezelése és a kórkép bizonyítékokon alapuló, interdiszciplináris ellátásának fontossága

Orvosi Hetilap ◽

10.1556/650.2015.30254 ◽

2015 ◽

Vol 156 (50) ◽

pp. 2018-2026 ◽

Cited By ~ 1

Author(s):

Sándor Gődény ◽

Orsolya Karola Csenteri

Keyword(s):

Cardiovascular Health ◽

Polycystic Ovary ◽

Serum Insulin ◽

Health Gain ◽

Interdisciplinary Approach ◽

Cardiovascular Complications ◽

Ovary Syndrome ◽

Relevant Evidence ◽

Meta Analyses ◽

Ovarian Syndrome

Polycystic ovary syndrome is the most common hormonal and metabolic disorder likely to affect women. The syndrome is often associated with obesity, hyperinsulinemia and adversely affects endocrine, metabolic, and cardiovascular health. The complex feature of the syndrome requires an interdisciplinary approach to treatment, where cooperation of paediatrician, internist, gynaecologist, endocrinologist, dermatologist, psychologist and oncologist is essential. The prevention and the treatment should be based on the best available evidence. This should include physical examination, laboratory tests for hormones, serum insulin, glucose, lipids, in addition patient’s preferences should be considered, too. To maximise health gain of polycystic ovarian syndrome, adequate, effective, efficient and safe treatment is necessary. This article summarises the highest available evidence provided by meta-analyses and systematic reviews of the prevention of metabolic and cardiovascular complications of the syndrome, and discusses the relevant evidence published in the literature. Orv. Hetil., 2015, 156(50), 2018–2026.

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Effect of Diet on Insulin Resistance in Polycystic Ovary Syndrome

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgaa425 ◽

2020 ◽

Vol 105 (10) ◽

pp. 3346-3360 ◽

Cited By ~ 3

Author(s):

Yujie Shang ◽

Huifang Zhou ◽

Minghui Hu ◽

Hua Feng

Keyword(s):

Systematic Review ◽

Insulin Resistance ◽

Body Composition ◽

Polycystic Ovary Syndrome ◽

Polycystic Ovary ◽

Meta Analysis ◽

Dietary Advice ◽

Model Assessment ◽

Ovary Syndrome ◽

Meta Analyses

Abstract Objective The effect of diet on insulin resistance (IR) in polycystic ovary syndrome (PCOS) is controversial. Thus, we conducted this systematic review and meta-analysis to evaluate whether diet could reduce IR in women with PCOS while providing optimal and precise nutrition advice for clinical practice. Design The search was conducted in 8 databases through June 30, 2019. The systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A random-effects model was adopted to calculate the overall effects. Results A total of 19 trials (1193 participants) were included. The analysis showed that diet was significantly related to improvements in IR and body composition (eg, homeostasis model assessment of insulin resistance, fasting insulin, fasting plasma glucose, body mass index [BMI], weight, and waist circumference) in PCOS patients. The Dietary Approaches to Stop Hypertension diet and calorie-restricted diets might be the optimal choices for reducing IR and improving body composition, respectively, in the PCOS population. Additionally, the effects were associated with the course of treatment. The longer the duration, the greater the improvement was. Compared with metformin, diet was also advantageous for weight loss (including BMI and weight) and had the same effects on insulin regulation. Conclusion Overall, our findings suggest that diet is an effective, acceptable and safe intervention for relieving IR, and professional dietary advice should be offered to all PCOS patients.

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Non-coding RNAs in polycystic ovary syndrome: a systematic review and meta-analysis

Reproductive Biology and Endocrinology ◽

10.1186/s12958-020-00687-9 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Liangshan Mu ◽

Xiaoting Sun ◽

Mixue Tu ◽

Dan Zhang

Keyword(s):

Systematic Review ◽

Polycystic Ovary Syndrome ◽

Web Of Science ◽

Polycystic Ovary ◽

Meta Analysis ◽

Circular Rnas ◽

Small Interfering Rnas ◽

Ovary Syndrome ◽

Diagnostic Biomarkers ◽

Non Coding Rnas

Abstract Background Genetic, environmental and epigenetical factors may play important roles in the pathogenesis of polycystic ovary syndrome (PCOS), however the etiology of PCOS remains unclear. Studies indicated that non-coding RNAs (ncRNAs) were involved in the occurrence and development of PCOS. Thus, we aim to perform a systematic review and meta-analysis to investigate the presence and dysregulated expression of ncRNAs in human PCOS. Methods We searched in PubMed, Medline, Web of Science and Embase until July 2019 and summarized all eligible publications focusing on microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and small interfering RNAs (siRNAs) in PCOS. Results Sixty-seven articles were included in our systematic review and 9 articles were included in meta-analysis. There is little overlap between studies when comparing miRNA profiles. Sensitivity analysis showed that the expression of miR-93 was upregulated in PCOS patients (WMD 0.75, P < 0.00001), without heterogeneity among remaining studies (I2 = 0%). Conclusion A large number of ncRNAs with altered levels were observed in plasma, serum, follicular fluid, granulosa cells or other issues from PCOS patients. Aberrant ncRNAs expression in PCOS may lead to aberrant steroidogenesis, adipocyte dysfunction, altered ovarian cell proliferation and/or apoptosis and have the potential to be used as diagnostic biomarkers.

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