Uric acid participating in female reproductive disorders: a review

Association of serum uric acid with women's ovarian reserve: observational study and Mendelian randomization analyses

OBJECTIVE

To investigate the association between serum uric acid and women's ovarian reserve.

DESIGN

Retrospective observational study and Mendelian randomization study.

SETTING

University-affiliated in vitro fertilization center.

PATIENTS

Observational analyses were undertaken using data from 8,257 women with infertility who finished their first in vitro fertilization treatments between May 2017 and December 2021. Mendelian randomization analyses were based on genome-wide association summary statistics from several biobanks of predominantly European ancestries.

INTERVENTIONS

Observational study involved testing log2 transformed serum uric acid levels (for linear, negative regression, and logistic regression analyses); original uric acid levels (for nonlinear association analyses). Mendelian randomization study involved testing genetically predicted uric acid levels.

MAIN OUTCOME MEASURES

Biomarkers including antimüllerian hormone, basal antral follicle count, follicle-stimulating hormone, luteinizing hormone, ratio of follicle-stimulating hormone to luteinizing hormone, estradiol; indices of ovarian response to stimulation including poor ovarian response according to different criteria and oocyte yield.

RESULTS

In retrospective observational study, all ovarian reserve-related outcomes demonstrated significant differences across serum uric acid quartiles. A two-fold uric acid increase was associated with increased antimüllerian hormone (adjusted β = 0.69; 95% confidence interval [CI], 0.43-0.95), antral follicle count (adjusted incidence rate ratio = 1.10, 95% CI, 1.05-1.14), luteinizing hormone (adjusted β = 0.53, 95% CI, 0.28-0.78), decreased risks of Bologna poor ovarian response (adjusted odds ratio = 0.97; 95% CI, 0.95-0.99) and groups 2-4 Poseidon poor ovarian response (group 2: 0.63, 0.56-0.71; group 3: 0.71, 0.65-0.78; group 4: 0.50, 0.46-0.55), whereas an increased risk of group 1 (1.26, 1.13-1.41). Nonlinear analyses showed a common inflection point at 320-340 μmol/L of uric acid. Interactions between uric acid and antimüllerian hormone and antral follicle count were presented in association with oocyte yield. Mendelian randomization results suggested a significant association between genetically predicted uric acid levels and antimüllerian hormone levels (β = 0.08; 95% CI, 0.04-0.12) but none for uric acid in relation to polycystic ovarian syndrome or other related hormones.

CONCLUSION

Higher uric acid levels were associated with better ovarian reserve and increased levels of antimüllerian hormone albeit an increased risk of unexpected poor ovarian response.

Decoding connections in the European population: serum uric acid, sex hormone-binding globulin, total testosterone, estradiol, and female infertility - advanced bidirectional and mediative Mendelian randomization

Background

Despite observational links between serum uric acid (SUA), sex hormone-related phenotypes, and female infertility, the causality behind these associations remains uncertain.

Objective

This study utilizes Bidirectional Two-Sample and Mediation Mendelian Randomization to explore the causal relationships and mediation effects of sex hormone-binding globulin (SHBG), total testosterone (TT), and estradiol on these associations.

Methods

We analyzed single-nucleotide polymorphisms (SNPs) associated with SUA and sex hormone levels using data from large-scale GWAS of European populations. Female infertility data were sourced from 6,481 cases and 75,450 controls in the FinnGen Consortium. We employed methods including Inverse Variance Weighted (IVW), Weighted Median, and MR-Egger regression to assess causality.

Results

We found that elevated SUA levels causally increase the risk of female infertility (IVW OR: 1.13, P=0.047). Elevated SUA levels significantly decrease SHBG levels (β=-0.261; P=2.177e-04), with SHBG mediating 27.93% of the effect of SUA on infertility (OR=0.854; 95%CI, 0.793-0.920; P=2.853e-05). Additionally, elevated TT levels, which were associated with decreased SUA levels (β=-0.127), showed an indirect effect on infertility mediated by SUA (β=-0.0187; 95% CI, -0.041 to -0.003; P=0.046).

Conclusion

Our findings demonstrate causal links between high SUA and increased risk of female infertility mediated by hormonal factors such as SHBG and TT. These insights suggest new avenues for infertility treatment and highlight the need for further research into these mechanisms.

Creating machine learning models that interpretably link systemic inflammatory index, sex steroid hormones, and dietary antioxidants to identify gout using the SHAP (SHapley Additive exPlanations) method

Background

The relationship between systemic inflammatory index (SII), sex steroid hormones, dietary antioxidants (DA), and gout has not been determined. We aim to develop a reliable and interpretable machine learning (ML) model that links SII, sex steroid hormones, and DA to gout identification.

Methods

The dataset we used to study the relationship between SII, sex steroid hormones, DA, and gout was from the National Health and Nutrition Examination Survey (NHANES). Six ML models were developed to identify gout by SII, sex steroid hormones, and DA. The seven performance discriminative features of each model were summarized, and the eXtreme Gradient Boosting (XGBoost) model with the best overall performance was selected to identify gout. We used the SHapley Additive exPlanation (SHAP) method to explain the XGBoost model and its decision-making process.

Results

An initial survey of 20,146 participants resulted in 8,550 being included in the study. Selecting the best performing XGBoost model associated with SII, sex steroid hormones, and DA to identify gout (male: AUC: 0.795, 95% CI: 0.746- 0.843, accuracy: 98.7%; female: AUC: 0.822, 95% CI: 0.754- 0.883, accuracy: 99.2%). In the male group, The SHAP values showed that the lower feature values of lutein + zeaxanthin (LZ), vitamin C (VitC), lycopene, zinc, total testosterone (TT), vitamin E (VitE), and vitamin A (VitA), the greater the positive effect on the model output. In the female group, SHAP values showed that lower feature values of E2, zinc, lycopene, LZ, TT, and selenium had a greater positive effect on model output.

Conclusion

The interpretable XGBoost model demonstrated accuracy, efficiency, and robustness in identifying associations between SII, sex steroid hormones, DA, and gout in participants. Decreased TT in males and decreased E2 in females may be associated with gout, and increased DA intake and decreased SII may reduce the potential risk of gout.

Relationship between serum uric acid in early pregnancy and gestational diabetes mellitus: a prospective cohort study

PURPOSE

The association between serum uric acid (UA) and gestational diabetes mellitus (GDM) was still unclear. Serum UA levels in pregnancy differed from that in non-pregnancy. This study aimed to investigate the changes of serum UA in early pregnancy, and to explore the association of serum UA with the risk of GDM.

METHODS

A prospective double-center study including 873 singleton pregnant women was conducted in Beijing, China since 2019 (clinical trial number: NCT03246295). Seventy-eight healthy non-pregnant women were selected to compare the changes of biomarkers in pregnancy. Spearman correlation and logistic regression analysis were performed to measure the relationship between serum UA in early pregnancy and GDM.

RESULTS

The incidence of GDM in our cohort was 20.27%(177/873). Compared with non-pregnant women, serum UA and creatinine decreased significantly during early pregnancy. Serum UA concentration in early pregnancy was significantly higher in GDM women than that in normal glucose tolerance (NGT) women [217.0(192.9, 272.0) μmol/l vs. 201.9(176.0, 232.0) μmol/l, p < 0.001]. After adjusted for confounding factors, elevated serum UA remained as an independent risk factor for GDM. The risk of GDM increased when serum UA was above 240 μmol/l (adjusted OR 1.964, 95% CI 1.296-2.977, p < 0.001), and stronger relationships between serum UA and GDM were observed in pregnant women aged over 35 years old and preBMI ≥ 24 kg/m2.

CONCLUSION

The normal range of serum UA and creatinine in pregnant women were lower than those in non-pregnant women. It is essential to monitor serum UA concentrations since early pregnancy to alert and prevent GDM, especially in older and heavier pregnant women.

CLINICAL TRIAL NUMBER

NCT03246295.

Serum uric acid did not affect embryonic and pregnancy outcomes in women without PCOS during IVF procedures

Objectives

Serum uric acid (UA) levels are associated with many systemic diseases. A previous study confirmed the association between high serum uric acid levels and poor prognosis of in vitro fertilization (IVF) treatment in polycystic ovary syndrome (PCOS) patients. This study aimed to explore the correlation between serum uric acid levels and reproductive outcomes in patients without PCOS.

Methods

A retrospective study that included 1057 patients who underwent pre-implantation genetic testing for monogenic disorders (PGT-M) treatment from January 2013 to December 2020 was conducted. The study population was further divided into 3 groups according to serum UA levels: the ≤250 μmol/L group, the 251-360 μmol/L group, and the >360 μmol/L group. The controlled ovarian hyperstimulation (COH) treatment outcomes, embryonic treatment outcomes and pregnancy outcomes of the first frozen embryo transfer (FET) cycle were compared among groups. Multivariable linear regression and binary regression were applied to detect the association between IVF outcomes and serum uric acid levels.

Results

The number of retrieved oocytes, fertilization rate, viable embryo rate, blastocyst formation rate and euploid rate were not associated with serum uric acid levels. The mature oocyte rate was negatively correlated with serum uric acid levels. The pregnancy outcomes of the first FET cycle were also not associated with serum uric acid levels. After adjustment for BMI, the perinatal outcomes were not associated with serum uric acid levels.

Conclusion

IVF treatment outcomes were not associated with serum uric acid levels in patients without PCOS.

Prevalence of Hyperuricemia and Associated Cardiovascular Risk Factors in Elite Athletes Practicing Different Sporting Disciplines: A Cross-Sectional Study

Uricemia has been identified as an independent risk factor for cardiovascular disease. In the general population, hyperuricemia is associated with hypertension, endothelial dysfunction, and other cardiovascular risk (CVR) factors. Our aim was to explore the prevalence of hyperuricemia among Olympic athletes, evaluating the influence of sporting discipline and its correlation with CVR factors. We enrolled 1173 Olympic athletes classified into four disciplines: power, skill, endurance, and mixed. Clinical, anthropometric data, and complete blood test results were collected. Hyperuricemia was present in 4.4% of athletes, 0.3% were hypertensive, 11.7% had high-normal blood pressure values, 0.2% were diabetic, 1.2%. glucose intolerance, 8.2% active smokers, and 3% were obese. Males had a higher prevalence of hyperuricemia (5.3%) than females (3.4%) with no significant differences between different sporting disciplines (male, p = 0.412; female p = 0.561). Males with fat mass >22% presented higher uricemia (5.8 ± 1 vs. 5.3 ± 1 mg/dL, p = 0.010) like hypertensive athletes (6.5 ± 0.3 vs. 5.3 ± 1 mg/dL, p = 0.031), those with high-normal blood pressure (5.13 ± 1 vs. 4.76 ± 1.1 mg/dL, p = 0.0004) and those with glucose intolerance (6 ± 0.8 vs. 5.3 ± 1 mg/dL, p = 0.066). The study provides a comprehensive evaluation of hyperuricemia among Olympic athletes, revealing a modest prevalence, lower than in the general population. However, aggregation of multiple CVR factors could synergistically elevate the risk profile, even in a population assumed to be at low risk. Therefore, uric acid levels should be monitored as part of the CVR assessment in athletes.

The association of hyperuricemia and maternal and fetal outcomes among pregnant women: a meta-analysis

OBJECTIVE

This meta-analysis aimed to investigate the relationship between hyperuricemia and maternal and neonatal complications in pregnant women.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library from the databases' inception to August 12, 2022. We included studies that reported results on the association between hyperuricemia and maternal and fetal outcomes among pregnant women. Using the random-effects model, the pooled odds ratio (OR) with 95% confidence intervals (CIs) was calculated for each outcome analysis.

RESULTS

A total of 7 studies, including 8104 participants, were included. The pooled OR for pregnancy-induced hypertension (PIH) was 2.61 [0.26, 26.56] (z = 0.81, p = .4165; I² = 96.3%). The pooled OR for preterm birth was 2.52 [1.92, 3.30] (z = 6.64, p < .0001; I² = 0%). The pooled OR for low birth weight (LBW) was 3.44 [2.52, 4.70] (z = 7.77, p < .0001; I² = 0%). The pooled OR for small gestational age (SGA) was 1.81 [0.60, 5.46] (z = 1.06, p = .2912; I² = 88.6%).

CONCLUSION

Results of this meta-analysis indicate a positive relationship between hyperuricemia and PIH, preterm birth, LBW, and SGA in pregnant women.

Excessively Increased Skeletal Muscle Mass of the Bilateral Lower Limbs is Associated with Hyperuricemia in Females with Polycystic Ovarian Syndrome

This study is aimed at evaluating the correlation between the skeletal muscle mass index (SMI) of different body parts and hyperuricemia in females with polycystic ovary syndrome (PCOS), thus, providing scientific guidance on lifestyle self-management for patients with PCOS. The cross-sectional study included 171 patients with PCOS, which were divided into two distinct sub-groups based on the presence or absence of hyperuricemia. Anthropometric and serological characteristics of the population with PCOS focusing on skeletal muscle mass were conducted. PCOS patients with hyperuricemia had significantly greater SMI in different body parts. Further binary logistic regression analysis revealed that SMI of the bilateral lower limbs was positively associated with hyperuricemia with an adjusted odds ratio (95% confidence interval) of 1.235 (1.103 - 1.384), p < 0.001. The optimal cut-off value of SMI of the bilateral lower limbs in predicting hyperuricemia was 5.11 (Youden index = 0.490). Combined with the mean value of SMI in the bilateral upper limbs, the safe range of SMI of the bilateral lower limbs in patients with PCOS was calculated as 3.64 - 5.11, with the sensitivity and negative predictive values being 83.9% and 65.1%, respectively. Excessively increased SMI of the bilateral lower limbs was correlated with hyperuricemia in patients with PCOS.

Elevated serum uric acid is associated with infertility in women living in America

Excessive uric acid levels may affect several organs and systems in the body. There is limited evidence of the effects of high serum uric acid levels on the female reproductive system. This study used the National Health and Nutrition Examination Survey (NHANES) database to explore the relationship between serum uric acid and female infertility. This cross-sectional study included a total of 2197 eligible subjects using data from NHANES 2013-March 2020 pre-pandemic data. Self-reported infertility (ever experiencing an inability to conceive after 12 months of trying to become pregnant) was the main outcome. Logistic regression models and restricted cubic spline were used to analyze the relationship between serum uric acid and female infertility, and stratified analysis was carried out. A total of 295 women self-reported infertility (13.43%). The median uric acid level for all study subjects was 4.4 mg/dL (interquartile range [IQR]: 3.7, 5.1). Serum uric acid levels were higher in the infertility group than in the control group (4.7 mg/dL [IQR: 4.0, 5.3] vs. 4.4 mg/dL [IQR: 3.7, 5.1], P < 0.001). After adjusting for age, race, marital status, smoking, alcohol, history of pregnancy, history of diabetes, history of hypertension, fasting glucose, total cholesterol, creatinine in refrigerated serum, low-density lipoprotein cholesterol, direct high-density lipoprotein cholesterol, glycohemoglobin, and body mass index confounders, women with serum uric acid levels at Q3 (4.4-5.1 mg/dL) had a 73% (odds ratio [OR] = 1.73, 95% confidence interval [CI] 1.18, 2.54, P = 0.005) higher risk of infertility, and women with uric acid levels at Q4 (5.1-18.0 mg/dL) had an 83% (OR = 1.83, 95% CI 1.22, 2.75, P = 0.003) increased risk of infertility compared to women at Q1 (1.6-3.7 mg/dL). The restricted cubic spline also showed that when serum uric acid levels exceeded the reference value, the risk of infertility gradually increased. We also performed a sensitivity analysis based on the complete dataset and found that the results were robust. Higher serum uric acid levels were significantly associated with an increased risk of female infertility. Women planning a pregnancy should have increased serum uric acid monitoring.

Distinct metabolic signatures in blood plasma of bisphenol A-exposed women with polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is a complicated endocrinopathy with an unclear etiology that afflicts fertility status in women. Although the underlying causes and pathophysiology of PCOS are not completely understood, it is suspected to be driven by environmental factors as well as genetic and epigenetic factors. Bisphenol A (BPA) is a weak estrogenic endocrine disruptor known to cause adverse reproductive outcomes in women. A growing relevance supports the notion that BPA may contribute to PCOS pathogenesis. Due to the indeterminate molecular mechanisms of BPA in PCOS endocrinopathy, we sought liquid chromatography with tandem mass spectrometry (LC-MS/MS), a metabolomics strategy that could generate a metabolic signature based on urinary BPA levels of PCOS and healthy individuals. Towards this, we examined urinary BPA levels in PCOS and healthy women by ELISA and performed univariate and chemometric analysis to distinguish metabolic patterns among high and low BPA in PCOS and healthy females, followed by pathway and biomarker analysis employing MetaboAnalyst 5.0. Our findings indicated aberrant levels of certain steroids, sphingolipids, and others, implying considerable disturbances in steroid hormone biosynthesis, linoleic, linolenic, sphingolipid metabolism, and various other pathways across target groups in comparison to healthy women with low BPA levels. Collectively, our findings provide insight into metabolic signatures of BPA-exposed PCOS women, which can potentially improve management strategies and precision medicine.

Implications of serum uric acid for female infertility: results from the national health and nutrition examination survey, 2013-2020

BACKGROUND

There is limited concrete evidence connecting serum uric acid levels to female infertility. Therefore, this study aimed to find out if serum uric acid levels are independently related to female infertility.

METHODS

From the National Health and Nutrition Examination Survey (NHANES) 2013-2020, a total sample of 5872 chosen female participants between the ages of 18 and 49 were identified for this cross-sectional study. The serum uric acid levels (mg/dL) of each participant were tested, and the reproductive health questionnaire was used to evaluate each subject's reproductive status. Both in the analyses of the full sample and each subgroup, logistic regression models were used to evaluate the relationship between the two variables. A stratified multivariate logistic regression model was used to perform the subgroup analysis based on serum uric acid levels.

RESULTS

Infertility was found in 649 (11.1%) of the 5,872 female adults in this study, with greater mean serum uric acid levels (4.7 mg/dL vs. 4.5 mg/dL). Serum uric acid levels were associated with infertility in both the initial and adjusted models. According to multivariate logistic regression, the odds of female infertility were found to be significantly higher with rising serum uric acid levels (Q4 [≥ 5.2 mg/dL] vs. Q1 [≤ 3.6 mg/dL]), adjusted odds ratio [aOR] = 1.59, p = 0.002]. The data suggests that there is a dose-response relationship between the two.

CONCLUSIONS

The results from this nationally representative sample from the United States confirmed the idea that there is a link between increased serum uric acid levels and female infertility. Future research is necessary to evaluate the relationship between serum uric acid levels and female infertility and explicate the underlying mechanisms of this relationship.

Elevated serum uric acid level is associated with adverse reproductive outcomes in women with polycystic ovary syndrome undergoing in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycles: a retrospective cohort study

BACKGROUND

Serum uric acid levels are elevated in polycystic ovary syndrome, however, the relationship between serum uric acid level and reproductive outcomes in women with polycystic ovary syndrome remains unclear.

OBJECTIVE

This study aimed to investigate the association between serum uric acid level and the reproductive outcomes in women with polycystic ovary syndrome undergoing in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycles.

STUDY DESIGN

This was a retrospective cohort study performed at a university-affiliated reproductive medicine center. A total of 1903 women with polycystic ovary syndrome undergoing their first in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycles between January 2010 and January 2021 were initially included. The trends for reproductive outcomes in polycystic ovary syndrome across quartiles of serum uric acid levels were assessed. A logistic regression analysis was performed to obtain the odds ratios for in vitro fertilization outcomes based on the quartiles of serum uric acid with or without adjusting for potential confounding variables. Using generalized additive models, serum uric acid was further treated as its original continuous property to visualize its nonlinear relationship with in vitro fertilization outcomes. The live birth rate was the main outcome.

RESULTS

After exclusions, a total of 883 women with polycystic ovary syndrome with their first fresh-embryo transfer cycles were included. In quartiles of serum uric acid levels, there was a significant decreasing trend in the live birth rate from the lowest quartile (Q1: 61.8%) to the highest (Q4: 45.9%) (P_trend=.002). The percentage of low birthweight increased from Q1 (22.3%) to Q4 (31.7%) (P_trend=.049). Compared with those in Q1, women in Q4 showed a significant lower probability of live birth and clinical pregnancy and a higher risk for low birthweight (all P<.05). Both the unadjusted and adjusted generalized additive models indicated that as the serum uric acid level increased, the probability of clinical pregnancy and the live birth rate exhibited an overall decreasing profile, and the risk for low birthweight showed an increasing profile.

CONCLUSION

An elevated serum uric acid level is associated with decreased probabilities of live birth and clinical pregnancy and an increased risk for low birthweight in women with polycystic ovary syndrome. However, these associations may be confounded by other factors and more well-designed studies are needed to confirm these findings in the future.

The Associations Between Alanine Aminotransferase and Other Biochemical Parameters in Lean PCOS

To explore the associations of alanine aminotransferase in lean women of polycystic ovary syndrome (PCOS) with other biochemical parameters and the potential risk factors. This is a retrospective cohort study with lean PCOS (n = 91) and healthy controls (n = 45); we reviewed the electrical records and databases of the PCOS patients in our infertility clinic between January 2019 and September 2021; independent t-test, linear correlation analysis, and multiple linear regression were used to explore the associations. Higher levels of luteinizing hormone, total testosterone, thyroid stimulating hormone, platelet count, lymphocyte count, homocysteine, alanine aminotransferase (ALT), and uric acid were identified in lean PCOS patients, while follicle-stimulating hormone level was lower in in lean PCOS as expected (P < 0.05). Of note, the linear correlation showed that BMI, total testosterone, white blood cell count, lymphocyte count, aspartate aminotransferase, and uric acid were positively associated with alanine aminotransferase (r = 0.232, 0.318, 0.218, 0.388, 0.602, 0.353 respectively, P < 0.05). After multiple linear regression was performed, total testosterone and aspartate aminotransferase were independently and positively correlated with alanine aminotransferase in lean PCOS (B = 0.251, 0.605 respectively, P < 0.05). Higher level of ALT was identified in the lean PCOS. BMI, white blood cell count, lymphocyte count, aspartate aminotransferase, uric acid, and total testosterone were positively correlated with ALT in lean PCOS. Total testosterone and aspartate aminotransferase were independently and positively associated with ALT in lean PCOS after multiple linear regression. There might exist a potential risk of afflicting liver impairment for the lean PCOS women in the earlier period. Early examination and intervention might be necessary to prevent or delay the progression of the liver disease as soon as the diagnosis of PCOS.

Emerging hallmarks of endometriosis metabolism: A promising target for the treatment of endometriosis

Endometriosis, characterized by ectopic endometrium growth in the extrauterine environment, is one of the most notable diseases of the female reproductive system. Worldwide, endometriosis affects nearly 10 % of women in their reproductive years and causes a significant decline in quality of life. Despite extensive investigations of endometriosis over the past years, the mechanisms of endometriosis pathogenesis remain unclear. In recent years, metabolic factors have increasingly been considered factors in endometriosis. There is compelling evidence regarding the progress of endometriosis in the context of severe metabolic dysfunction. Hence, the curative strategies and ongoing attempts to conquer endometriosis might start with metabolic pathways. This review focuses on metabolic mechanisms and summarizes current research progress. These findings provide valuable information for the non-intrusive diagnosis of the disease and may contribute to the understanding of the pathogenesis of endometriosis.

ATR-IR Spectroscopy Application to Diagnostic Screening of Advanced Endometriosis

Endometriosis is one of the most common gynecological diseases among young women of reproductive age. Thus far, it has not been possible to define a parameter that is sensitive and specific enough to be a recognized biomarker for diagnosing this disease. Nonspecific symptoms of endometriosis and delayed diagnosis are impulses for researching noninvasive methods of differentiating endometriosis from other gynecological disorders. We compared three groups of individuals in our research: women with endometriosis (E), patients suffering from other gynecological disorders (nonendometriosis, NE), and healthy women from the control group (C). Partial least squares discriminant analysis (PLS-DA) models were developed based on selected serum biochemical parameters, specific regions of the serum’s infrared attenuated total reflectance (FTIR ATR) spectra, and combined data. Incorporating the spectral data into the models significantly improved differentiation among the three groups, with an overall accuracy of 87.5%, 97.3%, and 98.5%, respectively. This study shows that infrared spectroscopy and discriminant analysis can be used to differentiate serum samples among women with advanced endometriosis, women without this disease, i.e., healthy women, and, most importantly, also women with other benign gynecological disorders.

The diagnostic potential of oxidative stress biomarkers for preeclampsia: systematic review and meta-analysis

Background

Preeclampsia is a multifactorial cardiovascular disorder of pregnancy. If left untreated, it can lead to severe maternal and fetal outcomes. Hence, timely diagnosis and management of preeclampsia are extremely important. Biomarkers of oxidative stress are associated with the pathogenesis of preeclampsia and therefore could be indicative of evolving preeclampsia and utilized for timely diagnosis. In this study, we conducted a systematic review and meta-analysis to determine the most reliable oxidative stress biomarkers in preeclampsia, based on their diagnostic sensitivities and specificities as well as their positive and negative predictive values.

Methods

A systematic search using PubMed, ScienceDirect, ResearchGate, and PLOS databases (1900 to March 2021) identified nine relevant studies including a total of 343 women with preeclampsia and 354 normotensive controls.

Results

Ischemia-modified albumin (IMA), uric acid (UA), and malondialdehyde (MDA) were associated with 3.38 (95% CI 2.23, 4.53), 3.05 (95% CI 2.39, 3.71), and 2.37 (95% CI 1.03, 3.70) odds ratios for preeclampsia diagnosis, respectively. The IMA showed the most promising diagnostic potential with the positive predictive ratio (PPV) of 0.852 (95% CI 0.728, 0.929) and negative predictive ratio (NPV) of 0.811 (95% CI 0.683, 0.890) for preeclampsia. Minor between-study heterogeneity was reported for these biomarkers (Higgins’ I² = 0–15.879%).

Conclusions

This systematic review and meta-analysis identified IMA, UA, and MDA as the most promising oxidative stress biomarkers associated with established preeclampsia. IMA as a biomarker of tissue damage exhibited the best diagnostic test accuracy. Thus, these oxidative stress biomarkers should be further explored in larger cohorts for preeclampsia diagnosis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13293-022-00436-0.

Biomarkers of oxidative stress are related to the pathogenesis of preeclampsia and might be indicative of evolving preeclampsia and utilized for timely diagnosis and management of preeclampsia.

Systematic review and meta-analysis were conducted to evaluate the diagnostic accuracy of oxidative stress markers based on their diagnostic sensitivities and specificities.

Clinically relevant positive predictive values (PPVs) and negative predictive values (NPVs) were determined for each biomarker.

IMA, UA, and MDA were associated with 3.38, 3.05, and 2.37 odds ratios for preeclampsia onset.

IMA exhibited the most promising diagnostic potential with an average PPV of 0.852 and NPV of 0.811, respectively. Minor heterogeneity was reported for these biomarkers (Higgins’ I² = 0–15.879%).

These oxidative stress markers should be further explored in larger cohorts for preeclampsia diagnosis.

Uric Acid and Oxidative Stress-Relationship with Cardiovascular, Metabolic, and Renal Impairment

Background: The connection between uric acid (UA) and renal impairment is well known due to the urate capacity to precipitate within the tubules or extra-renal system. Emerging studies allege a new hypothesis concerning UA and renal impairment involving a pro-inflammatory status, endothelial dysfunction, and excessive activation of renin–angiotensin–aldosterone system (RAAS). Additionally, hyperuricemia associated with oxidative stress is incriminated in DNA damage, oxidations, inflammatory cytokine production, and even cell apoptosis. There is also increasing evidence regarding the association of hyperuricemia with chronic kidney disease (CKD), cardiovascular disease, and metabolic syndrome or diabetes mellitus. Conclusions: Important aspects need to be clarified regarding hyperuricemia predisposition to oxidative stress and its effects in order to initiate the proper treatment to determine the optimal maintenance of UA level, improving patients’ long-term prognosis and their quality of life.

Plasma Diaphanous Related Formin 1 Levels Are Associated with Altered Glucose Metabolism and Insulin Resistance in Patients with Polycystic Ovary Syndrome: A Case Control Study

Background

Diaphanous related formin 1 (DIAPH1) is a novel component of advanced glycation end product (AGE) signal transduction that was recently found to participate in diabetes-related disorders, obesity, and androgen hormones. We investigated whether plasma DIAPH1 levels were a potential prognostic predictor for polycystic ovary syndrome (PCOS).

Methods

The levels of circulating plasma DIAPH1 and indicators of glucose, insulin, lipid metabolism, liver enzymes, kidney function, sex hormones, and inflammation were measured in 75 patients with PCOS and 77 healthy participants. All of the participants were divided into normal-weight (NW) and overweight/obese (OW) subgroups. Statistical analyses were performed with R studio.

Results

PCOS patients manifested hyperandrogenism, increased luteinizing hormone/follicle-stimulating hormone (LH/FSH), and accumulated body fat and insulin resistance. Plasma DIAPH1 levels were significantly decreased in women with PCOS compared to control participants, and DIAPH1 levels were distinctly reduced in OW PCOS compared to OW control subjects (P < 0.001). DIAPH1 levels correlated with fasting blood glucose (FBG), total cholesterol (TC), the homeostasis model assessment of β-cell function (HOMA-β), and LH/FSH in all participants (FBG: r = 0.351, P < 0.0001; TC: r = 0.178, P = 0.029; HOMA-β: r = −0.211, P = 0.009; LH/FSH: r = −0.172, P = 0.040). Multivariate logistic regression analysis revealed that plasma DIAPH1 levels were an independent risk factor for PCOS. A model containing DIAPH1, BMI, FBG, and testosterone was constructed to predict the risk of PCOS, with a sensitivity of 92.0% and a specificity of 80.9%. A nomogram was constructed to facilitate clinical diagnosis.

Conclusions

These findings suggest the association of plasma DIAPH1 with glucose metabolism, insulin resistance, and sex hormones and support DIAPH1 as a potential predictive factor for PCOS.

Analysis of HIF2α polymorphisms in infertile women with polycystic ovary syndrome or unexplained infertility

OBJECTIVE

To evaluate HIF2α polymorphisms and glucose metabolism in a group of women with polycystic ovary syndrome (PCOS) or unexplained infertility (UI).

PATIENTS

The infertile group (n=148) consisted of 96 women with PCOS, 52 women with UI, and176 women without infertility as a healthy control group.

INTERVENTION

We genotyped 29 single nucleotide polymorphisms (SNPs) of HIF2α by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based genotyping technology. The genetic associations were analyzed statistically.

MAIN OUTCOME MEASURES

Allele frequency, genotype distribution and haplotype analyze of the HIF2α polymorphisms were performed. Body mass index (BMI), waist circumference, uric acid (UA), high-sensitivity C-reactive protein (hsCRP), lipids, glucose and insulin tolerance - were also measured.

RESULTS

Infertile women with PCOS had a higherBMI and waist circumference, elevated hsCRP and uric acid (UA) levels, impaired glucose tolerance, and increased levels of plasma insulin compared to UI patients and healthy women. SNP analysis of HIF2α revealed that the allele and genotype frequencies of rs4953361 were significantly associated with infertile women with PCOS. Haplotype analysis of the HIF2α polymorphism identified haplotypes TGG and TGA as being associated with infertile women with PCOS. Women with the AA genotype of rs4953361 had a significantly higher BMI and post load plasma glucose and insulin levels than those of women with the GG genotype.

CONCLUSION

Infertile women with PCOS more commonly have metabolic disturbances than those with UI. This is the first study to report an association between HIF2α polymorphisms (rs4953361) and the risk of infertile women with PCOS, not UI, in Han Chinese population. These results require replication in larger populations.In this observational study, we did not report the results of a health care intervention on human participants. The study was approved by the Human Research Ethics Committee of the First Affiliated Hospital of Chongqing Medical University. Clinical data and peripheral blood samples were collected only after explaining the objectives of the study and obtaining a signed informed consent form.

Characterizing and Evaluating Diurnal Salivary Uric Acid Across Pregnancy Among Healthy Women

Uric acid levels during pregnancy have been examined as a potential indicator of risk for gestational diabetes mellites, hypertension, and related adverse birth outcomes. However, evidence supporting the utility of serum uric acid levels in predicting poor maternal and fetal health has been mixed. The lack of consistent findings may be due to limitations inherent in serum-based biomeasure evaluations, such as minimal repeated assessments and variability in the timing of these assessments. To address these gaps, we examined repeated measurements of diurnal salivary uric acid (sUA) levels in a sample of 44 healthy women across early-mid and late pregnancy. We assessed potential covariates and confounds of sUA levels and diurnal trajectories, as well as associations between maternal weight gain and blood pressure during pregnancy and sUA concentrations. Using multilevel linear models, we found sUA increased across pregnancy and displayed a robust diurnal pattern with the highest concentrations at waking, a steep decline in the early morning, and decreasing levels across the day. Maternal pre-pregnancy BMI, age, prior-night sleep duration, and fetal sex were associated with sUA levels and/or diurnal slopes. Maternal blood pressure and gestational weight gain also showed significant associations with sUA levels across pregnancy. Our results expand upon those found with serum UA measurements. Further, they demonstrate the feasibility of using at-home, minimally-invasive saliva sampling procedures to track UA levels across pregnancy with potential applications for the long-term monitoring of maternal cardiometabolic risk.

Neck Circumference Is Associated With Hyperuricemia in Women With Polycystic Ovary Syndrome

OBJECTIVE

To evaluate the association between neck circumference (NC) and hyperuricemia in women with polycystic ovary syndrome (PCOS).

METHODS

This is a cross-sectional study that recruited 601 women with PCOS from January 2018 to January 2021. PCOS was diagnosed according to the Rotterdam definition. Hyperuricemia was defined as serum uric acid level of at least 357 μmol/L.

RESULTS

PCOS females with hyperuricemia had significantly greater values of NC, body mass index (BMI), waist circumference (WC) and hip circumference (HC). NC was positively associated with serum uric acid levels, with a standardized regression coefficient of 0.34 after adjusting for confounding factors. Furthermore, logistic regression analysis showed that NC was significantly associated with an increased risk of hyperuricemia, with an adjusted odds ratio of 1.36. The associations between NC and serum uric acid levels were more considerable in those with medium/high BMI (BMI ≥ 21.63 kg/m²), all ranges of WC or medium/high HC (HC ≥ 90 cm). The optimal cut-off point of NC in predicting hyperuricemia was 32.0 cm (Youden index = 0.48), with the sensitivity and negative predictive value of 84.81% and 92.08%, respectively.

CONCLUSIONS

NC was positively correlated with serum uric acid levels and the prevalence of hyperuricemia in women with PCOS. Therefore, we suggest NC as a simple, novel, and reliable anthropometric measure to be used in the routine clinical assessment of women with PCOS to screen those at high risk of hyperuricemia.