Association between serum uric acid levels and coronary artery disease in different age and gender: a cross-sectional study

Progress of uric acid in cardiovascular disease

Due to the global prevalence of hyperuricemia (HUA), there is growing interest in research on uric acid (UA). HUA is a common condition that has various adverse consequences, including gout and kidney disease. However, recent studies have also implicated UA in the development of cardiovascular diseases (CVD) such as atrial fibrillation (AF) and coronary heart disease (CHD). Experimental and clinical research has extensively demonstrated the detrimental effects of elevated serum UA levels on cardiovascular health. Furthermore, serum UA levels have been identified as predictors of CVD outcomes following percutaneous coronary intervention (PCI) and catheter ablation. Additionally, the use of UA-lowering therapy holds important implications for the management of CVD. This review aims to consolidate the current evidence on the relationship between serum UA and CVD.

Sex differences in the association of the uric acid to high-density lipoprotein cholesterol ratio with coronary artery disease risk among Chinese nondialysis patients with CKD stages 3-5

BACKGROUND AND AIMS

Evidence has indicated that serum uric acid (UA) and high-density lipoprotein cholesterol (HDL-C) are positively and negatively associated with coronary artery disease (CAD). The UA to HDL-C ratio (UHR) has recently drawn attention as a new predictor for metabolic syndrome, inflammation and atherosclerosis. However, the association between the UHR and CAD in nondialysis chronic kidney disease (CKD) patients is still unclear.

METHODS AND RESULTS

We retrospectively analysed 733 nondialysis patients with CKD stage 3-5 who received their first coronary artery angiography (CAG), including 510 participants with CAD. All laboratory indicators were collected within one week before CAG. The median UHR of CAD and non-CAD patients was 15.52% and 12.29%, respectively. In multivariate analysis, female patients with a high UHR were 4.7 times more at risk of CAD than those with a lower UHR. Meanwhile, the positive association of the UHR with the severity of coronary artery stenosis (CAS) persisted significantly in female CAD subjects but not in males. In addition, receiver operating characteristic (ROC) curves were constructed for CAD and severe CAS. The area under the curve (AUC) for the UHR was higher than that for UA and HDL-C alone in female patients [UHR (AUC): 0.715 for CAD and 0.716 for severe CAS].

CONCLUSIONS

An elevated UHR was independently related to an increased CAD risk and the severity of CAS in nondialysis female patients with CKD stage 3-5, and was more predictive of the onset of CAD and the severity of CAS than UA or HDL-C alone.

Uric acid to high-density lipoprotein cholesterol ratio predicts adverse cardiovascular events in patients with coronary chronic total occlusion

BACKGROUND AND AIMS

Uric acid to high-density lipoprotein cholesterol ratio (UHR) is a novel index of metabolism and inflammation proposed by recent studies. The prognostic value of UHR is undetermined in patients with coronary chronic total occlusion (CTO). The aim of this study was to investigate the association of UHR with adverse cardiovascular events in patients with CTO.

METHODS AND RESULTS

In this retrospective cohort study, we enrolled 566 patients with CTO lesion in our hospital from January 2016 to December 2019. Patients were divided into three groups based on UHR level. The primary endpoint was major adverse cardiovascular event (MACE), defined as a combination of death, non-fatal MI, target vessel revascularization (TVR), and non-fatal stroke. The median follow-up time of this study was 43 months. During the follow-up, 107 (18.9%) MACEs were recorded. Kaplan-Meier survival plots show the cumulative incidence of MACE-free decreased across tertile of UHR (log-rank test, p < 0.001). In the fully adjusted model, the Hazard ratio (95% CI) of MACE was 2.16 (1.17-3.99) in tertile 3 and 2.01 (1.62-2.49) for per SD increase in UHR.

CONCLUSION

Elevated UHR predicts an increasing risk of MACE in patients with CTO. UHR is a simple and reliable indicator for risk stratification and early intervention in CTO patients.

The protective effects of uric acid against myocardial ischemia via the Nrf2 pathway

Uric acid (UA) possesses both pro- and anti-oxidative properties in ischemic heart disease, but the underlying mechanism remains unclear. We aimed to investigate UA's protective effect on myocardial ischemia by examining its effects on ECG Ischemic Alterations (EIA) and H2O2-induced oxidative stress in H9C2 myocardial cells. The incidence of EIA decreased over time and was more prevalent among women than men. A U-shaped relationship was observed between UA levels and EIA incidence, with the third quartile exhibiting a protective association. Addition of 237.9 μmol/L UA improved cellular damage and oxidative stress in H2O2-treated H9C2 cells, as determined by cell viability, LDH release, ROS levels, and total antioxidant capacity assays. UA activated the Nrf2 pathway, evidenced by increased expression of Nrf2, GCLC, and HO-1 proteins. By reversing cell cycle blockage, promoting wound healing ability, improving colony-forming capacity, and increasing angiogenesis in H2O2-treated cells, UA exhibited positive effects on cardiomyocyte growth characteristics. Additionally, use of Nrf2 inhibitor ML385 confirmed the involvement of the Nrf2 pathway by negating UA's effects on oxidatively damaged cardiomyocytes. Our findings suggest that UA induces downstream antioxidant factors to ameliorate oxidative stress by activating the Nrf2 pathway, which could be one of the targets responsible for UA's beneficial effects in myocardial ischemia.

Porous carbon nanosheets derived from two-dimensional Fe-MOF for simultaneous voltammetric sensing of dopamine and uric acid

It is of great significance for electrochemical sensors to simultaneously detect dopamine (DA) and uric acid (UA) related to biological metabolism. In this work, two-dimensional (2D) porous carbon nanosheets (CNS) was prepared as electrocatalysts to improve the sensitivity, the selectivity, and the detection limit of the simultaneous detection. First, 2D amorphous iron-metal organic frameworks (Fe-MOF) was synthesized with Fe3+and terephthalic acid via a facile wet chemistry method at room temperature. And then, CNS was prepared by pyrolysis and pickling of Fe-MOF. CNS had large specific surface area, good electrical conductivity and lots of carbon defects. The response currents of the CNS modified electrode was larger than those of the control electrodes in the simultaneous determination. The simultaneous determination was measured via differential pulse voltammetry to reduce the effect of capacitive currents on quantitative analysis. The CNS modified electrodes showed high sensitivity and low detection limit for the simultaneous detection of DA and UA. The modified electrodes have been successfully used to detect DA and UA in normal human serum.

Serum uric acid to high-density lipoprotein cholesterol ratio is a promising marker for identifying metabolic syndrome in nondiabetic Chinese men

OBJECTIVES

To explore the relationship between serum uric acid (UA) and high-density lipoprotein cholesterol (HDL-C) ratio (UHR) and metabolic syndrome (MetS) in nondiabetic individuals.

METHODS

A total of 15,760 nondiabetic participants were screened from the China National Diabetes and Metabolic Disorders Study. Pearson correlation was used to determine the correlation between the components of MetS and UHR, HDL-C, and UA. Receiver operating characteristic curves were used to evaluate the ability of UHR, HDL-C, and UA to identify MetS in the nondiabetic population.

RESULTS

A total of 6,386 men and 9,374 women were enrolled in this study. There were 1,480 (23.2%) men and 1,828 (19.5%) women with MetS. UHR significantly correlated with the components of MetS in men and women, especially with waist circumference  and triglyceride. In men, although HDL-C showed a higher specificity index, UHR presented higher sensitivity index and area under the curve (AUC) than HDL-C (P = 0.0001) and UA (P < 0.0001), with AUC (95% CI) of 0.762 (0.752-0.773). Higher AUCs of UHR relative to HDL-C and UA were also observed in the age groups <40 and 40-59 years. There was no significant difference in AUC between UHR and HDL-C in the age group ≥60 years (P = 0.370). However, similar results were not observed in women.

CONCLUSION

UHR significantly correlated with the components of MetS and could serve as a novel and reliable marker for identifying the population at a high risk of MetS in nondiabetic men, especially in younger adults.

Association between periodontitis and uric acid levels in blood and oral fluids: a systematic review and meta-analysis

BACKGROUND

Uric acid, a formerly-known antioxidant that has recently been linked to numerous inflammatory diseases as a pro-inflammatory and -oxidative mediator in pathological conditions. It is imperative to reassess the association between periodontitis and uric acid locally and systematically. The aim of this systematic review was to systemically evaluate the association between periodontitis and the uric acid (UA) levels in blood, saliva and gingival crevicular fluid (GCF).

METHODS

Relevant clinical studies up to January 28, 2023 were identified and retrieved from electronic databases including PubMed, Scopus, EMBASE and Web of Science, with periodontitis, uric acid, hyperuricemia and gout as the keywords. The weighted (WMD) or standardized mean difference (SMD) was calculated using fixed- or random-effect models. Methodological heterogeneity was assessed.

RESULTS

Sixteen eligible observational studies and one RCT were enrolled, which included 1354 patients with periodontitis and 989 controls. Three sample types for UA detection were involved, including blood (n = 8), saliva (n = 9) and GCF (n = 1). Meta-analysis demonstrated an enhanced plasma UA concentration (WMD = 1.00 mg/dL, 95% CI 0.63 to 1.37, P < 0.001) but a decreased salivary UA level (SMD = -0.95, 95% CI -1.23 to -0.68, P < 0.001) in periodontitis versus control. Statistical heterogeneity among the plasma- and saliva-tested studies were moderate (I² = 58.3%, P = 0.066) and low (I² = 33.8%, P = 0.196), respectively.

CONCLUSIONS

Within the limitations of the enrolled studies, it seems that there is an association between periodontitis and increased blood UA and decreased salivary UA. (Registration no. CRD42020172535 in Prospero).

Elevated serum uric acid is associated with cognitive improvement in older American adults: A large, population-based-analysis of the NHANES database

Background

The many studies revealing a connection between serum uric acid (SUA) and dementia have reported conflicting results. This study sought to investigate the relations between SUA and cognitive function in older adults.

Materials and methods

The sample was 2,767 American adults aged ≥60 years from the National Health and Nutrition Examination Survey 2011-2014. Cognitive performance was evaluated by the Consortium to Establish a Registry for Alzheimer's Disease test, animal fluency test, digit symbol substitution test, and composite z-score. Multivariate linear regression analyses were conducted to estimate the association between SUA and cognitive function.

Results

SUA level and cognitive function were significantly, positively correlated. Age significantly correlated with the association between SUA and cognitive function.

Conclusion

These findings support a connection between SUA and cognition, showing a positive link between SUA and cognitive scores among older American adults. We contend that a slight rise in uric acid within the normal range is advantageous for enhanced cognition. To confirm the precise dose-time-response relation, more tests will be needed.

Hyperuricemia is Related to the Risk of Cardiovascular Diseases in Ethnic Chinese Elderly Women

Background

The association between hyperuricemia (HUA) and cardiovascular diseases (CVDs) is not fully elucidated.

Objective

To assess the relationship according to factors of sex and age in the Chinese ethnic groups.

Methods

We performed a population-based cross-sectional study in a multi-ethnic population from southwestern China. HUA patients were identified by serum uric acid ≥7 mg/dL in men and 6 mg/dL in women. The outcome was composite prevalent CVDs, including coronary heart disease (CHD), stroke, and arrhythmia. Multivariate logistic regression analysis, estimating odds ratio (ORs) and 95% confidence intervals (CIs), were applied to evaluate the HUA-CVDs relationship.

Results

We included 16,618 people (37.48% Dong, 30.00% Miao, and 32.52% Bouyei) aged 30-79 years without a reduced estimated glomerular filtration rate <60 mL/min/1.73 m2. CVDs developed in 250 Dong, 196 Miao, and 205 Bouyei adults. Among women, HUA was positively associated with the risk of stroke in Dong ethnicity and CVDs in Bouyei ethnicity (ORs (95% CIs) 2.02 (1.07-3.81) and 1.66 (1.06-2.59)) compared with non-HUA. In the age-specific analysis, HUA was related to the risk of CVDs (OR 2.32, 95% CI 1.00-5.38) and CHD (5.37, 1.61-17.89) among Miao people aged < median age, CVDs (1.52, 1.11-2.08) and stroke (1.67, 1.02-2.72) among Dong adults aged ≥ median age, and CVDs (1.67, 1.16-2.40) and CHD (1.77, 1.13-2.77) among Bouyei ethnicity aged ≥ median age. After stratification by sex and the median age, for women aged > 50 years, a 55% (1.55, 1.00-2.39) and 65% (1.65, 1.02-2.66) increased risk for CVDs was observed in Dong and Bouyei ethnicities.

Conclusions

HUA may be related to an increased risk of CVDs among women in the Dong and Bouyei ethnic groups in China, especially women aged > 50 years.

Prevalence and Risk Factors of QTc Prolongation During Pregnancy

Background

Prolonged QT intervals have been observed in pregnant women, which predispose them to a higher risk of potentially lethal ventricular arrhythmias. This study was designed to evaluate the prevalence of QTc prolongation in Chinese hospitalized parturient women with single and twin pregnancies, and to explore potential risk factors associated with QTc prolongation.

Methods

This retrospective study included 1,218 patients from a large Chinese population between January 2014 and October 2020. Data from parturient women with single and twin pregnancies without pre-pregnancy cardiac diseases were collected. QTc was corrected by the Fridericia formula [QTc = QT/RR(1/3)], and QTc ≥ 460 ms for females was defined as prolonged QTc, QTc ≥ 500 ms was defined as severely prolonged QTc. The prevalence and common risk factors of QTc prolongation during pregnancy were analyzed in this cohort. Uni- and multivariable logistic regression analysis were performed to identify clinical parameters associated with QTc prolongation in this population.

Results

The prevalence of QTc prolongation was 48.19% among this population, 10.56% in single pregnancy, 89.44% in twin pregnancies. The prevalence of severely prolonged QTc was 23.48% among the total cohort, 0.49% in single pregnancy, and 46.47% in twin pregnancies. The mean QTc interval was significantly longer in twin pregnancies than in single pregnancy (498.65 ± 38.24 vs. 424.96 ± 27.67 ms, P < 0.001). Systolic blood pressure, diastolic blood pressure, total cholesterol, serum uric acid, gestational hypertension and twin pregnancies were associated with QTc prolongation in parturient women.

Conclusion

This is the first study to assess the prevalence and risk factors of QTc prolongation between single and twin pregnancies. QTc prolongation is more prevalent, and QTc intervals are significantly longer in twin pregnancies as compared to single pregnancy.

A multiethnic association analysis of hyperuricaemia with cardiovascular risk in rural and urban areas in Chinese adults

Comprehensive research on rural-urban disparities in the association of hyperuricaemia (HUA) with cardiovascular disease (CVD) in China, especially among minority groups, is limited. We explored the HUA-CVD relationship between rural and urban areas within ethnic Chinese groups. We included Dong, Miao, and Bouyei adults in Southwest China from the China Multi-Ethnic Cohort Study. Multivariable logistic regression models were used to assess the relationship between HUA and CVD in both residences. We performed stratified analyses by sex and age. The study population included 16,618 people (37.48% Dong, 30.00% Miao, and 32.52% Bouyei) without a reduced estimated glomerular filtration rate. We identified 476 (188 Dong, 119 Miao, and 169 Bouyei) and 175 (62 Dong, 77 Miao, and 36 Bouyei) CVD cases in rural and urban areas. Compared to urban residents, an at least 49% increased CVD risk (adjusted OR 1.49, 95%CI 1.06-2.08 for the Dong ethnic group; 1.55, 1.07-2.25 for the Bouyei ethnic group) and a 1.65-fold elevated coronary heart disease risk (1.65, 1.03-2.64) related to HUA was present in rural residents. Moreover, HUA was positively associated with increased risk of CVD and coronary heart disease in rural women (2.05, 1.26-3.31; 2.11, 1.19-3.75) and rural older adults (1.83, 1.22-2.75; 2.32, 1.39-3.87) among the Bouyei ethnic group, respectively. We found rural elderly individuals with HUA among the Dong ethnic group had a 52% elevated risk of CVD (1.52, 1.05-2.21); furthermore, an at least 79% increased risk of stroke related to HUA was observed in women (2.24, 1.09-4.62) and elderly people (1.79, 1.02-3.13) in rural areas among the Dong ethnic group. But a positive association was not found among the Miao ethnic group. Screening early-onset HUA patients may be helpful for the control and prevention of CVD in rural residents, especially for women and older adults living in a rural community, among the Dong and Bouyei ethnic groups in China.

Carotid Artery Pathology in Inflammatory Diseases

There is considerable evidence that patients with inflammatory conditions are at higher risk of developing cardiovascular (CV) disease including carotid artery stenosis. CV disease accounts for 35-50% of the excess mortality in patients with inflammatory diseases such as rheumatoid arthritis, with cerebrovascular disease being the second leading cause of death. We review current evidence regarding the association of inflammatory conditions and specifically carotid artery disease. Clinical epidemiological observations suggest that mechanisms other than classic risk factors may promote accelerated atherogenesis in rheumatoid and other inflammatory arthritis and carotid artery disease is increased in individuals with these conditions. Additional studies to better understand the underlying mechanisms and targeted strategies to mitigate such risk are indicated. For now, lifestyle modifications, aggressive treatment of risk factors and lipid lowering therapy in appropriate individuals is indicated.

The serum levels of testosterone in coronary artery disease patients; relation to NO, eNOS, endothelin-1, and disease severity

OBJECTIVES

The changes in testosterone level and its correlation with the endothelial nitric oxide systems balance in patients with coronary artery disease (CAD) remains uncertain. Therefore, in our study, we aimed to evaluate the levels of testosterone, endothelin-1 (ET-1), nitric oxide (NO), and endothelial NOS (eNOS) in CAD patients, and control group to find the relationship between these parameters and disease severity.

METHODS

Forty-four patients as CAD group with significant (≥50%) stenosis confirmed by angiography was included in the study, and 40 healthy men were included as the control group. According to the number of vessels obstruction, CAD severity was determined. The serum indicated parameters were assessed to discriminate between patients and controls.

RESULTS

It was found that testosterone levels in the CDA group were significantly lower than those of the control group (p<0.05). In addition, the level of ET-1 in the CAD group was higher than that in the control group, but levels of NO and eNOS in observation were significantly lower than those in the control group (p<0.05). The correlation analysis revealed that testosterone was passivity correlated with serum NO levels (r=0.550, p=0.001).

CONCLUSIONS

The current study reports that serum levels of testosterone are closely related to endothelial NO levels and might be of relevance to the pathogenesis of endothelial dysfunction and disease severity in CAD patients.

Impact of Serum Uric Acid Concentration on the Risk of Cardiovascular Disease: A Cohort Study Conducted in Northern China

BACKGROUND

The results of previous studies of the relationship between serum uric acid (SUA) and the risk of cardiovascular disease (CVD) have been inconsistent due to confounding factors caused by other known cardiovascular risk factors.

OBJECTIVES

This study aimed to evaluate the relationship between SUA and incident CVD in middle-aged and elderly Chinese people, who were stratified according to body mass index (BMI).

METHODS

This study recruited 5,721 participants of 40-75 years of age, who were free of CVD at baseline and who underwent follow-up from 2008 to 2017. Participants were categorized in SUA quintiles. Cox proportional hazard and Kaplan-Meier survival analysis were used to compare CVD incidence among the SUA groups. The correlations between SUA and CVD incidence in groups with differing BMI and waist circumference (WC) were also analyzed. A P value <0.05 was considered statistically significant.

RESULTS

During a mean follow-up period of 7.6 years, CVD incidence increased with SUA (log-rank test p<0. 001). Compared with the first quintile, the adjusted hazard ratios (95% confidence interval (CI)) for the development of CVD were 1.08 (0.78-1.65), 1.17 (0.88-1.77), 1.47 (1.12-2.21), and 1.68 (1.28-2.44) for the second to fifth quintiles, respectively. This relationship was clearer in participants with normal BMI and WC. The adjusted hazard ratio for each 100 μmol/L increase in SUA was 1.13 (95% CI: 1.02-1.39) for CVD events.

CONCLUSIONS

High SUA is an independent risk factor for CVD in middle-aged and elderly northern Chinese people. This effect is maintained even after stratification according to measures of leanness/obesity.

The Role of ABCG2 in the Pathogenesis of Primary Hyperuricemia and Gout-An Update

Urate homeostasis in humans is a complex and highly heritable process that involves i.e., metabolic urate biosynthesis, renal urate reabsorption, as well as renal and extrarenal urate excretion. Importantly, disturbances in urate excretion are a common cause of hyperuricemia and gout. The majority of urate is eliminated by glomerular filtration in the kidney followed by an, as yet, not fully elucidated interplay of multiple transporters involved in the reabsorption or excretion of urate in the succeeding segments of the nephron. In this context, genome-wide association studies and subsequent functional analyses have identified the ATP-binding cassette (ABC) transporter ABCG2 as an important urate transporter and have highlighted the role of single nucleotide polymorphisms (SNPs) in the pathogenesis of reduced cellular urate efflux, hyperuricemia, and early-onset gout. Recent publications also suggest that ABCG2 is particularly involved in intestinal urate elimination and thus may represent an interesting new target for pharmacotherapeutic intervention in hyperuricemia and gout. In this review, we specifically address the involvement of ABCG2 in renal and extrarenal urate elimination. In addition, we will shed light on newly identified polymorphisms in ABCG2 associated with early-onset gout.

Serum uric acid is positively associated with the prevalence of nonalcoholic fatty liver in non-obese type 2 diabetes patients in a Chinese population

AIMS

To investigate whether SUA is independently associated with NAFLD in non-obese type 2 diabetic patients in a Chinese population.

METHODS

A cross-sectional study was carried out among 400 non-obese type 2 diabetic inpatients. Patients were stratified according to SUA levels and presence/absence of NAFLD. The clinical and laboratory features were collected retrospectively. Multivariate logistic regression analysis was conducted to estimate odds ratios of SUA for NAFLD.

RESULTS

The levels of SUA were significantly higher in patients with NAFLD than those without NAFLD. SUA was positively associated with the risk factors of NAFLD such as BMI, serum insulin and lipids. The odds of NAFLD were increasingly higher from the second to the fourth quartile of SUA as compared to the lowest quartile. After adjustment for age, gender, BMI and other metabolic components, the odds of NAFLD remained significantly increased for quartile 4.

CONCLUSIONS

SUA levels are strongly and independently associated with the prevalence of NAFLD. SUA may be used as a useful predictor to stratify the higher risks for NAFLD of non-obese type 2 diabetes patients.

Risk Predictors of High Uric Acid Levels Among Patients with Type-2 Diabetes

OBJECTIVE

Patients with diabetes are at higher risk of the negative consequences of hyperuricemia. The objective of this study was to investigate gender and age-specific differences in the uric acid levels and to evaluate the associated risk factors among patients with diabetes.

METHODS

A retrospective cross-sectional study was conducted at Strategic Center for Diabetes Research from September 2019 to January 2020, among adult type-2 diabetic patients. Serum uric acid (SUA) and several other metabolic and clinical parameters were examined. Multiple regression analysis was done to identify risk factors independently associated with hyperuricemia.

RESULTS

A total of 433 patients were included in the analysis. SUA level was higher in males than females (5.82±1.65 mg/dL versus 5.29±1.54 mg/dL, p < 0.001). The prevalence of hyperuricemia was higher in females than males (28.8% versus 20.5%, p = 0.049). There was no significant difference in uric acid levels or the prevalence of hyperuricemia by age groups in the total sample or gender-stratified samples. In multivariate analysis, hyperuricemia was associated with bigger hip circumference (odds ratios [OR] were 1.03, 95% CI = 1.01-1.05), higher triglycerides (OR = 1.005, 95% CI = 1.002-1.008), and higher serum creatinine (OR = 1.34, 95% CI = 1.21-1.49). Hip circumference, total cholesterol, high-density lipoprotein, and serum creatinine were independent risk factors in males, while triglycerides and higher serum creatinine were independent risk factors among females.

CONCLUSION

The present study demonstrates gender-specific differences in the uric acid levels and hyperuricemia prevalence. In males and females, hyperuricemia was associated with hip circumference, total cholesterol, high-density lipoprotein, triglycerides, and serum creatinine. Future large studies are needed to confirm our findings, especially in elderly females.

Sex differences in uric acid and NT-pro BNP assessments during coronary severity

To investigate the correlation between uric acid (UA) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels and coronary artery severity in acute coronary syndrome patients of different sexes.A total of 134 patients with acute coronary syndrome (ACS) were investigated. According to sex, there were 96 cases in male group and 38 cases in female group. According to the number of diseased vessels, the degree of coronary artery lesion was determined and divided into negative group (n = 21), single vessel lesion group (n = 43), double vessel lesion group (n = 38), and 3 vessel lesion group (n = 32).Univariate analysis showed that UA, NT-proBNP was correlated with the severity of ACS (P < .05). UA was an independent risk factor for the severity of coronary artery disease in female group (P < .05), but not in male group (P > .05). There was no significant correlation between NT-proBNP and severity of coronary artery disease in different sex (P > .05).UA was significantly correlated with the severity of coronary heart disease, especially in women, but not in men. The level of NT-proBNP was positively correlated with the severity of coronary artery, but no significant difference was found in different sexes.

Serum Uric Acid is Associated with Renal Prognosis of Lupus Nephritis in Women but not in Men

Lupus nephritis (LN) is a major complication of systemic lupus erythematosus. Early intervention in lupus nephritis improves prognosis. There is an association between hyperuricemia and lupus nephritis; nevertheless, the sex-specific role of uric acid in lupus nephritis remains unclear. We retrospectively analyzed 578 patients diagnosed with LN by renal biopsy. We determine the relationship of serum uric acid to progression of LN using Kaplan–Meier survival analyses and Cox proportional hazards models. The primary end point was LN progression defined as the initiation of dialysis or kidney transplantation. Men had higher mean serum uric acid levels than did women. Every 1 mg/dL increase in baseline uric acid level increased the risk of LN progression by 15.1%. The serum uric acid level was an independent risk factor for LN progression in women (hazard ratio [HR], 1.158; confidence interval [CI], 1.018–1.317; p = 0.028) but not in men (HR, 1.499; CI, 0.964–2.331; p = 0.072). Sensitivity analysis involving serum uric acid terciles generated consistent and robust results. Serum uric acid level was an independent risk factor for LN progression in women but not in men.

Uric Acid as a Potential Peripheral Biomarker for Disease Features in Huntington's Patients

Oxidative stress has long been implicated in the pathophysiology and progression of Huntington's disease (HD). Uric acid (UA) is a naturally occurring antioxidant that is present in the brain and periphery. Growing evidence has implicated UA as a molecular biomarker for several neurodegenerative diseases, most notably Parkinson's disease (PD). In this study, we investigated UA levels in clinical samples from HD patients and normal controls (NCs) and assessed potential relationships between UA levels and disease and clinical data. UA levels were measured in plasma (n = 107) and saliva (n = 178) samples from premanifest (pre-HD) and manifest HD patients and control subjects. Gender effects of UA levels were observed in both biofluids, with male patients showing higher UA levels compared to female patients. Comparisons of UA levels across diagnostic groups, separated by gender, revealed that both plasma and salivary UA levels were significantly lower in female pre-HD and manifest HD patients compared to NCs. Salivary levels of UA were also significantly lower in male manifest HD patients versus controls, but not in plasma. Correlations of peripheral UA levels to clinical data also showed differences according to gender. In male HD patients, both plasma and salivary UA levels were significantly negatively correlated with total functional capacity (TFC), while positive correlations were observed with total motor score (TMS). Female HD patients showed a significant positive correlation between plasma UA levels and TMS, while salivary UA levels from female patients were significantly correlated to disease burden. Finally, in a separate cohort, we show that UA levels are decreased in postmortem prefrontal cortical samples (n = 20) from HD subjects compared to matched controls. These findings suggest that decreased levels of UA in the brains of HD patients can be reflected in peripheral fluids, with salivary measures of UA particularly offering significant promise as a potentially relevant, non-invasive biomarker of disease symptoms and burden. Our findings further highlight the impact of sexual dimorphism in HD pathophysiology.

The serum uric acid level in females may be a better indicator of metabolic syndrome and its components than in males in a Japanese population

BACKGROUND

Although the level of uric acid (UA) is higher in males, increased UA level in females was reported to be closely associated with prevalence of metabolic syndrome (Mets) leading to atherosclerotic cardiovascular disease (ASCVD). Few data exist regarding the gender diferences in relationship between the serum UA levels and cardo-metabolic risk in the Japanese population, which generally contains a lower proportion of obesity than Western populations.

METHODS

This cross-sectional study was designed to investigate, by gender, the association between the serum UA level and abdominal obesity, and thereby cardio-metabolic risk i.e. presence of Mets and its components using a sample of 8567 apparently healthy subjects females: n = 3334, males: n = 5233 at the Health Planning Center of Nihon University Hospital between September 2015 and August 2016.

RESULTS

Receiver operating characteristic analysis was performed to reveal the accuracy of serum UA level as a predictor of abdominal obesity based on the Japanese criteria of Mets (females vs. males: area under the curve, 0.751 vs 0.609). Furthermore, the serum UA level and proportion of abdominal obesity rose with increasing age in females; in males, however, these parameters did not change in parallel with age. Furthermore, the serum UA levels in females reflected a status of cardio-metabolic risk when compared with males in a multi-logistic regression analysis. It is particularly worth noting that in the above-mentioned multivariate logistic regression analysis, the odds ratio of hyperuricemia in females was generally 1.3-2.5 times higher than that in males.

CONCLUSIONS

Compared with males, increased serum UA level in females might be involved in abdominal obesity and cardio-metabolic risk, possibly leading to the development of ASCVD even in a Japanese population. This may be due to gender differences affecting the development of abdominal obesity and changes in the serum UA levels with age.

CLINICAL TRIAL REGISTRATION

UMIN (http://www.umin.ac.jp/) Study ID:　UMIN000035901retrospectively registered 1 March 2018.

The Effects of Hyperuricemia on the Prognosis of IgA Nephropathy are More Potent in Females

Hyperuricemia is a potential risk factor for immunoglobulin A nephropathy (IgAN) progression but its sex-specific effects on IgAN progression remain unclear. This study aimed to determine the effect of serum uric acid on IgAN progression and whether its effect varied according to sex. A total of 4339 patients who diagnosed with IgAN by renal biopsy were retrospectively analyzed. We assessed the association of serum uric acid on IgAN progression using Kaplan–Meier survival analyses and Cox proportional hazards models. The study’s primary end point was IgAN progression that was defined as a 50% decline in the estimated glomerular filtration rate or the initiation of dialysis. On average, the serum uric acid levels were higher in the men than in the women. In the fully adjusted Cox proportional hazards model that considered all subjects, the risk of IgAN progression increased by about 25.6% for every 1 mg/dL increase in the baseline uric acid level. The serum uric acid level was an independent risk factor for IgAN progression in both sexes but its effect was more pronounced in the women (hazard ratio [HR], 1.383; confidence interval [CI],1.263 to 1.514; p < 0.001) than in the men (HR, 1.181; CI, 1.097 to 1.272; p < 0.001) (p_interaction < 0.001). A sensitivity analysis involving serum uric acid quartiles generated consistent and robust results. In conclusion, the serum uric acid level was an independent risk factor for IgAN progression and its effect was more pronounced among the women compared with that among the men.

Sex-Specific Association Between Serum Uric Acid and Retinal Microvessels

BACKGROUND As epidemiological findings are still controversial, animal experiments have probed into the potential link between uric acid and damage to microvessels. The present study examined the association of serum uric acid (SUA) with the retinal vascular caliber and retinal vascular fractal dimension (Df) in males and females utilizing a cross-sectional study design. MATERIAL AND METHODS A total of 2169 subjects from 7 sampling units were enrolled. Retinal vascular parameters were analyzed with a semi-automated computer-based program. The central retinal arteriolar equivalent, central retinal venular equivalent, and Df were linearly and categorically measured in males and females and at various SUA levels. RESULTS The analysis revealed that per SD SUA increase was associated with an increase of 0.848 µm in the arteriolar caliber, and an increase of 1.618 µm in the venular caliber only in females. No significant correlation was found between Df and SUA in females or in males. Further adjusted for more cardiovascular risk factors did not change the results. CONCLUSIONS By exploring a Chinese coastal population, we elucidate the association between SUA with retinal arterioles and venules in females. Df, as a mathematical index of retinal blood vascular complexity, is not correlated with SUA or hyperuricemia.