Uric acid enhances PKC-dependent eNOS phosphorylation and mediates cellular ER stress: A mechanism for uric acid-induced endothelial dysfunction

Serum uric acid and pulmonary arterial hypertension: A two-sample Mendelian randomization study

BACKGROUND

Observational studies have suggested a correlation between hyperuricemia and pulmonary arterial hypertension (PAH), yet the causal relationship remains uncertain. We aimed to establish this link using Mendelian Randomization (MR) methods.

OBJECTIVES

Based on publicly accessible data, our study employs MR to determine the causal relationship between uric acid (UA) and PAH.

METHOD

MR analysis was conducted among individuals of European descent. Genetic instruments linked to UA (p-value < 5 × 10-8) were extracted from the Chronic Kidney Disease Genetic Consortium and genome-wide association study databases. PAH risk genetic associations were sourced separately. We employed four MR methods (MR-Egger, weighted median, inverse variance weighted, and weighted mode) with selected instrumental variables to assess the causal association between UA and PAH. MR-PRESSO was used to evaluate pleiotropy and outlier Single Nucleotide Polymorphisms (SNPs), while Cochran's Q test and funnel plot assessed SNP heterogeneity. Leave-one-out analysis examined SNP impacts on causal assessment.

RESULT

Two-sample MR analysis revealed a positive, causal relationship between UA levels and PAH.

CONCLUSION

Our MR analysis provides robust evidence of a causal link between serum UA and PAH, suggesting UA's potential as a biomarker and therapeutic target for PAH.

Hyperuricemia and its related diseases: mechanisms and advances in therapy

Hyperuricemia, characterized by elevated levels of serum uric acid (SUA), is linked to a spectrum of commodities such as gout, cardiovascular diseases, renal disorders, metabolic syndrome, and diabetes, etc. Significantly impairing the quality of life for those affected, the prevalence of hyperuricemia is an upward trend globally, especially in most developed countries. UA possesses a multifaceted role, such as antioxidant, pro-oxidative, pro-inflammatory, nitric oxide modulating, anti-aging, and immune effects, which are significant in both physiological and pathological contexts. The equilibrium of circulating urate levels hinges on the interplay between production and excretion, a delicate balance orchestrated by urate transporter functions across various epithelial tissues and cell types. While existing research has identified hyperuricemia involvement in numerous biological processes and signaling pathways, the precise mechanisms connecting elevated UA levels to disease etiology remain to be fully elucidated. In addition, the influence of genetic susceptibilities and environmental determinants on hyperuricemia calls for a detailed and nuanced examination. This review compiles data from global epidemiological studies and clinical practices, exploring the physiological processes and the genetic foundations of urate transporters in depth. Furthermore, we uncover the complex mechanisms by which the UA induced inflammation influences metabolic processes in individuals with hyperuricemia and the association with its relative disease, offering a foundation for innovative therapeutic approaches and advanced pharmacological strategies.

SGLT2 Inhibitors and How They Work Beyond the Glucosuric Effect. State of the Art

Type 2 diabetes mellitus (T2DM) is associated with a heightened risk of cardiovascular and renal complications. While glycemic control remains essential, newer therapeutic options, such as SGLT2 inhibitors, offer additional benefits beyond glucose reduction. This review delves into the mechanisms underlying the cardio-renal protective effects of SGLT2 inhibitors. By inducing relative hypoglycemia, these agents promote ketogenesis, optimize myocardial energy metabolism, and reduce lipotoxicity. Additionally, SGLT2 inhibitors exert renoprotective actions by enhancing renal perfusion, attenuating inflammation, and improving iron metabolism. These pleiotropic effects, including modulation of blood pressure, reduction of uric acid, and improved endothelial function, collectively contribute to the cardiovascular and renal benefits observed with SGLT2 inhibitor therapy. This review will provide clinicians with essential knowledge, understanding, and a clear recollection of this pharmacological group's mechanism of action.

Correlation between serum uric acid to high-density lipoprotein cholesterol ratio and atrial fibrillation in patients with NAFLD

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is independently associated with atrial fibrillation (AF) risk. The uric acid (UA) to high-density lipoprotein cholesterol (HDL-C) ratio (UHR) has been shown to be closely associated with cardiovascular disease (CVD) and NAFLD. The aim of this study is to clarify whether elevated UHR is associated with the occurrence of AF in patients with NAFLD and to determine whether UHR predicted AF.

METHODS

Patients diagnosed with NAFLD in the Department of Cardiovascular Medicine of the Second Hospital of Shanxi Medical University from January 1, 2020, to December 31, 2021, were retrospectively enrolled in this study. The study subjects were categorized into AF group and non-AF group based on the presence or absence of combined AF. Logistic regression was performed to evaluate the correlation between UHR and AF. Sensitivity analysis and subgroup interaction analysis were performed to verify the robustness of the study results. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff value for UHR to predict the development of AF in patients with NAFLD.

RESULTS

A total of 421 patients with NAFLD were included, including 171 in the AF group and 250 in the non-AF group. In the univariate regression analysis, NAFLD patients with higher UHR were more likely to experience AF, and the risk of AF persisted after confounding factors were adjusted for (OR: 1.010, 95%CI: 1.007-1.013, P<0.001). AF risk increased with increasing UHR quartile (P for trend < 0.001). Despite normal serum UA and HDL-C, UHR was still connected with AF in patients with NAFLD. All subgroup variables did not interact significantly with UHR in the subgroup analysis. The ROC curve analysis showed that the areas under the curve for UA, HDL-C, and UHR were 0.702, 0.606, and 0.720, respectively, suggesting that UHR has a higher predictive value for AF occurrence in NAFLD patients compared to HDL-C or UA alone.

CONCLUSION

Increased UHR level was independently correlated with a high risk of AF in NAFLD patients.

Emerging Roles of Xanthine Oxidoreductase in Chronic Kidney Disease

Xanthine Oxidoreductase (XOR) is a ubiquitous, essential enzyme responsible for the terminal steps of purine catabolism, ultimately producing uric acid that is eliminated by the kidneys. XOR is also a physiological source of superoxide ion, hydrogen peroxide, and nitric oxide, which can function as second messengers in the activation of various physiological pathways, as well as contribute to the development and the progression of chronic conditions including kidney diseases, which are increasing in prevalence worldwide. XOR activity can promote oxidative distress, endothelial dysfunction, and inflammation through the biological effects of reactive oxygen species; nitric oxide and uric acid are the major products of XOR activity. However, the complex relationship of these reactions in disease settings has long been debated, and the environmental influences and genetics remain largely unknown. In this review, we give an overview of the biochemistry, biology, environmental, and current clinical impact of XOR in the kidney. Finally, we highlight recent genetic studies linking XOR and risk for kidney disease, igniting enthusiasm for future biomarker development and novel therapeutic approaches targeting XOR.

The prognostic value of combined uric acid and neutrophil-to-lymphocyte ratio in acute ischemic stroke patients treated with intravenous thrombolysis

BACKGROUND

Serum uric acid (UA) and the neutrophil-to-lymphocyte ratio (NLR) have been reported to be associated with outcomes in acute ischemic stroke (AIS). However, whether UA is related to the prognosis of AIS patients undergoing intravenous thrombolysis (IVT) remains inconclusive. We sought to explore the combined effect of UA and NLR on the prognosis of AIS treated with IVT.

METHODS

A total of 555 AIS patients receiving IVT treatment were enrolled. Patients were categorized into four groups according to the levels of UA and NLR: LNNU (low NLR and normal UA), LNHU (low NLR and high UA), HNNU (high NLR and normal UA), and HNHU (high NLR and high UA). Multivariable logistic regression analysis was used to evaluate the value of serum UA level and NLR in predicting prognosis. The primary outcomes were major disability (modified Rankin scale (mRS) score 3-5) and death within 3 months.

RESULTS

After multivariate adjustment, a high NLR (≥ 3.94) increased the risk of 3-month death or major disability (OR, 2.23; 95% CI, 1.42 to 3.55, p < 0.001). However, there was no statistically significant association between a high UA level (≥ 313.00 µmol/L) and clinical outcome. HNHU was associated with a 5.09-fold increase in the risk of death (OR, 5.09; 95% CI, 1.31-19.83; P value = 0.019) and a 1.98-fold increase in the risk of major disability (OR, 1.98; 95% CI 1.07-3.68; P value = 0.030) in comparison to LNNU.

CONCLUSIONS

High serum UA levels combined with high NLR were independently associated with 3-month death and major disability in AIS patients after IVT.

The association between monocyte-to-high-density lipoprotein ratio and hyperuricemia: Results from 2009 to 2018

Previous research has suggested that the monocyte-to-high-density lipoprotein ratio (MHR), an emerging inflammatory biomarker, holds promise in predicting the prevalence of various cardiovascular and metabolic diseases. However, earlier investigations were constrained by the relatively modest sample sizes. This study endeavored to expand the sample size and conduct a more comprehensive exploration of the potential relationship between MHR and hyperuricemia. This cross-sectional study incorporated data from participants of the 2009 to 2018 National Health and Nutrition Examination Survey (NHANES) with complete and qualifying information. MHR was determined by calculating the ratio between monocyte count and high-density lipoprotein levels. Various statistical methodologies such as weighted multivariate logistic regression, subgroup analysis, smoothed curve fitting, and threshold analysis, have been used to explore the correlation between hyperuricemia and MHR. The study included a cohort of 17,694 participants, of whom 3512 were diagnosed with hyperuricemia. MHR levels were notably higher in the hyperuricemia group than in the normal group, aligning with an elevated body mass index (BMI). A comprehensive multivariate logistic analysis, accounting for all relevant adjustments, revealed a notable positive correlation between MHR and hyperuricemia (P < .001, OR = 1.98, 95% CI: 1.54-2.54). Subgroup analysis indicated that the MHR exhibited an enhanced predictive capacity for identifying hyperuricemia risk, particularly in females (P < .05). Curvilinear and threshold analyses revealed a nonlinear association between MHR and hyperuricemia prevalence, with a notable inflection point at 0.826. In the US population, a clear positive correlation was observed between the MHR and prevalence of hyperuricemia. Importantly, the MHR is a more robust predictor of hyperuricemia risk in females. Further investigations are required to confirm these findings.

Baseline Uric Acid Levels and Intravenous Thrombolysis Outcomes in Patients With Acute Ischemic Stroke: A Prospective Cohort Study

BACKGROUND

The study aimed to investigate the relationship between uric acid (UA) levels and functional outcomes at 3 months in patients with acute ischemic stroke (AIS) who underwent intravenous thrombolysis (IVT).

METHODS AND RESULTS

This prospective cohort study included 1001 consecutive patients with AIS who underwent IVT. The correlation between UA levels and post-IVT AIS outcomes was examined. Any nonlinear relationship was assessed using a restricted cubic spline function. The nonlinear P value for the association of UA levels with favorable (modified Rankin Scale [mRS] score ≤2) and excellent (mRS score ≤1) outcomes at 3 months post-IVT were <0.001 and 0.001, respectively. However, for patients with and without hyperuricemia, no evident nonlinear relationship was observed between UA levels and favorable 3-month post-IVT outcomes, with nonlinear P values of 0.299 and 0.207, respectively. The corresponding interaction analysis yielded a P value of 0.001, indicating significant heterogeneity. Similar results were obtained for excellent outcomes at 3 months post-IVT. In the hyperuricemia group, increased UA levels by 50 μmol/L reduced the odds of a favorable 3-month post-AIS outcome (odds ratio [OR], 0.75 [95% CI, 0.57-0.97]). Conversely, in the nonhyperuricemia group, a similar UA increase was linked to higher favorable outcome odds (OR, 1.31 [95% CI, 1.15-1.50]).

CONCLUSIONS

An inverted U-shaped nonlinear relationship was observed between UA levels and favorable and excellent outcomes at 3 months in patients with AIS who underwent IVT. Higher UA levels predict favorable outcomes in patients without hyperuricemia but unfavorable outcomes in those with hyperuricemia.

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.

Incorporating uric acid into the CHA2DS2-VASc score improves the prediction of new-onset atrial fibrillation in patients with acute myocardial infarction

BACKGROUND

New-onset atrial fibrillation (NOAF) is a common cardiac arrhythmia observed in patients with acute myocardial infarction (AMI) and is associated with worse outcomes. While uric acid has been proposed as a potential biomarker for predicting atrial fibrillation, its association with NOAF in patients with AMI and its incremental discriminative ability when added to the CHA2DS2-VASc score are not well established.

METHODS

We conducted a retrospective analysis of 1000 consecutive patients with AMI without a history of atrial fibrillation between January 2018 and December 2020. Continuous electrocardiographic monitoring was performed during the patients' hospital stay to detect NOAF. We assessed the predictive ability of the different scoring models using receiver operating characteristic (ROC) curves. In addition, we employed the area under the curve (AUC), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) analyses to assess the incremental discriminative ability of uric acid when added to the CHA2DS2-VASc score.

RESULTS

Ninety-three patients (9.3%) developed NOAF during hospitalisation. In multivariate regression analyses, the adjusted odds ratio (OR) for NOAF was 1.439 per one standard deviation increase in uric acid level (95% confidence intervals (CI):1.182-1.753, p < 0.001). The ROC curve analysis revealed that the AUC for uric acid was 0.667 (95% CI:0.601-0.719), while the AUC for the CHA2DS2-VASc score was 0.678 (95% CI:0.623-0.734). After integrating the uric acid variable into the CHA2DS2-VASc score, the combined score yielded an improved AUC of 0.737 (95% CI:0.709-0.764, p = 0.009). Furthermore, there was a significant improvement in both IDI and NRI, indicating an incremental improvement in discriminative ability (IDI = 0.041, p < 0.001; NRI = 0.627, p < 0.001).

CONCLUSION

Our study suggests that uric acid level is an independent risk factor for the development of NOAF after AMI. Furthermore, the incorporation of uric acid into the CHA2DS2-VASc score significantly improves the discriminative ability of the score in identifying patients at high risk for NOAF.

Uric acid metabolism promotes apoptosis against Bombyx mori nucleopolyhedrovirus in silkworm, Bombyx mori

The white epidermis of silkworms is due to the accumulation of uric acid crystals. Abnormal silkworm uric acid metabolism decreases uric acid production, leading to a transparent or translucent phenotype. The oily silkworm op50 is a mutant strain with a highly transparent epidermis derived from the p50 strain. It shows more susceptibility to Bombyx mori nucleopolyhedrovirus (BmNPV) infection than the wild type; however, the underlying mechanism is unknown. This study analysed the changes in 34 metabolites in p50 and op50 at different times following BmNPV infection based on comparative metabolomics. The differential metabolites were mainly clustered in six metabolic pathways. Of these, the uric acid pathway was identified as critical for resistance in silkworms, as feeding with inosine significantly enhanced larval resistance compared to other metabolites and modulated other metabolic pathways. Additionally, the increased level of resistance to BmNPV in inosine-fed silkworms was associated with the regulation of apoptosis, which is mediated by the reactive oxygen species produced during uric acid synthesis. Furthermore, feeding the industrial strain Jingsong (JS) with inosine significantly increased the level of larval resistance to BmNPV, indicating its potential application in controlling the virus in sericulture. These results lay the foundation for clarifying the resistance mechanism of silkworms to BmNPV and provide new strategies and methods for the biological control of pests.

Associations of serum uric acid with cardiovascular disease risk factors: a retrospective cohort study in southeastern China

OBJECTIVE

To evaluate the associations between serum uric acid (SUA) levels and cardiovascular disease (CVD) risk factors, focusing on potential sex-specific differences.

DESIGN

A retrospective cohort study.

SETTING

A large community-based survey was conducted every two years from 2010 to 2018 in Hangzhou, Zhejiang Province, outheastern China.

PARTICIPANTS

6119 participants aged 40 years and above who underwent at least three times of physical examinations were enrolled.

METHODS

Participants were categorised into four groups (Q1-Q4) based on baseline SUA quartiles within the normal range, with hyperuricaemia (HUA) as the fifth group. The Q1 was the reference. By stratifying participants by gender, the relationships between SUA levels and systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG) and total cholesterol (TC) were investigated using linear regression models in the generalised estimating equation. Additionally, the associations of elevated SUA levels and HUA with hypertension, hyperglycaemia and dyslipidaemia were correspondingly examined using multivariate logistic regression models.

RESULTS

After adjusting for confounding variables, we found positive associations between SUA levels and SBP, DBP, FBG and TC in women, and with TC in men (p<0.01). Likewise, elevated SUA quartiles and HUA were linked to increased dyslipidaemia risk in both sexes, and increased hyperglycaemia risk only in women, with HRs (95% CI) of 1.64 (1.05 to 2.55) and 2.37 (1.47 to 3.81) in the Q4 and HUA group, respectively. Women with HUA had higher hypertension risk (HR=1.45, 95% CI 1.21 to 1.73), while no such association was observed in men. Stratified analyses revealed significant associations between elevated SUA levels and CVD risk factors in postmenopausal and non-obese women.

CONCLUSIONS

Elevated SUA levels increase the risk of dyslipidaemia in both sexes. SUA levels within normal range and HUA are positively associated with hyperglycaemia and hypertension in postmenopausal women, but not in men.

Effect of Alcohol Consumption Habits on Early Arterial Aging in Subjects with Metabolic Syndrome and Elevated Serum Uric Acid

BACKGROUND

Hyperuricemia is perceived as one of the risk factors for developing and progressing cardiovascular disease and metabolic syndrome through various pathological mechanisms. Endogenous synthesis and exogenous factors such as diet and beverages consumed play a major role in determining serum uric acid (sUA) levels. The aim of this study was to evaluate the effect of alcohol consumption on early arterial aging in middle-aged patients with metabolic syndrome (MetS) and hyperuricemia.

MATERIALS AND METHODS

This study included 661 middle-aged subjects (241 men and 420 women) from the Lithuanian High Cardiovascular Risk (LitHiR) primary prevention program. Characteristics of subjects such as blood pressure, laboratory testing, and the specialized nutrition profile questionnaire were evaluated. As an early marker of arterial stiffness, carotid-femoral pulse wave velocity (cfPWV) was assessed using a non-invasive applanation tonometry technique.

RESULTS

Hyperuricemia was present in 29% of men and 34% of women. Hyperuricemic men reported 1.6 times higher rates of alcohol drinking compared to men with normal sUA levels. After analyzing the correlation between alcohol consumption and cfPWV, no statistically significant relationships were found at a significance level of α = 0.05 but lowering the significance level to 0.06 revealed significant associations in men with normal sUA (ε2ordinal = 0.05, p = 0.06) and in women with increased sUA levels (ε2ordinal = 0.05, p = 0.08). Regression analysis showed that hyperuricemic men, consuming more than one unit of alcohol per week, had a significant impact on increasing cfPWV, while men with normal sUA levels, abstaining from alcohol entirely, resulted in a statistically significant decrease in cfPWV. Our results showed statistically significant relationships only among a group of men, although the women in the hyperuricemic group had a statistically higher cfPWV than women with normal sUA levels.

CONCLUSIONS

Drinking alcohol is associated with increased arterial stiffness among hyperuricemic middle-aged men with MetS.

Sexual Dimorphism in Cardiometabolic Diseases: The Role of AMPK

Cardiovascular diseases (CVDs) are the leading cause of mortality and disability among both males and females. The risk of cardiovascular diseases is heightened by the presence of a risk factor cluster of metabolic syndrome, covering obesity and obesity-related cardiometabolic risk factors such as hypertension, glucose, and lipid metabolism dysregulation primarily. Sex hormones contribute to metabolic regulation and make women and men susceptible to obesity development in a different manner, which necessitates sex-specific management. Identifying crucial factors that protect the cardiovascular system is essential to enhance primary and secondary prevention of cardiovascular diseases and should be explicitly studied from the perspective of sex differences. It seems that AMP-dependent protein kinase (AMPK) may be such a factor since it has the protective role of AMPK in the cardiovascular system, has anti-diabetic properties, and is regulated by sex hormones. Those findings highlight the potential cardiometabolic benefits of AMPK, making it an essential factor to consider. Here, we review information about the cross-talk between AMPK and sex hormones as a critical point in cardiometabolic disease development and progression and a target for therapeutic intervention in human disease.

The potential relationship of coronary artery disease and hyperuricemia: A cardiometabolic risk factor

Coronary arterial disease (CAD) is the leading cause of mortality in the world. Hyperuricemia has recently emerged as a novel independent risk factor of CAD, in addition to the traditional risk factors such as hyperlipidemia, smoking, and obesity. Several clinical studies have shown that hyperuricemia is strongly associated with the risk, progression and poor prognosis of CAD, as well as verifying an association with traditional CAD risk factors. Uric acid or enzymes in the uric acid production pathway are associated with inflammation, oxidative stress, regulation of multiple signaling pathways and the renin-angiotensin-aldosterone system (RAAS), and these pathophysiological alterations are currently the main mechanisms of coronary atherosclerosis formation. The risk of death from CAD can be effectively reduced by the uric acid-lowering therapy, but the interventional treatment of uric acid levels in patients with CAD remains controversial due to the diversity of co-morbidities and the complexity of causative factors. In this review, we analyze the association between hyperuricemia and CAD, elucidate the possible mechanisms by which uric acid induces or exacerbates CAD, and discuss the benefits and drawbacks of uric acid-lowering therapy. This review could provide theoretical references for the prevention and management of hyperuricemia-associated CAD.

Endothelial Cell Dysfunction and Increased Cardiovascular Risk in Patients With Chronic Kidney Disease

The endothelium is considered to be the gatekeeper of the vessel wall, maintaining and regulating vascular integrity. In patients with chronic kidney disease, protective endothelial cell functions are impaired due to the proinflammatory, prothrombotic and uremic environment caused by the decline in kidney function, adding to the increase in cardiovascular complications in this vulnerable patient population. In this review, we discuss endothelial cell functioning in healthy conditions and the contribution of endothelial cell dysfunction to cardiovascular disease. Further, we summarize the phenotypic changes of the endothelium in chronic kidney disease patients and the relation of endothelial cell dysfunction to cardiovascular risk in chronic kidney disease. We also review the mechanisms that underlie endothelial changes in chronic kidney disease and consider potential pharmacological interventions that can ameliorate endothelial health.

Association of serum uric acid to lymphocyte ratio, a novel inflammatory biomarker, with risk of stroke: A prospective cohort study

MAIN PROBLEM

Inflammation plays an important role in the pathological progress associated with stroke. Serum uric acid (SUA) to lymphocyte ratio (ULR), a novel inflammatory biomarker, has been considered as a better risk stratification tool of adverse outcomes than SUA or lymphocyte alone. This study aimed to investigate whether ULR produced more predictive value for stroke and explore the potential mediators of the associations.

METHODS

This study enrolled 93,023 Chinese participants without stroke and myocardial infarction at baseline. Cox proportional hazard models were used to analyze the associations of ULR with stroke and subtypes. Mediation analyses were conducted to explore potential mediators of the associations.

RESULTS

During a median follow-up of 13.00 years, 6081 cases of incident stroke occurred, including 5048 cases of ischemic stroke (IS) and 900 cases of hemorrhagic stroke (HS). After adjustment for confounders, the Q4 group was associated with a higher risk of HS (HR, 1.25; 95% CI, 1.03-1.50), but not with total stroke (HR, 1.07; 95% CI, 1.03-1.13) or IS (HR, 1.04; 95% CI, 0.97-1.12). No significant associations were found between SUA or lymphocyte and any stroke. ULR outperformed SUA or lymphocytes alone in predicting stroke. Additionally, the significant association between ULR and HS was partially mediated by systolic blood pressure (20.32%), diastolic blood pressure (11.18%) and estimated glomerular filtration rate (9.19%).

CONCLUSIONS

ULR was significantly associated with the risk of HS, but not with IS. Systolic blood pressure, diastolic blood pressure and estimated glomerular filtration rate were potential mediators for the association.

Serum growth differentiation factor-15 and non-esterified fatty acid levels in patients with coronary artery disease and hyperuricemia

BACKGROUND

High serum NEFA and GDF-15 are risk factors for CAD and have been linked to detrimental cardiovascular events. It has been hypothesized that hyperuricemia causes CAD via the oxidative metabolism and inflammation. The current study sought to clarify the relationship between serum GDF-15/NEFA and CAD in individuals with hyperuricemia.

METHODS

Blood samples collected from 350 male patients with hyperuricemia(191 patients without CAD and 159 patients with CAD, serum UA > 420 μmol/L) to measure serum GDF-15 and NEFA concentrations with baseline parameters.

RESULTS

Serum circulating GDF-15 concentrations(pg/dL) [8.48(6.67,12.73)] and NEFA levels(mmol/L) [0.45(0.32,0.60)] were higher in hyperuricemia patients with CAD. Logistic regression analysis revealed that the OR (95% CI) for CAD were 10.476 (4.158, 26.391) and 11.244 (4.740, 26.669) in quartile 4 (highest) respectively. The AUC of the combined serum GDF-15 and NEFA was 0.813 (0.767,0.858) as a predictor of whether CAD occurred in male with hyperuricemia.

CONCLUSIONS

Circulating GDF-15 and NEFA levels correlated positively with CAD in male patients with hyperuricemia and measurements may be a useful clinical adjunct.

Uric Acid Deteriorates Load-Free Cell Shortening of Cultured Adult Rat Ventricular Cardiomyocytes via Stimulation of Arginine Turnover

Hyperuricemia is a risk factor for heart disease. Cardiomyocytes produce uric acid via xanthine oxidase. The enzymatic reaction leads to oxidative stress in uric-acid-producing cells. However, extracellular uric acid is the largest scavenger of reactive oxygen species, specifically to nitrosative stress, which can directly affect cells. Here, the effect of plasma-relevant concentrations of uric acid on adult rat ventricular cardiomyocytes is analyzed. A concentration- and time-dependent reduction of load-free cell shortening is found. This is accompanied by an increased protein expression of ornithine decarboxylase, the rate-limiting enzyme of the polyamine metabolism, suggesting a higher arginine turnover. Subsequently, the effect of uric acid was attenuated if other arginine consumers, such as nitric oxide synthase, are blocked or arginine is added. In the presence of uric acid, calcium transients are increased in cardiomyocytes irrespective of the reduced cell shortening, indicating calcium desensitization. Supplementation of extracellular calcium or stimulation of intracellular calcium release by β-adrenergic receptor stimulation attenuates the uric-acid-dependent effect. The effects of uric acid are attenuated in the presence of a protein kinase C inhibitor, suggesting that the PKC-dependent phosphorylation of troponin triggers the desensitizing effect. In conclusion, high levels of uric acid stress cardiomyocytes by accelerating the arginine metabolism via the upregulation of ornithine decarboxylase.

Hyperuricemia and Endothelial Function: Is It a Simple Association or Do Gender Differences Play a Role in This Binomial?

The endothelium plays a fundamental role in the biological processes that ensure physiological vessel integrity, synthesizing numerous substances that are capable of modulating the tone of vessels, inflammation and the immune system, and platelet function. Endothelial dysfunction refers to an anomaly that develops at the level of the tunica that lines the internal surface of arterial and venous vessels, or, more precisely, an alteration to normal endothelial function, which involves the loss of some structural and/or functional characteristics. Studies on sex differences in endothelial function are conflicting, with some showing an earlier decline in endothelial function in men compared to women, while others show a similar age of onset between the sexes. Since increased cardiovascular risk coincides with menopause, female hormones, particularly estrogen, are generally believed to be cardioprotective. Furthermore, it is often proposed that androgens are harmful. In truth, these relationships are more complex than one might think and are not just dependent on fluctuations in circulating hormones. An increase in serum uric acid is widely regarded as a possible risk factor for cardiovascular disease; however, its role in the occurrence of endothelial dysfunction has not yet been elucidated. Several studies in the literature have evaluated sex-related differences in the association between elevated uric acid levels and cardiovascular events, with conflicting results. The association between uric acid and cardiovascular disease is still controversial, and it is not yet clear how gender differences affect the serum concentration of these substances. This review was primarily aimed at clarifying the effects of uric acid at the level of the vascular endothelium and describing how it could theoretically cause damage to endothelial integrity. The second aim was to determine if there are gender differences in uric acid metabolism and how these differences interact with the vascular endothelium.

Cellular Senescence in Metabolic-Associated Kidney Disease: An Update

Cellular senescence is described as the state where the cell cycle is arrested irreversibly, which occurs in response to various forms of stress factors in cells, leading to the senescence-associated secretory phenotype (SASP). We can assess the accumulation of senescent cells in tissues or organs through biomarkers of cellular senescence such as p16INK4a, p53, p21, and SA-β-GAL. In recent decades, a large number of studies have reported the biomarkers of increased cell senescence in pathogenic tissues, demonstrating the possible connection between cell senescence and various diseases. Kidney damage often occurs in the pathophysiological process of certain metabolic diseases, resulting in metabolic-associated kidney diseases. For example, hypertension causes systemic arteriosclerosis, and the kidney can be seriously affected by abundant blood vessels, which may lead to a decreased glomerular filtration rate (GFR) and proteinuria, resulting in hypertension-related kidney diseases. The accumulation of senescent cells may also be observed in some metabolic-associated kidney diseases (such as obesity-related nephropathy, hypertension-related nephropathy, and diabetic nephropathy). In this paper, we review existing knowledge regarding the influence of cellular senescence on metabolic-associated kidney diseases, providing new ideas for future treatment.

Uric Acid to High-Density Lipoprotein Cholesterol Ratio is a Novel Marker to Predict Functionally Significant Coronary Artery Stenosis

Background

Intermediate coronary stenosis (ICS) is defined as a visually estimated percentage of diameter stenosis ranging between 40% and 70% by conventional coronary angiography (CAG). Whether to perform percutaneous coronary intervention (PCI) for these lesions is a challenge in clinical practice. The fractional flow reserve (FFR) can guide treatment by determining the functional significance of ICS. Studies have shown that some clinical indicators can be used to predict FFR. However, there is little research on this in the Chinese population.

Methods

We retrospectively analyzed 690 patients who underwent FFR measurements to determine the functional significance of a single ICS. Patients were divided into 2 groups: FFR ≤0.8 (n = 280) and FFR >0.8 (n = 410). We compared the clinical factors between the two groups and performed multivariate logistic regression analyses to explore the risk factors. In addition, receiver-operating characteristic (ROC) curves were constructed for FFR ≤0.8 diagnoses.

Results

The mean UHR (uric acid to high-density lipoprotein cholesterol ratio) level was significantly higher in the FFR ≤0.8 group (p < 0.001). UHR corrects negatively with FFR (r = −0.44, p < 0.001). High-level UHR was an independent risk factor for the FFR ≤0.8 (OR = 7.17, 95% CI 4.17–12.34). The area under the curve (AUC) of the UHR diagnostic capacity for the FFR ≤0.8 is 0.77, with 77.3% sensitivity and 68.2% specificity.

Conclusion

UHR levels were significantly increased in patients with hemodynamically significant coronary lesions. UHR is a novel predictor of functionally significant lesions in patients with a single-vessel disease of ICS.

Mutual effect of homocysteine and uric acid on arterial stiffness and cardiovascular risk in the context of predictive, preventive, and personalized medicine

Background

Arterial stiffness is a major risk factor and effective predictor of cardiovascular diseases and a common pathway of pathological vascular impairments. Homocysteine (Hcy) and uric acid (UA) own the shared metabolic pathways to affect vascular function. Serum uric acid (UA) has a great impact on arterial stiffness and cardiovascular risk, while the mutual effect with Hcy remains unknown yet. This study aimed to evaluate the mutual effect of serum Hcy and UA on arterial stiffness and 10-year cardiovascular risk in the general population. From the perspective of predictive, preventive, and personalized medicine (PPPM/3PM), we assumed that combined assessment of Hcy and UA provides a better tool for targeted prevention and personalized intervention of cardiovascular diseases via suppressing arterial stiffness.

Methods

This study consisted of 17,697 participants from Beijing Health Management Cohort, who underwent health examination between January 2012 and December 2019. Brachial-ankle pulse wave velocity (baPWV) was used as an index of arterial stiffness.

Results

Individuals with both high Hcy and UA had the highest baPWV, compared with those with low Hcy and low UA (β: 30.76, 95% CI: 18.36-43.16 in males; β: 53.53, 95% CI: 38.46-68.60 in females). In addition, these individuals owned the highest 10-year cardiovascular risk (OR: 1.49, 95% CI: 1.26-1.76 in males; OR: 7.61, 95% CI: 4.63-12.68 in females). Of note, males with high homocysteine and low uric acid were significantly associated with increased cardiovascular risk (OR: 1.30, 95% CI: 1.15-1.47), but not the high uric acid and low homocysteine group (OR: 1.02, 95% CI: 0.90-1.16).

Conclusions

This study found the significantly mutual effect of Hcy and UA on arterial stiffness and cardiovascular risk using a large population and suggested the clinical importance of combined evaluation and control of Hcy and UA for promoting cardiovascular health. The adverse effect of homocysteine on arteriosclerosis should be addressed beyond uric acid, especially for males. Monitoring of the level of both Hcy and UA provides a window opportunity for PPPM/3PM in the progression of arterial stiffness and prevention of CVD. Hcy provides a novel predictor beyond UA of cardiovascular health to identify individuals at high risk of arterial stiffness for the primary prevention and early treatment of CVD. In the progressive stage of arterial stiffness, active control of Hcy and UA levels from the aspects of dietary behavior and medication treatment is conducive to alleviating the level of arterial stiffness and reducing the risk of CVD. Further studies are needed to evaluate the clinical effect of Hcy and UA targeted intervention on arterial stiffness and cardiovascular health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00298-x.

Uric acid in metabolic syndrome: Does uric acid have a definitive role?

Increased serum uric acid (SUA) levels are commonly seen in patients with metabolic syndrome and are widely accepted as risk factors for hypertension, gout, non-alcoholic fatty liver disease, chronic kidney disease (CKD), and cardiovascular diseases. Although some ambiguity for the exact role of uric acid (UA) in these diseases is still present, several pathophysiological mechanisms have been identified such as increased oxidative stress, inflammation, and apoptosis. Accumulating evidence in genomics enlightens genetic variabilities and some epigenetic changes that can contribute to hyperuricemia. Here we discuss the role of UA within metabolism and the consequences of asymptomatic hyperuricemia while providing newfound evidence for the associations between UA and gut microbiota and vitamin D. Increased SUA levels and beneficial effects of lowering SUA levels need to be elucidated more to understand its complicated function within different metabolic pathways and set optimal target levels for SUA for reducing risks for metabolic and cardiovascular diseases.

Hyperuricemia, a Non-Independent Component of Metabolic Syndrome, Only Predicts Renal Outcome in Chronic Kidney Disease Patients without Metabolic Syndrome or Diabetes

Uric acid (UA) is elevated in metabolic syndrome (MS) and diabetes (DM). UA is associated with central obesity and blood glucose and is proposed as a criterion of MS. Previous reports showed that UA could predict renal outcome in CKD. However, recent clinical trials did not demonstrate the benefits of urate-lowering agents (ULA) for renal outcome. Whether the prognostic value of UA for renal outcome is independent of MS or secondary to MS in CKD patients is unknown. Our study included 2500 CKD stage 1−4 Asian patients divided by UA tertiles and MS/DM. In linear regression, UA was associated with obesity, C-reactive protein, and renal function. In Cox regression, high UA was associated with worse renal outcome in non-MS/DM, but not in MS/DM: hazard ratio (95% confidence interval) of UA tertile 3 was 3.86 (1.87−7.97) in non-MS/DM and 1.00 (0.77−1.30) in MS/DM (p for interaction < 0.05). MS was associated with worse renal outcome, but redefined MS (including hyperuricemia as the 6th criteria) was not. In conclusion, hyperuricemia is associated with worse renal outcome in non-MS/DM and is not an independent component of MS in CKD stage 1−4 patients. Hyperuricemia secondary to MS could not predict renal outcome.

Uric Acid Reacts with Peroxidasin, Decreases Collagen IV Crosslink, Impairs Human Endothelial Cell Migration and Adhesion

Uric acid is considered the main substrate for peroxidases in plasma. The oxidation of uric acid by human peroxidases generates urate free radical and urate hydroperoxide, which might affect endothelial function and explain, at least in part, the harmful effects of uric acid on the vascular system. Peroxidasin (PXDN), the most recent heme-peroxidase described in humans, catalyzes the formation of hypobromous acid, which mediates collagen IV crosslinks in the extracellular matrix. This enzyme has gained increasing scientific interest since it is associated with cardiovascular disease, cancer, and renal fibrosis. The main objective here was to investigate whether uric acid would react with PXDN and compromise the function of the enzyme in human endothelial cells. Urate decreased Amplex Red oxidation and brominating activity in the extracellular matrix (ECM) from HEK293/PXDN overexpressing cells and in the secretome of HUVECs. Parallelly, urate was oxidized to 5-hydroxyisourate. It also decreased collagen IV crosslink in isolated ECM from PFHR9 cells. Urate, the PXDN inhibitor phloroglucinol, and the PXDN knockdown impaired migration and adhesion of HUVECs. These results demonstrated that uric acid can affect extracellular matrix formation by competing for PXDN. The oxidation of uric acid by PXDN is likely a relevant mechanism in the endothelial dysfunction related to this metabolite.

Research progress on related mechanisms of uric acid activating NLRP3 inflammasome in chronic kidney disease

Hyperuricemia is an independent risk factor for the progression of chronic kidney disease. High levels of uric acid can lead to a series of pathological conditions, such as gout, urinary stones, inflammation, and uric acid nephropathy. There is a close relationship between uric acid and the NLRP3 inflammasome. NLRP3 inflammasome activation can cause cell damage and even death through endoplasmic reticulum stress, lysosome destruction, mitochondrial dysfunction, and the interaction between the Golgi apparatus and extracellular vesicles. In addition, the NLRP3 inflammasome acts as a molecular platform, triggering the activation of caspase-1 and the lysis of IL-1β, IL-18 and Gasdermin D (GSDMD) through different molecular mechanisms. Cleaved NT-GSDMD forms pores in the cell membrane and triggers pyrophosphorylation, thereby inducing cell death and releasing many intracellular proinflammatory molecules. In recent years, studies have found that hyperuricemia or uric acid crystals can activate NLRP3 inflammasomes, and the activation of NLRP3 inflammasomes plays an important role in kidney disease. This article reviews the possible pathophysiological mechanisms by which uric acid activates inflammasomes and induces kidney damage at the cellular and molecular levels.

U-Shaped Association Between Serum Uric Acid and Hemorrhagic Transformation After Intravenous Thrombolysis

BACKGROUND

Uric acid (UA) has both antioxidative and pro-oxidative properties. The study aimed to investigate the relationship between serum UA and hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke.

METHODS

The patients undergoing intravenous thrombolysis from two hospitals in China were retrospectively analyzed. HT was evaluated using computed tomography images reviewed within 24- 36h after thrombolysis. Symptomatic intracranial hemorrhage (sICH) was defined as HT accompanied by worsening neurological function. Multivariate logistic regression and spline regression models were performed to explore the relationship between serum UA levels and the risk of HT and sICH.

RESULTS

Among 503 included patients, 60 (11.9%) were diagnosed with HT and 22 (4.4%) developed sICH. Patients with HT had significant lower serum UA levels than those without HT (245 [214-325 vs. 312 [256-370] μmol/L, p < 0.001). Multivariable logistic regression analysis indicated that patients with higher serum UA levels had a lower risk of HT (OR per 10-μmol/L increase 0.96, 95%CI 0.92-0.99, p = 0.015). Furthermore, multiple-adjusted spline regression models showed a Ushaped association between serum UA levels and HT (p < 0.001 for non-linearity). Similar results were present between serum UA and sICH. Restricted cubic spline models predicted the lowest risk of HT and sICH when the serum UA levels were 386μmol/L.

CONCLUSION

The data show the U-shaped relationship between serum UA levels and the risk of HT and sICH after intravenous thrombolysis.

Hyperuricaemia is an important risk factor of the erectile dysfunction: A systematic review and meta-analysis

Serum uric acid can affect endothelial function, and hyperuricaemia-induced endothelial dysfunction is involved in the pathogenesis of cardiovascular diseases. As endothelial dysfunction is also a main pathogenic mechanism of erectile dysfunction (ED), the present study aims to evaluate the relationship between hyperuricaemia and ED via systemic review and meta-analysis. Five cohort studies and six cross-sectional studies on hyperuricaemia and ED, including a total of 454,510 participants, were recruited. Odds ratio (OR) and the 95% confidence intervals (CI) were adopted to estimate the relationship between hyperuricaemia and ED. Overall risk on effects of urate-lowering therapy (ULT) were analysed. In addition, subgroup analyses on study design, populations, age stratification and the object were conducted. In the patients with hyperuricaemia, the risk of ED was 1.59-fold higher than (pooled OR = 1.59, 95% CI [1.29, 1.97]) the non-hyperuricaemia counterparts. Urate-lowing therapy (ULT) in these hyperuricaemia patients reduced the risk of ED by 27% (OR = 1.27, 95% CI [1.14, 1.41]). After subgroup analysis, the association between hyperuricaemia and ED remained significant apart from the >60 years subgroup. Hyperuricaemia is an important risk factor of ED, while ULT can reduce the risk of ED in hyperuricaemia. This study suggests that hyperuricaemia-associated endothelial dysfunction may also underlie the pathogenesis of ED in these patients.

Prognostic value of hyperuricemia for patients with sepsis in the intensive care unit

This study evaluated the relationship between hyperuricemia at admission and the clinical prognosis of patients with sepsis. The data were obtained from the Intensive Care Medical Information Database III. The patients were divided into a normal serum uric acid group and a hyperuricemia group. The main outcome was 90-day mortality, and the secondary outcomes were hospital mortality, 30-day mortality, and acute kidney injury. Propensity score matching was used to balance the baseline characteristics of the groups. Our study retrospectively included 954 patients. Before and after propensity score matching, the incidence of AKI, the 30-day and 90-day mortality rates were significantly higher in the hyperuricemia group. Cox regression analysis showed that hyperuricemia was significantly associated with 90-day mortality (HR 1.648, 95% CI 1.215–2.234, p = 0.006), and hyperuricemia was significantly associated with the incidence of AKI (HR 1.773, 95% CI 1.107–2.841, p = 0.017). The Kaplan–Meier survival curve showed that the 90-day survival rate was significantly lower in the hyperuricemia group. In patients with sepsis in the intensive care unit, hyperuricemia was significantly associated with increased risk 90-day all-cause mortality and the incidence of AKI.

Impact of serum uric acid levels on the clinical prognosis and severity of coronary artery disease in patients with acute coronary syndrome and hypertension after percutaneous coronary intervention: a prospective cohort study

OBJECTIVE

The impact of serum uric acid (sUA) levels on the clinical prognosis and severity of coronary artery disease in patients with acute coronary syndrome (ACS) and hypertension after percutaneous coronary intervention (PCI) is not fully clear. This study aimed to assess the association among sUA levels, clinical prognosis and severity of coronary artery disease in patients with ACS and hypertension after PCI.

DESIGN

In this prospective cohort study, we followed-up patients with ACS and hypertension after PCI for 1 year to explore the risk factors for 1 year total major adverse cardiovascular events (MACEs) and multivessel coronary artery disease, the dose-effect relationship among sUA levels, MACEs and severity of coronary artery disease and correlation between sUA levels and severity of coronary artery disease (Gensini score).

SETTING/PATIENTS

Several Chinese internists followed-up 422 patients who were diagnosed with ACS and hypertension after PCI in a large tertiary hospital of Qingdao during the period from 1 June 2019 to 1 December 2019.

OUTCOME MEASURES

One-year follow-up MACEs results and coronary angiography results.

RESULTS

In the coronary angiography results, multivessel coronary artery disease (28.5% vs 21.4%, p=0.006) and non-culprit lesion vascular occlusion (11.7% vs 5.3%, p=0.042) were more common in the hyperuricaemia group, and the Gensini score (26.69±13.46 vs 17.66±10.57, p<0.001) was also higher. In the results of 1-year MACEs, the incidence of all-cause mortality (3.5% vs 2.5%, p=0.037), PCI or coronary artery bypass grafting therapy due to myocardial infarction or angina pectoris (15.1% vs 7.6%, p=0.027), medication conservative therapy in hospital due to myocardial infarction or angina pectoris (12.9% vs 6.7%, p=0.041) and total MACEs (31.8% vs 16.9%, p=0.001) were higher in patients with hyperuricaemia. Univariate and multivariate logistic regression analysis models showed that hyperuricaemia was still an independent risk factor for total MACEs within 1 year (OR=2.618, 95% CI 1.656 to 4.139, p<0.001; OR=1.920, 95% CI 1.158 to 3.183, p=0.011, respectively) and multivessel coronary artery disease (OR=2.140, 95% CI 1.371 to 3.342, p=0.001; OR=1.688, 95% CI 1.051 to 2.710, p=0.030, respectively) after adjusting for confounding factors. The severity of coronary artery disease (non-culprit lesion vascular occlusion (4.7% vs 8.4% vs 9.6% vs 16.2%, p=0.041); multivessel coronary artery disease (17.9% vs 22.4% vs 29.8% vs 35.2%, p=0.022); Gensini score (16.96±10.35 vs 19.31±10.63 vs 26.12±11.48 vs 33.33±14.01, p<0.001)) and the incidence of total MACEs (13.2% vs 14.2% vs 34.6% vs 41%, p<0.001) increased significantly with the sUA levels increasing. Further, the Gensini score was positively correlated with uric acid levels (r=0.515, p<0.001).

CONCLUSIONS

Hyperuricaemia is an independent risk factor for 1-year total MACEs and multivessel coronary artery disease in patients with ACS and hypertension after PCI.

Impact of Uremic Toxins on Endothelial Dysfunction in Chronic Kidney Disease: A Systematic Review

Patients with chronic kidney disease (CKD) are at a highly increased risk of cardiovascular complications, with increased vascular inflammation, accelerated atherogenesis and enhanced thrombotic risk. Considering the central role of the endothelium in protecting from atherogenesis and thrombosis, as well as its cardioprotective role in regulating vasorelaxation, this study aimed to systematically integrate literature on CKD-associated endothelial dysfunction, including the underlying molecular mechanisms, into a comprehensive overview. Therefore, we conducted a systematic review of literature describing uremic serum or uremic toxin-induced vascular dysfunction with a special focus on the endothelium. This revealed 39 studies analyzing the effects of uremic serum or the uremic toxins indoxyl sulfate, cyanate, modified LDL, the advanced glycation end products N-carboxymethyl-lysine and N-carboxyethyl-lysine, p-cresol and p-cresyl sulfate, phosphate, uric acid and asymmetric dimethylarginine. Most studies described an increase in inflammation, oxidative stress, leukocyte migration and adhesion, cell death and a thrombotic phenotype upon uremic conditions or uremic toxin treatment of endothelial cells. Cellular signaling pathways that were frequently activated included the ROS, MAPK/NF-κB, the Aryl-Hydrocarbon-Receptor and RAGE pathways. Overall, this review provides detailed insights into pathophysiological and molecular mechanisms underlying endothelial dysfunction in CKD. Targeting these pathways may provide new therapeutic strategies reducing increased the cardiovascular risk in CKD.

Serum Uric Acid to Serum Creatinine Ratio and Risk of Stroke Recurrence in Young Adults with Ischemic Stroke

BACKGROUND AND AIM

Serum uric acid to serum creatinine ratio (SUA/SCr) is associated with metabolic and cardiovascular diseases. We aimed to investigate the association between SUA/SCr and stroke recurrence among young adults with ischemic stroke.

METHODS

A total of 428 young patients with ischemic stroke were included in the present study. SUA/SCr was calculated from the concentration of serum uric acid and creatine (uric acid/creatine). Cox proportional regression models were performed to evaluate the association between SUA/SCr and stroke recurrence. Kaplan-Meier curves were used to compare recurrence rates in different quantiles of SUA/SCr.

RESULTS

During a median follow-up of 3.14 years, 51 (10.7%) patients had stroke recurrence. Multivariable analyses indicated that SUA/SCr was associated with stroke recurrence after being adjusted for potential confounders (quantile four versus quantile one: hazard ratio: 3.420; 95% confidence interval: 1.426-8.200; P = 0.006). Kaplan-Meier curves revealed that patients with a high concentration of SUA/SCr had an increased stroke recurrence risk. The time-dependent receiver operating characteristic curve showed that the area under the curve for SUA/SCr was above 0.7 during follow-up. Restricted cubic spline presented an increasing trend for the link between SUA/SCr and stroke recurrence among young adults.

CONCLUSION

SUA/SCr was positively associated with the risk of stroke recurrence among young adults with ischemic stroke. Further prospective studies are warranted to assess the causality between SUA/SCr and the development of stroke recurrence among young adults.

Hyperuricemia is Associated With 2- and 5-Year Adverse Outcomes in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention

BACKGROUND

Hyperuricemia has recently been identified as a risk factor of cardiovascular diseases; however, prognostic value of hyperuricemia in patients with ST-segment elevation myocardial infarction (STEMI) remained unclear. Simultaneously, the mechanism of this possible relationship has not been clarified. At present, some views believe that hyperuricemia may be related to the inflammatory response. Our study aimed to investigate the association between hyperuricemia and long-term poor prognosis and inflammation in STEMI patients undergoing percutaneous coronary intervention (PCI).

METHODS

A total of 1,448 consecutive patients with STEMI were studied throughout 2013 at a single center. The primary endpoint was all-cause death at 2- and 5-year follow-up. Inflammatory biomarkers were collected on admission of those patients: high sensitive C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count.

RESULTS

Hyperuricemia was associated with higher 2- and 5-year all-cause death in STEME patients compared to normouricemia (5.5% vs. 1.4%, P <0.001; 8.0% vs 3.9%, P = 0.004; respectively). After multivariable adjustment, hyperuricemia was still an independent predictor of 2-year all-cause death (hazard ratio (HR) =4.332, 95% confidence interval (CI): 1.990-9.430, P <0.001) and 5-year all-cause death (HR =2.063, 95% CI: 1.186-3.590, P =0.010). However, there was no difference in hs-CRP, ESR, and WBC count on admission in STEMI patients with hyperuricemia compared to normouricemia (P >0.05).

CONCLUSIONS

Hyperuricemia was associated with higher risks of 2- and 5-year all-cause deaths in patients with STEMI undergoing PCI. However, this study did not find a correlation between hyperuricemia and inflammatory responses in newly admitted STEMI patients.

Hyperuricemia and Associated Factors in Children with Chronic Kidney Disease: A Cross-Sectional Study

Background: Hyperuricemia is increasingly recognized as a risk factor for chronic kidney disease (CKD) just in adults. The purpose of this study was to investigate the clinical characteristics of hyperuricemia and its associated factors in Chinese children with CKD at a single center. Methods: A cross-sectional study of 170 CKD children collected from the Department of Nephrology, The Zhejiang University Children’s Hospital was conducted. The clinical data, including anthropometric data, blood pressure measurements, and biochemical parameters, were recorded and analyzed retrospectively. The factors associated with hyperuricemia in CKD children were evaluated by Pearson and Spearman correlation analysis and multiple logistic regression analysis. Results: The mean age was 9.79 ± 4.10 years, and 72 (42.35%) were girls. Higher blood urea nitrogen (BUN), serum creatinine, cystatin C, D-dimer, lower hemoglobin, albumin, and estimated glomerular filtration rate (eGFR) were significantly associated with higher serum uric acid (SUA). In multiple logistic regression analysis, anemia and higher BUN were both positively associated factors, whereas eGFR ≥ 90 mL/min/1.73 m² was a negatively associated factor for subjects with SUA ≥ 390 µmol/L (6.5 mg/dL). Conclusions: SUA was significantly associated with kidney risk factors in CKD children. Monitoring and controlling SUA, Hb, BUN, and Scr levels in CKD children may help to prevent the progression of CKD.

The effects of hyperuricemia on endothelial cells are mediated via GLUT9 and the JAK2/STAT3 pathway

BACKGROUND

Uric acid (UA) transporters mediate the uptake and outflow of UA, and are greatly involved in the control of UA concentrations. Glucose transporter 9 (GLUT9), one of the UA transporters, has been confirmed to be expressed in human umbilical vein endothelial cells (HUVECs). This study aimed to characterize GLUT9's effect on intracellular UA accumulation in HUVECs in a high-UA environment and to explore the mechanism of cellular dysfunction.

METHODS AND RESULTS

HUVECs were treated with UA to establish a model of cellular dysfunction. Then, UA uptake, GLUT9 expression and endothelial nitric oxide synthase (eNOS) and reactive oxygen species (ROS) amounts were measured. UA uptake was concentration- and time-dependent, and UA treatment significantly reduced nitric oxide (NO) levels and eNOS activity. UA also upregulated pro-inflammatory molecules and GLUT9, and increased intracellular ROS amounts in HUVECs. GLUT9 knockdown reduced UA uptake and ROS content, but antioxidant treatment did not reduce GLUT9 expression. To assess the function of JAK2/STAT3 signaling, HUVECs were treated with UA, and the phosphorylation levels of JAK2, STAT3, IL-6 and SOCS3 were increased by a high concentration of UA. In addition, GLUT9 knockdown reduced the phosphorylation of JAK2/STAT3 intermediates and increased p-eNOS amounts.

CONCLUSIONS

GLUT9 mediated the effects of high UA levels on HUVECs by increasing the cellular uptake of UA, activating JAK2/STAT3 signaling, and reduced the production of active eNOS and NO in HUVECs.

Individual and combined association analysis of famine exposure and serum uric acid with hypertension in the mid-aged and older adult: a population-based cross-sectional study

Background

Malnutrition in early life may affect health in later life. The associations between malnutrition and serum uric acid (SUA) and hypertension were inconsistent. The present study aimed to investigate the individual and combined association between famine exposure and serum uric acid and hypertension in middle-aged and older Chinese.

Methods

Data were selected from the China Health and Retirement Longitudinal Study (CHARLS) Wave2011. The analytic sample included 9368 individuals aged 45 to 90. Differences between baseline characteristics and famine exposure/SUA level were evaluated using the Chi-square test, t-test, and F-test. Then, the differences in the prevalence of hypertension between characteristic groups was also estimated by the Chi-square and t-test. Finally, multivariable-adjusted logistic regression models examined association of famine exposure and serum uric acid with odds of prevalence of hypertension.

Results

A total of 9368 individuals were enrolled in the study, 4366 (46.61%) and 5002 (53.39%) were male and female, respectively. Among males, 459 (10.51%) had been exposed to the Chinese famine during the fetal stage, whereas 1760 (40.31%) and 1645 (37.68%) had been exposed to the famine during childhood and adolescence/adult stage, respectively. Among females, 635 (12.69%) had been exposed to the Chinese famine during the fetal stage, whereas 1988 (39.74%) and 1569 (31.37%) had been exposed to the famine during childhood and adolescence/adult stage, respectively. Regarding the participants with SUA level measurements, 290 (6.64%) reported having Hyperuricemia (HUA) in males and 234 (4.68%) in the females. Furthermore, 1357 (31.08%) reported having hypertension in male and 1619 (32.37%) in the female. In multivariable-adjusted model, famine exposure and serum uric acid were associated with prevalence of hypertension independently in total populations [(1) Model four^d, fatal exposed group vs non-exposed group: 1.25 (95% CI 1.03, 1.52); childhood-exposed group vs non-exposed group:1.60 (95% CI 1.37, 1.87); adolescence/adult exposed group vs non-exposed group: 2.87 (95% CI 2.44, 3.37), P for trend < 0.001; (2) Model four ^e, high vs normal:1.73 (95% CI 1.44, 2.08)]. When stratified by sex, the results in both males and females were similar to those in the total population. In general, interaction analysis in the multivariable-adjusted model, compared with the combination of normal SUA level and no-exposed famine stage, all groups trended towards higher odds of prevalence of hypertension [the greatest increase in odds, adolescence/adult exposed stage and high SUA level in total participants: OR4.34; 95%CI 3.24, 5.81; P for interaction < 0.001]. When stratified by sex, the results in both males and females were also similar to those in the total population.

Conclusion

Our data support a strongly positive individual and combined association of famine exposure and serum uric acid with hypertension in middle-aged and elderly Chinese.

Hyperuricemia-induced endothelial insulin resistance: the nitric oxide connection

Hyperuricemia, defined as elevated serum concentrations of uric acid (UA) above 416 µmol L^-1, is related to the development of cardiometabolic disorders, probably via induction of endothelial dysfunction. Hyperuricemia causes endothelial dysfunction via induction of cell apoptosis, oxidative stress, and inflammation; however, it's interfering with insulin signaling and decreased endothelial nitric oxide (NO) availability, resulting in the development of endothelial insulin resistance, which seems to be a major underlying mechanism for hyperuricemia-induced endothelial dysfunction. Here, we elaborate on how hyperuricemia induces endothelial insulin resistance through the disruption of insulin-stimulated endothelial NO synthesis. High UA concentrations decrease insulin-induced NO synthesis within the endothelial cells by interfering with insulin signaling at either the receptor or post-receptor levels (i.e., proximal and distal steps). At the proximal post-receptor level, UA impairs the function of the insulin receptor substrate (IRS) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) in the insulin signaling pathway. At the distal level, high UA concentrations impair endothelial NO synthase (eNOS)-NO system by decreasing eNOS expression and activity as well as by direct inactivation of NO. Clinically, UA-induced endothelial insulin resistance is translated into impaired endothelial function, impaired NO-dependent vasodilation, and the development of systemic insulin resistance. UA-lowering drugs may improve endothelial function in subjects with hyperuricemia.

Gout-induced endothelial impairment: The role of SREBP2 transactivation of YAP

Gout is a multifaceted inflammatory disease involving vascular impairments induced by hyperuricemia. Experiments using human umbilical vein endothelial cells treated with uric acid (UA), monosodium urate (MSU), or serum from gout patients showed increased expression of pro-inflammatory genes (ie, VCAM1, ICAM1, CYR61, CCNA1, and E2F1) with attendant increase in monocyte adhesion. Mechanistically, UA- or MSU-induced SREBP2 expression and its transcriptional activity. RNA sequencing analysis and real-time PCR showed the induction of YAP signaling and pro-inflammatory pathways in HUVECs transfected with adenovirus-SREBP2. The SREBP2 knockdown by siRNA partially abolished UA- or MSU-induced YAP activity, pro-inflammatory gene expression, and monocytes adhesion. Vascular intima from transgenic mice overexpressing SREBP2 in endothelium or mice with hyperuricemia exhibited activated YAP signaling and increased expression of pro-inflammatory genes. Betulin, an SREBP pharmacological inhibitor, attenuated the UA-, MSU-, or gout serum-induced endothelial cell inflammation and dysfunction. In the human study, endothelial cell function, assessed by EndoPAT, was negatively correlated with serum UA level among gouty patients and healthy controls. Collectively, UA or MSU causes endothelial dysfunction via SREBP2 transactivation of YAP. Betulin inhibition of SREBP2 may restrain gout-induced endothelial dysfunction.

Gout Augments the Risk of Cardiovascular Disease in Patients With Psoriasis: A Population-Based Cohort Study

Objective

Patients with psoriasis (PsO) have a high frequency of concomitant gout and increased risk of cardiovascular diseases (CVD). We aimed to estimate the synergistic impact of gout on the risk of CVD in patients with PsO.

Methods

A population-based cohort of patients registered in the National Health Insurance Research Database of Taiwan between 2000 and 2013 was stratified according to the presence of PsO and gout. Propensity score analysis was used to match age and gender at a ratio of 1:4. Cox proportional hazard models and subgroup analyses were used to estimate the hazard ratios (HRs) for CVD adjusted for traditional risk factors. The Kaplan–Meier method was used to plot the cumulative incidence curves.

Results

Patients with combined PsO and gout (n = 97), PsO alone (n = 388), gout alone (matched, n = 388) and matched controls (n = 388) were identified. Compared with the patients with PsO alone, the patients with combined PsO and gout had a significantly higher risk of CVD (relative risk 2.39, 95% CI 1.56 to 3.65). After adjustment for traditional risk factors, the risk of CVD was higher in patients with gout alone (HR 2.16, 95% CI 1.54 to 3.04) and in patients with combined PsO and gout (HR 2.72, 95% CI 1.73 to 4.28).

Conclusions

Gout augments the risk of CVD independently of traditional risk factors in patients with PsO.

Cardiac abnormalities after induction of endoplasmic reticulum stress are associated with mitochondrial dysfunction and connexin43 expression

The endoplasmic reticulum (ER) is responsible for protein synthesis and calcium storage. ER stress, reflected by protein unfolding and calcium handling abnormalities, has been studied as a pathogenic factor in cardiovascular diseases. The aim of this study is to examine the effects of ER stress on mechanical and electrophysiological functions in the heart and explore the underlying molecular mechanisms. A total of 30 rats were randomly divided into control, ER stress inducer (tunicamycin[TN]) and ER stress inhibitor (tunicamycin+4-phenylbutyric acid [4-PBA]) groups. ER stress induction led to significantly systolic and diastolic dysfunction as reflected by maximal increasing/decreasing rate of left intraventricular pressure (±dp/dt), left ventricular peaksystolic pressure(LVSP) and LV end-diastolic pressure(LVEDP). Epicardial mapping performed in vivo revealed reduced conduction velocity and increased conduction heterogeneity associated with the development of spontaneous ventricular tachycardia. Masson's trichrome staining revealed marked fibrosis in the myocardial interstitial and sub-pericardial regions, and thickened epicardium. Western blot analysis revealed increased pro-fibrotic factor transforming growth factor-β1 (TGF-β1), decreased mitochondrial biogenesis protein peroxlsome proliferator-activated receptor-γ coactlvator-1α （PGC-1a）, and decreased mitochondrial fusion protein mitofusin-2 (MFN2). These changes were associated with mitochondria dysfunction and connexin 43(CX43)translocation to mitochondria. These abnormalities can be partially prevented by the ER stress inhibitor 4-PBA. Our study shows that ER stress induction can produce cardiac electrical and mechanism dysfunction as well as structural remodelling. Mitochondrial function alterations are contributed by CX43 transposition to mitochondria. These abnormalities can be partially prevented by the ER stress inhibitor 4-PBA.

Association between Serum Uric Acid and Pre-hypertension and Hypertension among Chinese Adults

Fundamento

O ácido úrico (AU), produto final do metabolismo dos nucleotídeos das purinas, participa dos processos de doenças metabólicas e cardiovasculares. Evidências experimentais sugerem que o ácido úrico é um mediador importante na resposta fisiológica ao aumento da pressão arterial.

Objetivo

Avaliar a associação entre os níveis séricos de AU e pré-hipertensão e hipertensão em uma população chinesa.

Métodos

Conduziu-se um estudo transversal entre março e setembro de 2017, e 1.138 participantes com idades entre 35 e 75 anos foram incluídos neste estudo, onde 223 normotensos, 316 pré-hipertensos e 599 hipertensos foram selecionados para avaliar a associação entre níveis séricos de AU e hipertensão. Considerou-se um valor de p<0,05 estatisticamente significativo.

Resultados

Os níveis séricos de AU foram significativamente maiores no grupo pré-hipertensão e hipertensão em comparação com o grupo controle em toda a população (p<0,05 para todos). A análise quantitativa das características indicou níveis séricos de AU (2,92±0,81, 3,06±0,85, 3,22±0,98 mg/d) linearmente aumentados em mulheres normotensas, pré-hipertensas e hipertensas, com um valor de p de 0,008. Os níveis séricos de AU nos quartis correlacionaram-se positivamente com a PAD (p<0,05), principalmente em mulheres. Após o ajuste para idade, sexo, índice de massa corporal (IMC), glicose (GLI), colesterol total (CT), triglicerídeos (TG), colesterol HDL (lipoproteína de alta densidade), as razões de chances ( odds ratios — ORs) e intervalos de confiança (IC) de 95% da pré-hipertensão, dos níveis séricos de AU mais baixos (referentes) aos mais altos foram 1,718 (1,028–2,872), 1,018 (0,627–1,654) e 1,738 (1,003–3,010). Além disso, o segundo quartil dos níveis séricos de AU esteve significativamente associado à hipertensão, com uma OR (IC 95%) de 2,036 (1,256–3,298).

Conclusões

O presente estudo sugere que níveis séricos mais elevados de AU estão positivamente associados à pré-hipertensão e hipertensão entre adultos chineses.

The biology of urate

Urate is the end-product of the purine metabolism in humans. The dominant source of urate is endogenous purines and the remainder comes through diet. Approximately two thirds of urate is eliminated via the kidney with the rest excreted in the feces. While the transporter BCRP, encoded by ABCG2, has been found to play a role in both the gut and kidney, SLC22A12 and SLC2A9 encoding URAT1 and GLUT9, respectively, are the two transporters best characterized. Only 8-12% of the filtered urate is excreted by the kidney. Renal elimination of urate depends substantially on specific transporters, including URAT1, GLUT9 and BCRP. Studies that have assessed the biologic effects of urate have produced highly variable results. Although there is a suggestion that urate may have anti-oxidant properties in some circumstances, the majority of evidence indicates that urate is pro-inflammatory. Hyperuricemia can result in the formation of monosodium urate (MSU) crystals that may be recognized as danger signals by the immune system. This immune response results in the activation of the NLRP3 inflammasome and ultimately in the production and release of interleukin-1β, and IL-18, that mediate both inflammation, pyroptotic cell death, and necroinflammation. It has also been demonstrated that soluble urate mediates effects on the kidney to induce hypertension and can induce long term epigenetic reprogramming in myeloid cells to induce "trained immunity." Together, these sequelae of urate are thought to mediate most of the physiological effects of hyperuricemia and gout, illustrating this biologically active molecule is more than just an "end-product" of purine metabolism.

Uric acid can enhance MAPK pathway-mediated proliferation in rat primary vascular smooth muscle cells via controlling of mitochondria and caspase-dependent cell death

Hyperuricemia may be a risk factor for cardiovascular diseases such as hypertension and atherosclerosis, but the mechanisms underlying uric acid-induced pathological conditions remain unknown. In this study, we investigated the effect of short time and long-term administration of increasing uric acid concentrations on cell viability, proliferative and apoptotic pathways in vascular smooth muscle cells (VSMCs). Cell viability/proliferation was determined with WST-1 assay. Expression levels of mitogen-activated protein kinases (MAPKs) (phosphorylated (p)-p38 and p-p44/42 MAPK), extrinsic (caspase 3, caspase 8), and intrinsic (B-cell lymphoma-extra-large (Bcl-xL)) apoptotic pathway proteins were measured by Western blotting. In order to assess the proliferative effects of uric acid incubations on VSMCs, we monitored the proliferative/apoptosis signaling pathways for up to 24 h. Our results indicated that uric acid increases cell viability at time and dose-dependently in VSMCs. Immunoblotting results showed that uric acid treatment elevated the expression level of p-p38 MAPK but did markedly reduce the protein levels of p-p44/42, compared with all the uric acid doses-treated VSMCs, especially at 1 h. Uric acid stimulation increased caspase-3 protein levels and decreased Bcl-xL, but did not alter caspase-8 protein expression at the same dose and time. Furthermore, low uric acid incubations (0-7.5 mg/dL) did not affect any signaling pathways for long time points (6-24 h). In conclusion, our study demonstrates for the first time that VSMCs induced with uric acid can affect cell viability, proliferative, and apoptosis pathways at the widest time and dose range. These findings provide a better understanding of the uric acid effects related to vascular impairments.

Allopurinol ameliorates high fructose diet induced hepatic steatosis in diabetic rats through modulation of lipid metabolism, inflammation, and ER stress pathway

Excess fructose consumption contributes to development obesity, metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD). Uric acid (UA), a metabolite of fructose metabolism, may have a direct role in development of NAFLD, with unclear mechanism. This study aimed to evaluate role of fructose and UA in NAFLD and explore mechanisms of allopurinol (Allo, a UA lowering medication) on NAFLD in Otsuka Long-Evans Tokushima Fatty (OLETF) rats fed a high fructose diet (HFrD), with Long-Evans Tokushima Otsuka (LETO) rats used as a control. There were six groups: LETO, LETO-Allo, OLETF, OLETF-Allo, OLETF-HFrD, and OLETF-HFrD-Allo. HFrD significantly increased body weight, epididymal fat weight, and serum concentrations of UA, cholesterol, triglyceride, HbA1c, hepatic enzymes, HOMA-IR, fasting insulin, and two hour-glucose after intraperitoneal glucose tolerance tests, as well as NAFLD activity score of liver, compared to the OLETF group. Allopurinol treatment significantly reduced hepatic steatosis, epididymal fat, serum UA, HOMA-IR, hepatic enzyme levels, and cholesterol in the OLETF-HFrD-Allo group. Additionally, allopurinol significantly downregulated expression of lipogenic genes, upregulated lipid oxidation genes, downregulated hepatic pro-inflammatory cytokine genes, and decreased ER-stress induced protein expression, in comparison with the OLETF-HFrD group. In conclusion, allopurinol ameliorates HFrD-induced hepatic steatosis through modulation of hepatic lipid metabolism, inflammation, and ER stress pathway. UA may have a direct role in development of fructose-induced hepatic steatosis, and allopurinol could be a candidate for prevention or treatment of NAFLD.

Serum Uric Acid and Mortality in Patients with Chronic Kidney Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Existing studies suggested conflicting relationships between serum uric acid (SUA) and mortality in CKD patients. The present meta-analysis aimed to determine whether SUA can be a predictor for mortality in CKD cohorts.

METHOD

A systematical search was conducted on PubMed, EMBASE, and The Cochrane Library to identify studies reporting the relationship between SUA level and all-cause and cardiovascular mortality in CKD populations. In addition, random-effects models were adopted to calculate the hazard ratios (HRs) and corresponding 95% confidence intervals (CIs).

RESULTS

On the whole, 29 studies were involved. In the present meta-analysis, patients exhibiting the maximum SUA level showed an association with a significantly higher risk for all-cause mortality (HR, 1.30; 95% CI, 1.06-1.59) compared with patients exhibiting the minimum SUA level. As revealed from the meta-analysis of 8 studies, low level of SUA was another predictor for all-cause mortality in patients with CKD (HR, 1.36; 95% CI, 1.20-1.54). No significant relationship was identified between SUA and cardiovascular mortality.

CONCLUSIONS

Higher and lower SUA levels are both associated with significantly increased risk of all-cause mortality in patients with CKD. A appreciate dose of treatment of lowering SUA agents should be confirmed.

Elevated serum uric acid is associated with a greater inflammatory response and with short- and long-term mortality in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND AND AIMS

Despite elevated serum uric acid (eSUA) has been identified as independent risk factor for cardiovascular diseases, its prognostic value in the setting of ST-segment elevation myocardial infarction (STEMI) is still controversial. Although the mechanisms of this possible relationship are unsettled it has been suggested that eSUA could trigger the inflammatory response. This study sought to investigate the association between eSUA with short- and long-term mortality and with inflammatory response in patients with STEMI treated with primary percutaneous coronary intervention (pPCI).

METHODS AND RESULTS

Blood samples were collected on admission and at 24 and 48 h after pPCI: the inflammatory biomarkers C-reactive protein (CRP), neutrophil count and neutrophil to lymphocytes ratio (NLR) were considered. Baseline eSUA was defined as ≥6.8 mg/dl. Cumulative 30-days and 1-year mortalities were estimated using the Kaplan-Meyer analysis. Multivariable analyses were performed by Cox proportional hazard models. In the 2369 patients with STEMI considered, 30-day mortality was 5.8% among patients with eSUA and 2% among patient with normal SUA level (p < 0.001); 1-year mortality was 8.5% vs 4%, respectively (p < 0.001). At multivariable analyses eSUA was an independent predictor of 30-day mortality (HR 1.196, 95%CI 1.006-1.321, p = 0.042) and 1-year mortality (HR 1.178, 95%CI 1.052-1.320, p = 0.005). eSUA patients presented higher values in on admission CRP (p < 0.001) and in neutrophil count and NLR at 24 h (respectively, p = 0.020 and p < 0.001) and at 48 h (p = 0.018 and p < 0.001) compared to patients with normal SUA levels.

CONCLUSIONS

Elevated serum uric acid is associated with higher short- and long-term mortality and with a greater inflammatory response after reperfusion in patients with STEMI treated with primary PCI.

Prevalence of Hyperuricemia and the Use of Allopurinol in Older Poles-Results from a Population-Based PolSenior Study

BACKGROUND

Our study analyzes the frequency and risk factors of hyperuricemia and the use of allopurinol in a representative cohort of the older Polish adult population.

METHODS

The analysis was a part of a cross-sectional PolSenior study on aging in Poland. The complete medication data were available in 4873 out of 4979 community dwelling respondents aged 65 and over. Serum uric acid concentrations were evaluated in 4028 participants (80.9% of the cohort).

RESULTS

Hyperuricemia was observed in 28.2% of women and 24.7% of men. Ten risk factors of hyperuricemia were selected based on multivariable LASSO logistic regression analysis. Nine factors showed significant odds ratios: eGFR < 60 mL/min/1.73 m2 (OR = 4.10), hypertriglyceridemia (OR = 1.88), obesity (OR = 1.75), heart failure (1.70), CRP > 3.0 mg/dL (OR = 1.64), coronary artery disease (OR = 1.30), use of loop-diuretics (OR = 4.20), hydrochlorothiazide (OR = 2.96), and thiazide-like diuretics (OR = 2.81). Allopurinol was used by 2.8% of men and 1.8% of women. The therapy was considered effective in 46.7% of men and 53.3% of women.

CONCLUSIONS

Hyperuricemia was present in 23.1% (95% CI: 21.8-24.4) of the older Polish population. The frequency of hyperuricemia increases with age, reaching 30.5% in men and 33.7% in women aged 90 years or more. Chronic kidney disease, obesity, heart failure, hypertriglyceridemia, and the use of diuretics were the strongest risk factors for hyperuricemia in older adults. The treatment with allopurinol was ineffective in more than half of participants.