Uric acid in chronic heart failure: a marker of chronic inflammation

Low Serum Uric Acid Levels are Associated with Severe Diabetic Foot Infection: A Cross-Sectional Study from China

Diabetic foot ulcers (DFUs) are among the most serious complications of diabetes which are associated with high disability and mortality rates. This study aims to investigate the associations between uric acid (UA) levels and diabetic foot ulcer (DFU) characteristics. In total, 1820 participants with DFUs were included in this study; 192 and 1628 participants were included in the hyperuricemia group (HUA, UA > 420 µmol/L) and the nonhyperuricemia group (NHUA, UA ≤420 µmol/L), respectively. The NHUA group was divided into a middle-UA subgroup (SMUA, 420 µmol/L ≥ UA ≥ 180 µmol/L; 304 individuals) and a low-UA subgroup (SLUA, UA <180 µmol/L; 1324 individuals). There were no significant differences in the rates of deep ulcers, severe infection or amputation between NHUA and HUA. In univariate analysis of subgroups, the differences in the rates of deep ulcers, severe infection and amputation were significant. After adjusting for confounders (sex, fasting glucose level, diabetes duration, eGFR, deep ulcers and severe infection) in multivariate analysis, the severe infection rate (OR = 4.0, 95%CI 1.6-10.0, P < 0.01) was still significantly greater in the SLUA group than in the SMUA group while the rate of deep ulcers (OR =2.4, 95%CI 1.0-6.1, P = 0.06) and amputation (OR =1.1, 95%CI 0.3-4.3, P = 0.91) showed non-statistical difference. UA levels below 180 µmol/L can be a risk factor for severe infection in DFUs.

Whole exome sequence reveals genetic profiles of primary cardiomyopathy and genotype-phenotype association in Chinese population

BACKGROUND

Primary cardiomyopathies are major causes of heart failure, placing a substantial burden on both individuals and society. Revealing its genetic profiles can lead to a better understanding of the mechanism and is critical for disease prevention and treatment.

METHOD

Primary cardiomyopathy patients were enrolled and whole exome sequence was conducted to analyze their genetic profiles. Retrospective clinical information extraction and analysis of sequence data were implemented.

RESULTS

A total of 77 primary cardiomyopathy patients were enrolled, comprising 65 patients with dilated cardiomyopathy (DCM) and 12 with hypertrophic cardiomyopathy (HCM). Among the DCM patients, 13 variants classified as pathogenic (P) or likely pathogenic (LP) were identified in 12 patients (18.46%), predominantly in genes associated with the nuclear envelope and sarcomere. Among HCM patients, 6 P/LP variants were discovered in 6 (50%) patients. Taking variants of uncertain significance (VUS) into consideration, an analysis of the association between the number of variants carried by patients and their clinical characteristics revealed that DCM patients with more than one variant had a higher proportion of hyperuricemia.

CONCLUSIONS

We map a comprehensive profile of primary cardiomyopathy in Chinese population and, for the first time, identify a possible association between hyperuricemia and the number of genetic variants carried by DCM patients.

Association between magnesium depletion score and prevalence of hyperuricemia in American adults: a study based on NHANES 2007-2018

Background

The Magnesium Depletion Score (MDS) is a novel indicator that integrates multiple factors to assess systemic magnesium depletion. However, its association with hyperuricemia (HUA) prevalence remains unclear. This study aims to investigate the relationship between MDS and the prevalence of HUA.

Methods

A cross-sectional analysis was conducted using data from the 2007-2018 National Health and Nutrition Examination Survey (NHANES). The MDS was derived by integrating multiple risk factors associated with magnesium depletion: the use of diuretics and proton pump inhibitors (PPI), estimated glomerular filtration rate (eGFR), and alcohol consumption exceeding recommended thresholds. Univariable and multivariable logistic regression models assessed the association between MDS and HUA. Subgroup and sensitivity analyses, including the exclusion of gout patients, further evaluated this association.

Results

Among 18,761 participants, higher MDS were associated with an increased prevalence of HUA. Multivariable logistic regression confirmed a significant positive association between MDS and HUA (OR = 1.73, 95% CI = 1.62-1.84). Restricted cubic splines (RCS) further characterized the non-linear relationship between MDS and HUA prevalence. Subgroup analysis indicated a positive association between MDS and HUA, with significant interactions observed for sex and body mass index. Sensitivity and additional analyses reinforced the robustness of these findings.

Conclusion

Among U.S. adults, higher MDS were significantly associated with an increased prevalence of HUA, suggesting that interventions targeting magnesium deficiency could be beneficial in reducing HUA prevalence within this population. However, prospective studies are needed to further confirm these findings.

Hyperuricaemia elevates risk of short-term readmission and mortality in patients with heart failure

BACKGROUND

Heart failure (HF) is a leading cause of morbidity and mortality worldwide. Serum uric acid (SUA), a product of purine metabolism, has been implicated in HF progression. However, the association between hyperuricaemia and the short-term readmission and mortality in patients with HF remains controversial.

METHODS

In this retrospective cohort study, we analysed data from a HF database specific to the Chinese population. The primary endpoint was short-term readmission or all-cause mortality within 90 days. Participants with HF were categorised into normouricaemia group (NUA) and hyperuricaemia group (HUA) based on a SUA threshold of 420 µmol/L. The association between SUA and primary endpoint was evaluated using Kaplan-Meier survival curves and Cox regression analysis.

RESULTS

Baseline characteristics revealed significant differences between NUA and HUA groups, with the latter exhibiting a higher prevalence of males, chronic kidney disease (CKD) and elevated levels of various biomarkers. During a 90-day follow-up, 493 (26.6%) participants reached the primary endpoint, with a higher incidence observed in the HUA group at 31.2%, compared with 20.1% in the NUA group. When a threshold effect was identified at 420 µmol/L, a non-linear association was observed between SUA and the primary endpoint. After adjusting for gender, age, New York Heart Association class, CKD, systolic blood pressure (SBP) and potassium, the HUA group exhibited a higher risk for the primary endpoint compared with the NUA group (HR: 1.40, 95% CI: 1.14 to 1.72, p=0.001). Additionally, the risk increased across quartiles of SUA (P for trend=0.002). Furthermore, stratified analyses indicated a stronger association in patients without CKD (P interaction=0.033).

CONCLUSION

Hyperuricaemia is independently associated with an increased risk of short-term readmission and mortality in patients with HF. Our findings suggest that monitoring and managing SUA could be crucial in improving patient with HF outcomes.

Association of uric acid with body adiposity and biochemical parameters in kidney transplant patients

BACKGROUND

Obesity and various biochemical parameters, including triglycerides, cholesterol, glucose, C-reactive protein, and estimated glomerular filtration rate, have been linked to elevated uric acid (UA) levels in populations with normal kidney function due to decreased UA excretion and/or increased UA synthesis. However, it remains unclear whether all these factors exhibit similar associations with UA levels in clinical populations characterized by compromised renal function, such as kidney transplant patients (KTPs).

OBJECTIVE

To evaluate whether serum UA levels are associated with body adiposity and biochemical parameters in KTPs.

METHODS

A cross-sectional study involving 113 KTPs was conducted. Body fat was estimated using bioelectrical impedance, and waist circumference was measured using an inelastic tape. Serum levels of UA, creatinine, glucose, triglycerides, total cholesterol, and its fractions were measured using the colorimetric method. C-reactive protein levels were assessed using the immunoturbidimetric method, and urea levels were determined via enzymatic kinetics. Glomerular filtration rate was estimated using the chronic kidney disease epidemiology collaboration equation. Linear regression analyses were employed to assess the association between serum UA levels and body adiposity as well as biochemical parameters, while adjusting for confounders.

RESULTS

Serum UA levels exhibited a positive association with creatinine (β = 0.402; p = 0.013) and urea (β = 0.024; p = 0.001), while demonstrating an inverse association with estimated glomerular filtration rate (β = -0.030; p < 0.001). However, serum UA levels were not significantly associated with fat mass (both in kilograms and as a percentage), waist circumference, triglycerides, C-reactive protein, glucose, HDL cholesterol, LDL cholesterol, VLDL cholesterol, or total cholesterol.

CONCLUSION

Serum UA levels are only associated with biochemical parameters linked to renal function in KTPs. Consequently, in individuals with suboptimal renal function, such as KTPs, UA does not exhibit associations with other biochemical parameters and body adiposity, as commonly observed in non-renal disease populations.

Is cardiac function associated with the clinical course of disease in patients with gout? A prospective study

OBJECTIVE

To analyze the function of the left heart in patients with different courses of gout, the independent influencing factors for left heart functional changes, and interactions between left atrial and left ventricular functions.

METHODS

Patients with gout (n = 171) were selected; 87 patients with a disease course <10 years were included in Group I, and 84 patients with a disease course ≥10 years were included in Group II. Ninety-four healthy volunteers comprised the control group.

RESULTS

The intergroup differences in cardiac strain parameters were statistically significant (p < .05). Moreover, the differences gradually declined with disease progression. Multivariate logistic regression analysis showed that uric acid was an independent predictor of decreased left ventricular global longitudinal strain (LVGLS). Moreover, LVGLS had a positive effect on the left atrial systolic rate (LASr) and the left atrial systolic contraction time (LASct) but no interaction with the left atrial systolic contraction duration (LAScd).

CONCLUSION

The course of the disease significantly affected the function of the left heart in gout patients, and uric acid was observed to be an independent predictor of decreased LVGLS in gout patients.

Impacts of Febuxostat on Cerebral and Cardiovascular Events in Elderly Patients with Hyperuricemia: Post Hoc Analysis of a Randomized Controlled Trial

A recent meta-analysis found no benefit of uric acid-lowering therapy including febuxostat on death, cardiovascular events, or renal impairment. However, there may be populations that benefit from febuxostat in reducing mortality and cerebral and cardiovascular events. The aim of the present study was to examine the clinical benefit of febuxostat in elderly patients stratified by age using Febuxostat for Cerebral and CaRdiorenovascular Events PrEvEntion StuDy (FREED) data. FREED was a randomized study involving patients aged 65 years or older with hyperuricemia and risk factors for cerebral, cardiovascular, or renal diseases. A total of 1,070 patients were included in this post hoc analysis, divided into 2 age groups: 65-74 years and ≥ 75 years. Patients were randomized into febuxostat and non-febuxostat groups, with uric acid levels monitored for 36 months. The primary composite end point included cerebral, cardiovascular, and renal events. In patients aged between 65 and 74 years, febuxostat significantly reduced the risk of future cerebral and cardiorenovascular events. However, no effects of febuxostat were found in the older population aged ≥ 75 years. Heterogeneity in potential interactions between the age and febuxostat treatment was particularly observed in non-fatal cerebral and cardiovascular events and all-cause death. Patients aged ≥ 75 years exhibited more pre-existing factors associated with cerebral and cardiorenovascular events than those aged 65-74 years. The effectiveness of febuxostat varies by age group, with potential benefits for patients aged 65-74 years. The effects of febuxostat are complex and it is important to consider patient characteristics in its clinical use.

Gender differences in the relationship between serum uric acid and the long-term prognosis in heart failure: a nationwide study

BACKGROUND

Serum uric acid (SUA) is an important pathogenetic and prognostic factor for heart failure (HF). Gender differences are apparent in HF. Furthermore, gender differences also exist in the association between SUA and prognosis in various cardiovascular diseases. However, the gender difference for SUA in the prediction of long-term prognosis in HF is still ambiguous.

METHODS

A total of 1593 HF patients (897 men, 696 women) from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 cycle were enrolled in our final analysis. Participants were categorized according to gender-specific SUA tertile. We assessed the association between SUA and long-term prognosis of HF patients, defined as all-cause mortality and cardiovascular mortality, in different genders via Kaplan-Meier curve analysis, Cox proportional hazard model, and Fine-Gray competing risk model. The restricted cubic spline (RCS) was performed to investigate the dose-response relationship between SUA and outcomes.

RESULTS

Gender differences exist in demographic characteristics, clinical parameters, laboratory tests, and medication of HF patients. After a median follow-up of 127 months (95% CI 120-134 months), there were 853 all-cause deaths (493 events in men, 360 events in women) and 361 cardiovascular deaths (206 events in men, 155 events in women). Kaplan-Meier analysis showed that SUA had gender difference in the prediction of cardiovascular mortality (Log-rank p < 0.001, for male, Log-rank p = 0.150, for female), but not in all-cause mortality. Multivariate Cox regression analysis revealed that elevated SUA levels were associated with higher all-cause mortality and cardiovascular mortality in men (HR 1.11, 95% CI 1.05-1.18, p < 0.001, for all-cause death; HR 1.18, 95% CI 1.09-1.28, p < 0.001, for cardiovascular death), but not in women (HR 1.05, 95% CI 0.98-1.12, p = 0.186, for all-cause death; HR 1.01, 95% CI 0.91-1.12, p = 0.902, for cardiovascular death). Even using non-cardiovascular death as a competitive risk, adjusted Fine-Gray model also illustrated that SUA was an independent predictor of cardiovascular death in men (SHR 1.17, 95% CI 1.08-1.27, p < 0.001), but not in women (SHR 0.98, 95% CI 0.87 - 1.10, p = 0.690).

CONCLUSIONS

Gender differences in the association between SUA and long-term prognosis of HF existed. SUA was an independent prognostic predictor for long-term outcomes of HF in men, but not in women.

Relationship of Serum Uric Acid with Kidney Function Decline Mediated by Systemic Arterial Stiffness: A Retrospective Cohort Study in Japan

Hyperuricemia is associated with kidney function decline (KFD), although whether hyperuricemia directly causes nephrotoxicity or is indirectly mediated by systemic arterial stiffening remains unclear. We examined the detailed relationship of serum uric acid (SUA) with KFD and potential mediation by arterial stiffness. Study population was 27,648 urban residents with an estimated glomerular filtration rate (eGFR) of ≥60 mL/min/1.73 m2 at baseline, and they participated in a median of three consecutive annual health examinations. Arterial stiffness was assessed using cardio-ankle vascular index (CAVI). KFD was defined as a decrease in eGFR to below 60. Multivariate analysis showed an association between baseline SUA and CAVI independent of eGFR. During the study period, 6.6% of participants developed KFD. Stratified analysis revealed a linear relationship between the contribution of CAVI or SUA and KFD. ROC analysis determined a cutoff CAVI of 8.0 (males) or 7.9 (females) and a cutoff SUA of 6.3 (males) or 4.5 mg/dL (females) for predicting KFD. The linkage between SUA and CAVI was associated with a greater increase in the hazard ratio for KFD with an increase in SUA. CAVI showed the mediating effect on the relationship of SUA with KFD after an adjustment for confounders. SUA was associated positively with CAVI-mediated KFD. Further studies should verify whether intensive SUA-lowering treatment prevents KFD via improving vascular function.

Associations of long-term mortality with serum uric acid at admission in acute decompensated heart failure with different phenotypes

BACKGROUND AND AIMS

It remains unclear whether the long-term prognostic value of serum uric acid (SUA) at admission differs in acute decompensated heart failure (HF) patients across the spectrum of left ventricular ejection fraction (EF).

METHODS AND RESULTS

In 2375 patients (38.9% women; mean age, 68.8 years), we assessed the risk of long-term (>1 year) all-cause mortality associated with per 1-SD increase in SUA at admission, using multivariable Cox regression in HF with preserved (HFpEF), mildly reduced (HFmrEF) and reduced (HFrEF) EF. During a median follow-up of 4.1 years, the long-term mortality rate was 39.9%. In all patients, the multivariable-adjusted hazard ratio (HR) expressing the risk of long-term mortality associated with SUA was 1.18 (95% CI, 1.11-1.26; P < 0.001). Compared with the low tertile of the SUA distribution, the sex- and age-adjusted cumulative incidence of long-term mortality was higher in the top tertile. In patients with HFpEF and HFrEF, SUA predicted the risk of long-term mortality with HRs amounting to 1.12 (95% CI, 1.02-1.21; P = 0.012) and 1.28 (95% CI, 1.12-1.47; P < 0.001), respectively. However, there were no associations between the risk of mortality and SUA in HFmrEF. Furthermore, age, sex, NYHA class, and the prevalence of coronary heart disease interacted significantly with SUA for predicting long-term mortality.

CONCLUSION

Higher levels of SUA at admission were associated with higher risk of long-term mortality in patients with different HF subtypes. The risk conferred by SUA was age and sex dependent. Our observations highlight that measuring SUA at admission may help to improve risk stratification.

Assessment of Cardiovascular Disease Among Predominantly Black Gout Patients

INTRODUCTION

Although the association between gout and cardiovascular disease (CVD) has been extensively studied, scarce data are available for the Black population. We aimed to assess the association between gout and CVD in a predominantly Black urban population with gout.

METHODS

A cross-sectional analysis was performed between a gout cohort and an age-/sex-matched control group. Clinical parameters and 2D echocardiograms were reviewed for the patients with gout and heart failure (HF). The primary outcome studied includes the prevalence and strength of association between gout and CVD. Secondary outcomes studied includes strength of association of gout and HF categorized by ejection fraction, mortality, and HF readmissions.

RESULTS

Four hundred seventy-one patients with gout had a mean age of 63.7 ± 0.5 years; 89% were Black, 63% were men, and mean body mass index was 31.3 ± 0.4 kg/m 2 . Hypertension, diabetes mellitus, and dyslipidemia were present in 89%, 46%, and 52%, respectively. Compared with controls, patients with gout had significantly higher rates of angina, arrhythmia, coronary artery disease/stents, myocardial infarction, coronary artery bypass graft surgery, cerebrovascular accident, and peripheral vascular disease. The adjusted odds ratio for CVD was 2.9 (95% confidence interval, 1.9-4.5; p < 0.001). Gout patients had a higher prevalence of HF with 45% (n = 212) compared with controls with 9.4% (n = 44). Adjusted odds ratio for HF risk was 7.1 (95% confidence interval, 4.7-10.6; p < 0.01).

CONCLUSIONS

Gout in a predominantly Black population confers 3 times the CVD risk and 7 times HF-specific risk compared with age- and sex-matched cohort. Further research is needed to confirm our findings and to develop interventions to reduce morbidity associated with gout.

High- versus low-dose losartan and uric acid: An analysis from HEAAL

BACKGROUND

Serum uric acid (SUA) is activated in catabolic, hypoxic, and inflammatory conditions characteristic of heart failure (HF) and is a source of reactive oxygen species. Losartan is unique among other angiotensin receptor blockers in reducing SUA.

OBJECTIVES

To study the patient characteristics and outcome associations by SUA levels, as well as the effect of high- vs. low-dose losartan on SUA levels in HF.

METHODS

HEAAL was a double-blind trial, comparing the effect of two doses of losartan 150 (high dose) vs. 50 (low dose) mg/day among 3834 patients with symptomatic HF, a left ventricular ejection fraction≤40 %, and known intolerance to angiotensin-converting enzyme inhibitors. In the present study, we studied the associations of SUA with outcomes and the effect of high- vs. low-dose losartan on SUA levels, incident hyperuricemia, and gout.

RESULTS

Patients with higher SUA had more comorbidities, worse renal function, were more symptomatic, used diuretics more frequently, and were 1.5- to 2-fold more likely to experience HF hospitalizations and cardiovascular death. The benefit of high-dose losartan to improve HF outcomes was not influenced by baseline SUA levels (interaction p > 0.1). Compared with low-dose, high-dose losartan reduced SUA by -0.27 (-0.34 to -0.21) mg/dL, p < 0.001. The incidence of hyperuricemia was reduced with high-dose losartan, but the incidence of gout was not.

CONCLUSIONS

In HEAAL, hyperuricemia was associated with worse outcomes. High-dose losartan reduced SUA and hyperuricemia more than low-dose and the cardiovascular benefits of high-dose losartan were not modified by SUA levels.

Novel Reversible Inhibitors of Xanthine Oxidase Targeting the Active Site of the Enzyme

Xanthine oxidase (XO) is a flavoprotein catalysing the oxidation of hypoxanthine to xanthine and then to uric acid, while simultaneously producing reactive oxygen species. Altered functions of XO may lead to severe pathological diseases, including gout-causing hyperuricemia and oxidative damage of tissues. These findings prompted research studies aimed at targeting the activity of this crucial enzyme. During the course of a virtual screening study aimed at the discovery of novel inhibitors targeting another oxidoreductase, superoxide dismutase, we identified four compounds with non-purine-like structures, namely ALS-1, -8, -15 and -28, that were capable of causing direct inhibition of XO. The kinetic studies of their inhibition mechanism allowed a definition of these compounds as competitive inhibitors of XO. The most potent molecule was ALS-28 (Ki 2.7 ± 1.5 µM), followed by ALS-8 (Ki 4.5 ± 1.5 µM) and by the less potent ALS-15 (Ki 23 ± 9 µM) and ALS-1 (Ki 41 ± 14 µM). Docking studies shed light on the molecular basis of the inhibitory activity of ALS-28, which hinders the enzyme cavity channel for substrate entry consistently with the competitive mechanism observed in kinetic studies. Moreover, the structural features emerging from the docked poses of ALS-8, -15 and -1 may explain the lower inhibition power with respect to ALS-28. All these structurally unrelated compounds represent valuable candidates for further elaboration into promising lead compounds.

Research Progress on the Relationship between Dietary Patterns and Hyperuricemia

As the final metabolite of purine metabolism, uric acid is critically associated with human health. The serum uric acid level is regulated by diet and the metabolic capacity of the human body. The impaired control of uric acid metabolism and excretion is associated with the increased level of serum uric acid, which ultimately results in hyperuricemia. Hyperuricemia is the "fourth-highest" after hypertension, hyperglycemia, and hyperlipidemia. With progress made in the relationship between diet and hyperuricemia, different dietary patterns and lifestyles have been discussed, such as exercise, the amount intake of meat, seafood, supplements with omega-3 fatty acids, sugar-sweetened soft drinks and energy drinks, and lower-fat-containing foods as well as drinking beer, wine, and spirits in the present article. This study demonstrated that a lower risk of hyperuricemia is substantially correlated with higher baseline adherence to MeDiet, and plant polyphenols can combat hyperuricemia by blocking xanthine oxidase.

Uric Acid Predicts Recovery of Left Ventricular Function and Adverse Events in Heart Failure With Reduced Ejection Fraction: Potential Mechanistic Insight From Network Analyses

Background and Aims

Heart failure with reduced ejection fraction (HFrEF) still carries a high risk for a sustained decrease in left ventricular ejection fraction (LVEF) even with the optimal medical therapy. Currently, there is no effective tool to stratify these patients according to their recovery potential. We tested the hypothesis that uric acid (UA) could predict recovery of LVEF and prognosis of HFrEF patients and attempted to explore mechanistic relationship between hyperuricemia and HFrEF.

Methods

HFrEF patients with hyperuricemia were selected from the National Inpatient Sample (NIS) 2016–2018 database and our Xianyang prospective cohort study. Demographics, cardiac risk factors, and cardiovascular events were identified. Network-based analysis was utilized to examine the relationship between recovery of LVEF and hyperuricemia, and we further elucidated the underlying mechanisms for the impact of hyperuricemia on HFrEF.

Results

After adjusting confounding factors by propensity score matching, hyperuricemia was a determinant of HFrEF [OR 1.247 (1.172–1.328); P < 0.001] of NIS dataset. In Xianyang prospective cohort study, hyperuricemia is a significant and independent risk factor for all-cause death (adjusted HR 2.387, 95% CI 1.141–4.993; P = 0.021), heart failure readmission (adjusted HR 1.848, 95% CI 1.048–3.259; P = 0.034), and composite events (adjusted HR 1.706, 95% CI 1.001–2.906; P = 0.049) in HFrEF patients. UA value at baseline was negatively correlated to LVEF of follow-ups (r = −0.19; P = 0.046). Cutoff UA value of 312.5 μmmol/L at baseline can work as a predictor of LVEF recovery during follow-up, with the sensitivity of 66.7%, the specificity of 35.1%, and the accuracy of 0.668 (95% CI, 0.561–0.775; P = 0.006). Moreover, gene overlap analysis and network proximity analysis demonstrated a strong correlation between HFrEF and Hyperuricemia.

Conclusion

Lower baseline UA value predicted the LVEF recovery and less long-term adverse events in HFrEF patients. Our results provide new insights into underlying mechanistic relationship between hyperuricemia and HFrEF.

Uric acid and sodium-glucose cotransporter-2 inhibition with empagliflozin in heart failure with reduced ejection fraction: the EMPEROR-reduced trial

Background

The sodium-glucose cotransporter-2 inhibitor empagliflozin decreases the risk of cardiovascular death or hospitalization for heart failure (HF) in patients with HF with reduced ejection fraction. Empagliflozin reduces serum uric acid (SUA), but the relevance of this effect in patients with HF is unclear. This study aimed to investigate the effect of empagliflozin on SUA levels and the therapeutic efficacy of empagliflozin in relation to SUA.

Methods

The association between SUA and the composite primary outcome of cardiovascular death or hospitalization for worsening HF, its components, and all-cause mortality was investigated in 3676 patients of the EMPEROR-Reduced trial (98.6% of the study cohort). The treatment effect of empagliflozin was studied in relation to SUA as continuous variable, to clinical hyperuricaemia (SUA >5.7 mg/dL for women, >7.0 mg/dL for men) and in subgroups of patients of tertiles of SUA.

Results

Hyperuricaemia was prevalent in 53% of patients with no sex differences. Elevated SUA (highest tertile, mean SUA 9.38 ± 1.49 mg/dL) was associated with advanced severity of HF and with worst outcome [composite outcome, hazard ratio (HR) 1.64 (95% confidence interval, CI 1.28–2.10); cardiovascular mortality, HR 1.98 (95% CI 1.35–2.91); all-cause mortality, HR 1.8 (95% CI 1.29–2.49), all P < 0.001] in multivariate adjusted analyses, as compared with the lowest tertile. SUA was reduced following treatment with empagliflozin at 4 weeks (vs. placebo: −1.12 ± 0.04 mg/dL, P < 0.0001) and remained lower throughout follow-up, with a similar reduction in all prespecified subgroups. Empagliflozin reduced events of clinically relevant hyperuricaemia (acute gout, gouty arthritis or initiation of anti-gout therapy) by 32% [HR 0.68 (95% CI 0.52–0.89), P = 0.004]. The beneficial effect of empagliflozin on the primary endpoint was independent of baseline SUA [HR 0.76 (95% CI 0.65–0.88), P < 0.001) and of the change in SUA at 4 weeks [HR 0.81 (95% CI 0.69–0.95), P = 0.012]. As a hypothesis-generating finding, an interaction between SUA and treatment effect suggested a benefit of empagliflozin on mortality (cardiovascular and all-cause mortality) in patients in elevated SUA (P for interaction = 0.005 and = 0.011, respectively).

Conclusion

Hyperuricaemia is common in HF and is an independent predictor of advanced disease severity and increased mortality. Empagliflozin induced a rapid and sustained reduction of SUA levels and of clinical events related to hyperuricaemia. The benefit of empagliflozin on the primary outcome was observed independently of SUA.

Association of serum uric acid with biventricular myocardial dysfunction in patients with type 2 diabetes mellitus

BACKGROUND AND AIMS

Increased serum uric acid (SUA) is common in type 2 diabetes mellitus (T2DM) and is associated with left ventricular (LV) myocardial dysfunction. Nonetheless the association of SUA with right ventricular (RV) function in T2DM has not been studied. This study aimed to investigate the association of SUA with biventricular myocardial function in patients with T2DM.

METHODS AND RESULTS

A total of 560 patients with T2DM were enrolled and divided into four groups according to sex-specific quartiles of SUA. Transthoracic echocardiography was performed and two-dimensional speckle tracking was used to measure biventricular myocardial strain, including LV global longitudinal strain (GLS), circumferential strain (CS), radial strain (RS), and RV free wall longitudinal strain (RV-FWLS). The absolute value of all biventricular strain parameters showed a stepwise decrease across SUA quartiles (all P < 0.01). In particular, LV assessment by GLS, CS and RS demonstrated that those in the 4th quartile were impaired compared with the other quartiles (all P < 0.05). Similarly, RV-FWLS of the 4th quartile was significantly impaired compared with the 1st and 2nd quartiles (all P < 0.05). The same reduction in biventricular strain across SUA quartiles was observed in patients with estimated glomerular filtration rate < or ≥60 ml/min/1.73 m², and glycated hemoglobin < or ≥7.0% (all P < 0.05). Multivariable linear regression analysis demonstrated that higher quartile of SUA was independently associated with impaired biventricular myocardial strain (all P < 0.05).

CONCLUSIONS

SUA was independently associated with biventricular myocardial dysfunction in asymptomatic T2DM patients, regardless of renal function or diabetic control.

Subclinical Heart Dysfunction in Relation to Metabolic and Inflammatory Markers: A Community-Based Study

BACKGROUND

Population studies investigating the contribution of immunometabolic disturbances to heart dysfunction remain scarce. We combined high-throughput biomarker profiling, multidimensional network analyses, and regression statistics to identify immunometabolic markers associated with subclinical heart dysfunction in the community.

METHODS

In 1,236 individuals (mean age, 51.0 years; 51.5% women), we measured 39 immunometabolic markers and assessed echocardiographic indexes of left ventricular diastolic dysfunction (LVDD) and left atrial (LA) reservoir dysfunction. We used partial least squares (PLS) to filter the most relevant biomarkers related to the echocardiographic characteristics. Subsequently, we assessed the associations between the echocardiographic features and biomarkers selected in PLS while accounting for clinical confounders.

RESULTS

Influential biomarkers in PLS of echocardiographic characteristics included blood sugar, γ-glutamyl transferase, d-dimer, ferritin, hemoglobin, interleukin (IL)-4, IL-6, and serum insulin and uric acid. In stepwise regression incorporating clinical confounders, higher d-dimer was independently associated with higher E/e' ratio and LA volume index (P ≤ 0.05 for all). In multivariable-adjusted analyses, the risk for LVDD increased with higher blood sugar and d-dimer (P ≤ 0.048). After full adjustment, higher serum insulin and serum uric acid were independently related to worse LA reservoir strain and higher risk for LA reservoir dysfunction (P ≤ 0.039 for all). The biomarker panels detected LVDD and LA reservoir dysfunction with 87% and 79% accuracy, respectively (P < 0.0001).

CONCLUSIONS

Biomarkers of insulin resistance, hyperuricemia, and chronic low-grade inflammation were associated with cardiac dysfunction. These biomarkers might help to unravel cardiac pathology and improve the detection and management of cardiac dysfunction in clinical practice.

Decreased Platelet Inhibition by Thienopyridines in Hyperuricemia

PURPOSE

Hyperuricemia carries an increased risk of atherothrombotic events in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). This may at least in part be due to inadequate P2Y12 inhibition. The aim of this study was to prospectively investigate the potential association between hyperuricemia and decreased platelet inhibition by P2Y12 antagonists.

METHODS

Levels of uric acid as well as on-treatment residual platelet reactivity in response to adenosine diphosphate (ADP) were assessed in 301 clopidogrel-treated patients undergoing elective angioplasty and stenting, and in 206 prasugrel- (n = 118) or ticagrelor-treated (n = 88) ACS patients following acute PCI. Cut-off values for high on-treatment residual ADP-inducible platelet reactivity (HRPR) were based on previous studies showing an association of test results with clinical outcomes.

RESULTS

Hyperuricemia was significantly associated with increased on-treatment residual ADP-inducible platelet reactivity in clopidogrel- and prasugrel-treated patients in univariate analyses and after adjustment for differences in patient characteristics by multivariate regression analyses. In contrast, ticagrelor-treated patients without and with hyperuricemia showed similar levels of on-treatment residual platelet reactivity to ADP. HRPR occurred more frequently in clopidogrel- and prasugrel-treated patients with hyperuricemia than in those with normal uric acid levels. In contrast, hyperuricemic patients receiving ticagrelor did not have a higher risk of HRPR compared with those with normal uric acid levels.

CONCLUSION

Hyperuricemia is associated with decreased platelet inhibition by thienopyridines but a normal response to ticagrelor. It remains to be established if lowering uric acid increases the antiplatelet effects of clopidogrel and prasugrel in hyperuricemic patients with HRPR.

Cardiovascular risk in inflammatory arthritis: rheumatoid arthritis and gout

The increased risk of cardiovascular morbidity and mortality in rheumatoid arthritis and gout has been increasingly acknowledged in past decades, with accumulating evidence that gout, just as with rheumatoid arthritis, is an independent cardiovascular risk factor. Although both diseases have a completely different pathogenesis, the underlying pathophysiological mechanisms in systemic inflammation overlap to some extent. Following the recognition that systemic inflammation has an important causative role in cardiovascular disease, anti-inflammatory therapy in both conditions and urate-lowering therapies in gout are expected to lower the cardiovascular burden of patients. Unfortunately, much of the existing data showing that urate-lowering therapy has consistent beneficial effects on cardiovascular outcomes in patients with gout are of low quality and contradictory. We will discuss the latest evidence in this respect. Cardiovascular disease risk management for patients with rheumatoid arthritis and gout is essential. Clinical guidelines and implementation of cardiovascular risk management in daily clinical practice, as well as unmet needs and areas for further investigation, will be discussed.

Role of comorbidities in heart failure prognosis Part 2: Chronic kidney disease, elevated serum uric acid

Despite improvements in pharmacotherapy, morbidity and mortality rates in community-based populations with chronic heart failure still remain high. The increase in medical complexity among patients with heart failure may be reflected by an increase in concomitant non-cardiovascular comorbidities, which are recognized as independent prognostic factors in this population. Heart failure and chronic kidney disease share many risk factors, and often coexist. The presence of kidney failure is associated with incremented risk of cardiovascular and non-cardiovascular mortality in heart failure patients. Chronic kidney disease is also linked with underutilization of evidence-based heart failure therapy that may reduce morbidity and mortality. More targeted therapies would be important to improve the prognosis of patients with these diseases. In recent years, serum uric acid as a determinant of cardiovascular risk has gained interest. Epidemiological, experimental and clinical data show that patients with hyperuricaemia are at increased risk of cardiac, renal and vascular damage and cardiovascular events. Moreover, elevated serum uric acid predicts worse outcome in both acute and chronic heart failure. While studies have raised the possibility of preventing heart failure through the use of uric acid lowering agents, the literature is still inconclusive on whether the reduction in uric acid will result in a measurable clinical benefit. Available evidences suggest that chronic kidney disease and elevated uric acid could worsen heart failure patients' prognosis. The aim of this review is to analyse a possible utilization of these comorbidities in risk stratification and as a therapeutic target to get a prognostic improvement in heart failure patients.

Serum high-density lipoprotein cholesterol serves as a prognostic marker for light-chain cardiac amyloidosis

BACKGROUND

Oxidative stress and inflammation are central in the pathophysiology of light-chain amyloid cardiomyopathy (AL-CM). High-density lipoprotein cholesterol (HDLC) is an antioxidant and acts as an anti-inflammatory regulator. In this study, the prognostic value of serum HDL-C was explored in AL-CM.

METHOD

In this prospective single-center study, two hundred consecutive patients with biopsy-confirmed light-chain amyloidosis (AL) and cardiac involvement were enrolled. Patients were classified into low or normal serum HDL-C groups (HDL-C < 40 mg/dL and HDL-C ≥ 40 mg/dL, respectively). Univariate and multivariate Cox models were used to identify predictors of survival. Kaplan-Meier analysis was performed to compare survival between patients with low or normal serum HDL-C.

RESULTS

Patients with low serum HDL-C were more likely to present with higher levels of cardiac troponin-T (123.4 ng/L vs. 79.1 ng/L, p = 0.026) and higher levels of N-terminal pro-B-type natriuretic peptide (9146 pg/mL vs. 4945 pg/mL, p = 0.011). Patients were followed for a median follow-up period of 19 months, in which 118 (59%) patients died. The median overall survival times for patients with low or normal serum HDL-C were 7 and 16 months, respectively (p = 0.002). Multivariate analysis demonstrated that serum HDL-C (HR 0.984, 95% CI 0.973-0.994, p = 0.003) was independently associated with prognosis, after adjusting for nephrotic syndrome, hepatic involvement, nutritional state, renal function, SBP, DBP, serum uric acid, total cholesterol, Mayo AL 2004 stage, and treatment with chemotherapy.

CONCLUSIONS

HDL-C is a novel serum biomarker for disease severity and prognosis in light-chain cardiac amyloidosis.

Uric Acid Is a Biomarker of Oxidative Stress in the Failing Heart: Lessons Learned from Trials With Allopurinol and SGLT2 Inhibitors

Hyperuricemia increases the risk of heart failure, and higher levels of serum uric acid are seen in patients who have worse ventricular function, functional capacity, and prognosis. Heart failure is also accompanied by an upregulation of xanthine oxidase, the enzyme that catalyzes the formation of uric acid and a purported source of reactive oxygen species. However, the available evidence does not support the premise that either uric acid or the activation of xanthine oxidase has direct injurious effects on the heart in the clinical setting. Xanthine oxidase inhibitors (allopurinol and oxypurinol) have had little benefit and may exert detrimental effects in patients with chronic heart failure in randomized controlled trials, and the more selective and potent inhibitor febuxostat increases the risk of cardiovascular death more than allopurinol. Instead, the available evidence indicates that changes in xanthine oxidase and uric acid are biomarkers of oxidative stress (particularly in heart failure) and that xanthine oxidase may provide an important source of nitric oxide that quenches the injurious effects of reactive oxygen species. A primary determinant of the cellular redox state is nicotinamide adenine dinucleotide, whose levels drive an inverse relationship between xanthine oxidase and sirtuin-1, a nutrient deprivation sensor that exerts important antioxidant and cardioprotective effects. Interestingly, sodium-glucose cotransporter 2 inhibitors induce a state of nutrient deprivation that includes activation of sirtuin-1, suppression of xanthine oxidase, and lowering of serum uric acid. The intermediary role of sirtuin-1 in both uric acid-lowering and cardioprotection may explain why, in mediation analyses of large-scale cardiovascular trials, the effect of sodium-glucose cotransporter 2 inhibitors to decrease serum uric acid is a major predictor of the ability of these drugs to decrease serious heart failure events.

Inflammatory response of uric acid produced by Porphyromonas gingivalis gingipains

Uric acid is a potential metabolite that serves as a danger-associated molecular pattern (DAMP) and induces inflammatory responses in sterile environments. Porphyromonas gingivalis is a keystone periodontopathogen, and its gingipain proteases play a critical role in the pathogenesis of periodontitis. In this study, we demonstrate that P. gingivalis gingipains play a role in THP-1 macrophage uric acid production by increasing the expression and activity of xanthine oxidoreductase (XOR). Uric acid sodium salt induces caspase-1 activation, cell death, and the expression of proinflammatory cytokines, including IL-1α, IL-6, and IL-8, in the human keratinocyte HOK-16B cell line. Our results suggest that gingipain-induced uric acid can mediate inflammation in periodontal tissue cells.

Markers of nutritional status and inflammation in transthyretin cardiac amyloidosis: association with outcomes and the clinical phenotype

Background: Patients with transthyretin (TTR) cardiac amyloidosis demonstrate cardiac cachexia with progression of their cardiomyopathy, which is characterised by malnutrition and a heightened inflammatory state. How best to measure this condition is less well characterised. We investigated differences in survival among patients with ATTR cardiac amyloidosis by nutritional status as defined by modified BMI (mBMI) and by inflammatory state as defined by serum uric acid.Methods and results: This study was a retrospective analysis of patients diagnosed with ATTR cardiac amyloidosis at a single tertiary medical centre. Baseline characteristics were compared by nutritional status as measured by mBMI and by inflammatory state as measured by serum uric acid. Kaplan-Meier survival analyses were used to compare nutritional status and inflammatory status for the composite outcome of death. Cox proportional hazards modelling was used to assess predictors of death in this cohort. Three hundred patients (mean age 75 ± 11) years, 84.3% male) were included. Those with low mBMI (<1185 kg/m² g/L) had shorter time to death (5.4 vs. 6.8 years, log rank p = .045) and those with elevated serum uric acid (>8.8 mg/dL) had shorter time to death (4.9 vs. 7.7 years, log rank p < .0001). Those with both low mBMI and elevated serum uric acid had the shortest time to death (4.3 years, log rank p = .005). In this cohort, mBMI was not a univariate predictor of death though there was a trend towards significance (HR 0.92, per 100 kg/m² g/L, 95% CI 0.828-1.016, p = .099). Serum uric acid was a univariate predictor of death (HR 1.27 per 1 mg/dL, 95% CI 1.114-1.455, p < .001). In multivariate Cox analysis, this association remained significant (HR 1.31 per 1 mg/dL increase, 95% CI 1.096-1.560, p = .003) as well as in a separate stepwise model controlling for potential confounders including daily diuretic use, uric acid lowering therapy, and renal dysfunction.Conclusions: Both nutritional status as measured by mBMI and inflammation as measured by serum uric acid are associated with survival in patients with TTR cardiac amyloidosis however only serum uric acid is an independent predictor of death.

Serum uric acid level and subclinical left ventricular dysfunction: a community-based cohort study

AIMS

Although serum uric acid (SUA) level is correlated with oxidative stress and serves as a marker of poor prognosis in heart failure patients, its possible association with subclinical left ventricular (LV) dysfunction has not been evaluated. This study aimed to investigate the association between SUA and subclinical LV dysfunction in a sample of a general population without overt cardiac disease.

METHODS AND RESULTS

We examined 1175 participants who underwent extensive cardiovascular health check-up including laboratory tests and speckle-tracking echocardiography to assess LV global longitudinal strain (GLS). The association of SUA concentration, as a continuous variable and a categorical variable using quartiles, with the presence of abnormal LVGLS was assessed. Mean age was 62 ± 12 years, and 656 (56%) were male participants. Mean SUA was 5.6 ± 1.3 mg/dL (25th-75th percentile, 4.6-6.5 mg/dL). The prevalence of abnormal LVGLS (greater than -18.6%) was greatest in the upper quartile of SUA. In multivariable analysis, SUA as a continuous variable was significantly associated with abnormal LVGLS [adjusted odds ratio (OR), 1.26 per 1 mg/dL; P = 0.008] independent of traditional cardiovascular risk factors, pertinent laboratory parameters and echocardiographic measures, and medications. In the categorical analysis, the upper quartile of SUA was independently associated with abnormal LVGLS in a fully adjusted model (adjusted OR, 2.28 vs. lowest quartile; P = 0.020).

CONCLUSIONS

In a sample of the general population, an elevated SUA was independently associated with subclinical LV dysfunction. Assessment of LVGLS may add important prognostic information in individuals with elevated SUA, even in the absence of overt cardiac disease.

Prognostic Value of Serum Uric Acid in Hospitalized Heart Failure Patients With Preserved Ejection Fraction (from the Japanese Nationwide Multicenter Registry)

Elevated serum uric acid (UA) is associated with an increased risk of cardiovascular disease and worse clinical outcome in patients with cardiovascular disease. Nevertheless, the prognostic value of serum UA level in hospitalized heart failure patients with preserved ejection fraction (HFpEF) has not been fully elucidated. The aim of this study was to investigate whether serum UA level on admission could be associated with subsequent mortality in hospitalized patients with HFpEF. We examined 516 consecutive hospitalized HFpEF (left ventricular ejection fraction ≥50%) patients with decompensated heart failure from our HFpEF-specific multicenter registry who had serum UA data on admission. The primary outcome of interest was all-cause death. During a median follow-up period of 749 (interquartile range 540 to 831) days, 90 (17%) patients died. Higher serum UA level was significantly related to increased incidence of all-cause death (p = 0.016). In addition, patients with higher serum UA (≥6.6 mg/dl, median) and plasma B-type natriuretic peptide (≥401.2 pg/ml, median) levels had the highest incidence of all-cause death in the groups (p = 0.002). In multivariable Cox regression analysis, serum UA was an independent determinant of mortality (hazards ratio 1.23, 95% confidence interval 1.10 to 1.39) even after adjustment for prespecified confounders, renal function and the use of diuretics before admission. In conclusions, higher admission serum UA was an independent determinant of mortality in hospitalized HFpEF patients. Our findings indicate the importance of assessing admission serum UA level for further risk stratification in hospitalized patients with HFpEF.

Abdominal Adiposity and Total Body Fat as Predictors of Cardiometabolic Health in Children and Adolescents With Obesity

Objective: We aimed to assess the role of adipose tissue distribution in cardiometabolic risk (in particular insulin sensitivity) in a population of children and adolescents with obesity. Methods: In this cross-sectional study, participants were 479 children and adolescents with obesity (322 boys and 157 girls) aged 3 to 18 years attending the Children's Hospital at Zhejiang University School of Medicine (Hangzhou, China). Clinical assessments included anthropometry, body composition (DXA scans), carotid artery ultrasounds, and OGTT. Insulin sensitivity was assessed using the Matsuda index. Participants were stratified into groups by sex and pubertal stage. Key predictors were DXA-derived android-to-gynoid-fat ratio (A/G) and total body fat percentage (TBF%). Results: Irrespective of sex and pubertal stage, there was a strong association between increasing A/G (i.e., greater abdominal adiposity) and lower insulin sensitivity. In multivariable models, every 0.1 increase in A/G was associated with a reduction in insulin sensitivity in prepubertal boys [-29% (95% CI -36%, -20%); p < 0.0001], pubertal boys [-13% (95% CI -21%, -6%); p = 0.001], and pubertal girls [-16% (95% CI -24%, -6%); p = 0.002]. In contrast, TBF% was not associated with insulin sensitivity when A/G was adjusted for, irrespective of pubertal stage or sex. In addition, every 0.1 increase in A/G was associated with increased likelihood of dyslipidemia in prepubertal boys [adjusted odds ratio (aOR) 1.62 (95% CI 1.05, 2.49)], impaired glucose tolerance in pubertal boys [aOR 1.64 (95% CI 1.07, 2.51)] and pubertal girls [aOR 1.81 (95% CI 1.10, 2.98)], and odds of NAFLD in both prepubertal [aOR 2.57 (95% CI 1.56, 4.21)] and pubertal [aOR 1.69 (95% CI 1.18, 2.40)] boys. In contrast, higher TBF% was only associated with higher fasting insulin and ALT in pubertal boys, being also predictive of NAFLD in this group [aOR 1.15 per percentage point (95% CI 1.06, 1.26)], but was not associated with the likelihood of other cardiometabolic outcomes assessed in any group. Conclusions: A/G is a much stronger independent predictor of cardiometabolic risk factors in children and adolescents with obesity in China, particularly glucose metabolism.

Malondialdehyde and Uric Acid as Predictors of Adverse Outcome in Patients with Chronic Heart Failure

In chronic heart failure (HF), some parameters of oxidative stress are correlated with disease severity. The aim of this study was to evaluate the importance of oxidative stress biomarkers in prognostic risk stratification (death and combined endpoint: heart transplantation or death). In 774 patients, aged 48-59 years, with chronic HF with reduced ejection fraction (median: 24.0 (20-29)%), parameters such as total antioxidant capacity, total oxidant status, oxidative stress index, and concentration of uric acid (UA), bilirubin, protein sulfhydryl groups (PSH), and malondialdehyde (MDA) were measured. The parameters were assessed as predictive biomarkers of mortality and combined endpoint in a 1-year follow-up. The multivariate Cox regression analysis was adjusted for other important clinical and laboratory prognostic markers. Among all the oxidative stress markers examined in multivariate analysis, only MDA and UA were found to be independent predictors of death and combined endpoint. Higher serum MDA concentration increased the risk of death by 103.0% (HR = 2.103; 95% CI (1.330-3.325)) and of combined endpoint occurrence by 100% (HR = 2.000; 95% CI (1.366-2.928)) per μmol/L. Baseline levels of MDA in the 4^th quartile were associated with an increased risk of death with a relative risk (RR) of 3.64 (95% CI (1.917 to 6.926), p < 0.001) and RR of 2.71 (95% CI (1.551 to 4.739), p < 0.001) for the occurrence of combined endpoint as compared to levels of MDA in the 1^st quartile. Higher serum UA concentration increased the risk of death by 2.1% (HR = 1.021; 95% CI (1.005-1.038), p < 0.001) and increased combined endpoint occurrence by 1.4% (HR = 1.014; 95% CI (1.005-1.028), p < 0.001), for every 10 μmol/L. Baseline levels of UA in the 4^th quartile were associated with an increased risk for death with a RR of 3.21 (95% CI (1.734 to 5.931)) and RR of 2.73 (95% CI (1.560 to 4.766)) for the occurrence of combined endpoint as compared to the levels of UA in the 1^st quartile. In patients with chronic HF, increased MDA and UA concentrations were independently related to poor prognosis in a 1-year follow-up.

Uric acid is a key player in salt-induced endothelial dysfunction: the therapeutic role of Stigma maydis (corn silk) extract

Hyperuricemia has been implicated in the pathogenesis and complications of cardiovascular diseases with associated elevated oxidant events. There is evidence that excessive salt intake results in cardiometabolic disturbances but the mechanism is elusive. Also, Stigma maydis (corn silk) is noted for its antioxidant properties among other beneficial roles. This study, therefore, aimed to establish the effect of high-salt diet (SD) on uric acid (UA) production and the role of S. maydis in salt-induced phenotypes. Four groups of randomly selected rats (n = 5) were fed with normal rat feed, corn silk extract (500 mg/kg), SD (8%) and corn silk extract plus high-salt feed. After 6 weeks of the experimental procedure, each animal was anesthetized by exposure to chloroform vapor and blood samples collected by cardiac puncture. Data were expressed in means ± SEM and p values <0.05 were accepted as significant. SD resulted in reduced plasma superoxide dismutase (SOD), nitric oxide (NO), and glutathione peroxidase (GPx) but not endothelial nitric oxide synthase. Also, plasma UA and vascular cell adhesion molecule-1 (VCAM-1) increased in the SD group compared with control. However, S. maydis extract in the SD-exposed group increased NO and GPx and not SOD. Also, S. maydis extract attenuated UA and VCAM-1. In conclusion, high-salt intake may initiate deleterious cardiovascular events through UA-dependent mechanism and S. maydis extract has therapeutic potential in high-salt-induced oxidative damage and/or UA-dependent endothelial pathologies.

Association of serum uric acid change with mortality, renal function and diuretic dose administered in treatment of acute heart failure

BACKGROUND AND AIMS

Hyperuricemia is reportedly associated with poor outcome in acute heart failure (AHF). The association between changes in Uric acid (UA) levels with renal function change, diuretic doses, and mortality in patients with AHF were studied.

METHODS AND RESULTS

Consecutive patients hospitalized with AHF were reviewed (n = 535). UA levels were measured at admission and either at discharge or on approximately the seventh day of admission. Patients with an UA change in the top tertile were defined as having an increase (UA-increase) and were compared to those outside the top tertile (non-UA-increase). The endpoint was all-cause mortality, with a mean follow-up duration of 22.2 months. Patients in the UA-increase group presented with greater creatine increase (P < 0.001), and were administered a higher average daily dose of loop diuretic (P = 0.016) compared with the non-UA-increase group. In-hospital UA-increase was associated with higher risk of mortality even after adjusting for confounding variables including creatine change and diuretic dosage [harzard ratio (HR) 1.53, 95% confidence interval (CI) 1.02-2.30, P = 0.042]. In patients with hyperuricemia on admission, UA-increase was associated with increased mortality (adjusted HR 2.21, 95% CI 1.38-3.52, P = 0.001). Whereas, in those without admission hyperuricemia, UA-increase had no significant association with mortality.

CONCLUSIONS

An increase in UA during in-hospital treatment is associated with an increase in creatine levels and daily diuretic dose. Mortality associated with increased UA is restricted to patients who already have hyperuricemia at admission. A combination of UA levels at admission and UA changes on serial assessment during hospitalization may be additional value in the risk stratification of AHF patients.

An Appraisal of Biomarker-Based Risk-Scoring Models in Chronic Heart Failure: Which One Is Best?

PURPOSE OF REVIEW

While prediction models incorporating biomarkers are used in heart failure, these have shown wide-ranging discrimination and calibration. This review will discuss externally validated biomarker-based risk models in chronic heart failure patients assessing their quality and relevance to clinical practice.

RECENT FINDINGS

Biomarkers may help in determining prognosis in chronic heart failure patients as they reflect early pathologic processes, even before symptoms or worsening disease. We present the characteristics and describe the performance of 10 externally validated prediction models including at least one biomarker among their predictive factors. Very few models report adequate discrimination and calibration. Some studies evaluated the additional predictive value of adding a biomarker to a model. However, these have not been routinely assessed in subsequent validation studies. New and existing prediction models should include biomarkers, which improve model performance. Ongoing research is needed to assess the performance of models in contemporary patients.

Relationship between platelet count and platelet width distribution and serum uric acid concentrations in patients with untreated essential hypertension

Hematological parameters have emerged as independent determinants of high serum concentrations of uric acid (UA) and predictive factors in the evaluation of the total cardiovascular risk in patients with essential hypertensive. Here, we have investigated the possible relationships between hematological factors and serum uric acid levels in hypertensive patients recruited as part of Mashhad Stroke and Heart Atherosclerotic Disorders cohort study. Two-thousand three-hundred and thirty-four hypertensive individuals were recruited from this cohort and these were divided into two groups; those with either high or low serum UA concentrations. Demographic, biochemical, and hematological characteristics of population were evaluated in all the subjects. Logistic-regression analysis was performed to determine the association of hematological parameters with hypertension (HTN). Of the 2334 hypertensive subjects, 290 cases had low UA, and 2044 had high serum UA concentrations. Compared with the low UA group, the patients with high serum UA, had higher values for several hematological parameters, whilst platelet counts (PLT) were lower. Multiple linear regression analysis showed that PLT and serum high sensitivity-c reactive protein (hs-CRP) were correlated with serum UA level. Stepwise multiple logistic regression model confirmed that platelet distribution width (PDW) and gender were independent determinant of a high serum UA. PDW and PLT appear to be independently associated with serum UA level in patients with HTN. © 2018 BioFactors, 44(6):532-538, 2018.

Gender-specific association of serum uric acid levels and cardio-ankle vascular index in Chinese adults

BACKGROUND

Little is known about the relationship between serum uric acid (SUA) and cardio-ankle vascular index (CAVI) in Chinese population. Therefore, we aimed to investigate the gender difference in the association of SUA and CAVI in a southwestern Chinese population.

METHODS

Data were obtained from subjects via routine physical examinations in the Public Health Center of our hospital between 2011 and 2014 in Chongqing. The data included completed anthropometry and blood biochemical indicators. The CAVI were recorded using an automatically VaseraVS-1000 vascular screening system.

RESULTS

We found females with hyperuricemia (HUA) had significantly higher CAVI than women with normal SUA (8.45 ± 1.40 vs 7.67 ± 1.15, P<0.05). Then we defined high CAVI as CAVI≥9 m/s, and compared the percentage of high CAVI, we found women with HUA had higher percentage of high CAVI than women with normal SUA (26.83% vs 9.38%, P<0.05). Those differences were not significant in males. Also, the logistic regression analysis found age and hypertension were major independent risk factors associated with high CAVI in both genders. HUA and hyperglycemia were independently associated with high CAVI in females with an OR of 3.65, 95%CI (1.37-9.73) and 3.02, 95%CI (1.38-6.63) respectively. However, these significant associations were not be found in males.

CONCLUSIONS

Our data showed positive associations between elevated SUA levels and higher CAVI risk in the inland Chinese females, but not in males. The reason for the gender differences were still unclear, sex hormones may play a role. Further prospective studies including detailed personal information and multicenter were required.

Levels of serum uric acid at admission for hypoglycaemia predict 1-year mortality

AIMS

Hypoglycaemia represents a critical burden with clinical and social consequences in the management of diabetes. Serum uric acid (SUA) has been associated with cardiovascular diseases (CVD), but no conclusive findings are available nowadays in patients suffering from hypoglycaemia. We investigated whether SUA levels at the time of hypoglycaemia could predict all-cause mortality after 1-year follow-up.

METHODS

In total, 219 patients admitted to the Emergency Department (ED) of Ospedale Policlinico S. Martino of Genoa (Italy) have been enrolled between January 2011 and December 2014. The primary endpoint of the study consisted in determining whether SUA levels at the time of ED admission could predict the occurrence of death after 1 year.

RESULTS

The majority of patients were diabetic, especially type 2. CVD and chronic kidney disease were prevalent comorbidities. By a cut-off value obtained by the receiver operating characteristic curve analysis, a Kaplan-Meier analysis demonstrated that patients with SUA levels > 5.43 mg/dL were more prone to death after 1 year compared to those with lower SUA levels. The risk of death increased with high SUA levels both in the univariate and the multivariate models including estimated glomerular filtration rate, C-reactive protein, type of diabetes, and age-adjusted Charlson comorbidity index.

CONCLUSIONS

SUA could be useful as a predictor of 1-year mortality in hypoglycaemic patients, irrespective of severe comorbidities notably increasing the risk of death in these frail patients.

Dietary Magnesium Intake and Hyperuricemia among US Adults

To assess the association between dietary magnesium intake and hyperuricemia in United States (US) adults, we extracted 26,796 US adults aged 20–85 years from the National Health and Nutrition Examination Survey (NHANES) in 2001–2014. All dietary intake was measured through 24 h dietary recall method. Multivariable logistic regression analysis was performed to investigate the association between magnesium intake and hyperuricemia after adjusting for several important confounding variables. When compared to the lowest quintile (Q1), for male, adjusted odds ratios (ORs) of hyperuricemia in the second quintile (Q2) to the fifth quintile (Q5) of the magnesium intake were 0.83 (95% CI: 0.72–0.95), 0.74 (0.64–0.85), 0.78 (0.67–0.90), and 0.70 (0.58–0.84, p for trend = 0.0003), respectively. For female, OR was 0.75 (0.62–0.90) in the fourth quintile (Q4) (p for trend = 0.0242). As compared to Q4 of magnesium intake (contains recommended amount), the relative odds of hyperuricemia were increased by 1.29 times in Q1 (OR = 1.29, 1.11–1.50) in male. The ORs were 1.33 (1.11–1.61) in Q1, 1.27 (1.07–1.50) in Q2 in female. Our results indicated that increased magnesium intake was associated with decreased hyperuricemia risk. It also indicated the importance of recommended dietary allowance (RDA) of magnesium and the potential function of magnesium intake in the prevention of hyperuricemia.

Limited Added Value of Circulating Inflammatory Biomarkers in Chronic Heart Failure

OBJECTIVES

This study sought to evaluate whether a panel of biomarkers improved prognostication in patients with heart failure (HF) and reduced ejection fraction of ischemic origin using a systematized approach according to suggested requirements for validation of new biomarkers.

BACKGROUND

Modeling combinations of multiple circulating markers could potentially identify patients with HF at particularly high risk and aid in the selection of individualized therapy.

METHODS

From a panel of 20 inflammatory and extracellular matrix biomarkers, 2 different biomarker panels were created and added to the Seattle HF score and the prognostic model from the CORONA (Controlled Rosuvastatin Multinational Trial in Heart Failure) study (n = 1,497), which included conventional clinical characteristics and C-reactive protein and N-terminal pro-B-type natriuretic peptide. Interactions with statin treatment were also assessed.

RESULTS

The two models-model 1 (endostatin, interleukin 8, soluble ST2, troponin T, galectin 3, and chemokine [C-C motif] ligand 21) and model 2 (troponin T, soluble ST2, galectin 3, pentraxin 3, and soluble tumor necrosis factor receptor 2)-significantly improved the CORONA and Seattle HF models but added only modestly to their Harrell's C statistic and net reclassification index. In addition, rosuvastatin had no effect on the levels of a wide range of inflammatory and extracellular matrix markers, but there was a tendency for patients with a lower level of biomarkers in the 2 panels to have a positive effect from statin treatment.

CONCLUSIONS

In the specific HF patient population studied, a multimarker approach using the particular panel of biomarkers measured was of limited clinical value for identifying future risk of adverse outcomes.

The link between insulin resistance parameters and serum uric acid is mediated by adiposity

BACKGROUND AND AIMS

Conflicting results suggest a link between serum uric acid (SUA), inflammation and glucose/insulin homeostasis; however, the role of adiposity in this relationship is not clear. Therefore, we evaluated the role of different adiposity factors, including central body mass index (BMI), peripheral waist circumference (WC), and visceral adiposity [visceral adipose tissue (apVAT)], on the association between SUA, inflammation and glucose/insulin homeostasis among US adults.

METHODS

Data were extracted from the 2005-2010 US National Health and Nutrition Examination Surveys. Overall, 16,502 participants were included in the analysis (mean age = 47.1 years, 48.2% men). Analysis of co-variance and "conceptus causal mediation" models were applied, while accounting for survey design.

RESULTS

Corrected models showed that subjects with higher SUA levels have a less favorable profile of inflammation and glucose/insulin homeostasis parameters (all p < 0.001). We found that all our potential mediators (BMI, WC and apVAT) had an impact (to various extents) on the link between variables, including serum C-reactive protein (CRP), apolipoprotein-B (apoB), insulin resistance markers, 2-h blood glucose (2hG) and triglyceride, and fasting blood glucose (FBG) (TyG) index (all p < .001), while none of the potential mediators (BMI, apVAT, WC) had an impact on the link between FBG and glycated hemoglobin with SUA (all p > 0.05). We have found that all of our mediators partially mediated the link between inflammation and glucose/insulin homeostasis parameters and SUA. Of note, apVAT fully mediated the association between SUA and 2hG.

CONCLUSIONS

By applying advanced statistical techniques, we shed light on the complex link of SUA with inflammation and glucose/insulin homeostasis and quantify the role of adiposity factors in that link.

Metabolic modeling helps interpret transcriptomic changes during malaria

Disease represents a specific case of malfunctioning within a complex system. Whereas it is often feasible to observe and possibly treat the symptoms of a disease, it is much more challenging to identify and characterize its molecular root causes. Even in infectious diseases that are caused by a known parasite, it is often impossible to pinpoint exactly which molecular profiles of components or processes are directly or indirectly altered. However, a deep understanding of such profiles is a prerequisite for rational, efficacious treatments. Modern omics methodologies are permitting large-scale scans of some molecular profiles, but these scans often yield results that are not intuitive and difficult to interpret. For instance, the comparison of healthy and diseased transcriptome profiles may point to certain sets of involved genes, but a host of post-transcriptional processes and regulatory mechanisms renders predictions regarding metabolic or physiological consequences of the observed changes in gene expression unreliable. Here we present proof of concept that dynamic models of metabolic pathway systems may offer a tool for interpreting transcriptomic profiles measured during disease. We illustrate this strategy with the interpretation of expression data of genes coding for enzymes associated with purine metabolism. These data were obtained during infections of rhesus macaques (Macaca mulatta) with the malaria parasite Plasmodium cynomolgi or P. coatneyi. The model-based interpretation reveals clear patterns of flux redistribution within the purine pathway that are consistent between the two malaria pathogens and are even reflected in data from humans infected with P. falciparum. This article is part of a Special Issue entitled: Accelerating Precision Medicine through Genetic and Genomic Big Data Analysis edited by Yudong Cai & Tao Huang.

Prevalence of Hyperuricemia in Patients With Acute Heart Failure With Either Reduced or Preserved Ejection Fraction

The relation between uric acid (UA) and heart failure has been described; however, there is little detail concerning acute heart failure (AHF) in patients with reduced versus preserved ejection fraction heart failure (HFrEF, HFpEF). We studied 324 consecutive AHF patients screened from interventional Diur-HF Trial (NCT01441245) from January 2011 to February 2016, and divided into HFrEF (EF <50%) and HFpEF (EF ≥50%). We defined hyperuricemia as serum UA ≥7.0 mg/dL in men and ≥6 mg/dL in women. Patients were followed up for 6 months after discharge. The primary outcome was heart failure hospitalization or death. Among 173 HFrEF and 151 HFpEF cases, hyperuricemia was found in 43% and 57%, respectively (p = 0.01). Hyperuricemia was also more frequent in women (74% vs 60%; p = 0.008), those with diabetes (39% vs 19%; p <0.001), hypertension (62% vs 43%; p = 0.001), and atrial fibrillation (48% vs 34%; p = 0.01). In patients with HFrEF, univariate analysis found that hyperuricemia (hazard ratio [HR] 1.48, 95% confidence interval [CI] 1.02 to 2.15; p = 0.04) and congestion score ≥3 (HR 2.83, 95% CI 1.52 to 5.28; p <0.001) were associated with the primary end point; after adjustment, only congestion score ≥3 (HR 2.08, 95% CI 1.06 to 4.10; p = 0.03) confirmed this trend. Conversely, in patients with HFpEF, hyperuricemia was the only significant predictor of the primary end point both in univariate (HR 2.25, 95% CI 1.44 to 3.50; p <0.001) and multivariate analyses (HR 2.38, 95% CI 1.32 to 4.28; p = 0.004). In conclusion, in AHF hyperuricemia is common in both in HFrEF and in HFpEF. In the HFpEF subgroup, hyperuricemia was the only independent predictor of heart failure hospitalization or death.

Serum Urate Levels Predict Joint Space Narrowing in Non-Gout Patients With Medial Knee Osteoarthritis

OBJECTIVE

The pathogenesis of osteoarthritis (OA) includes both mechanical and inflammatory features. Studies have implicated synovial fluid uric acid (UA) as a potential OA biomarker, possibly reflecting chondrocyte damage. Whether serum UA levels reflect/contribute to OA is unknown. We investigated whether serum UA levels predict OA progression in a non-gout knee OA population.

METHODS

Eighty-eight patients with medial knee OA (body mass index [BMI] <33 kg/m² ) but without gout were studied. Baseline serum UA levels were measured in previously banked serum samples. At 0 and 24 months, patients underwent standardized weight-bearing fixed-flexion posteroanterior knee radiography to determine joint space width (JSW) and Kellgren/Lawrence grades. Joint space narrowing (JSN) was calculated as the change in JSW from 0 to 24 months. Twenty-seven patients underwent baseline contrast-enhanced 3T knee magnetic resonance imaging for assessment of synovial volume.

RESULTS

Serum UA levels correlated with JSN values in both univariate (r = 0.40, P < 0.01) and multivariate (r = 0.28, P = 0.01) analyses. There was a significant difference in mean JSN after dichotomization at a serum UA cut point of 6.8 mg/dl, the solubility point for serum urate, even after adjustment (JSN of 0.90 mm for a serum UA ≥6.8 mg/dl and 0.31 mm for a serum UA <6.8 mg/dl; P < 0.01). Baseline serum UA levels distinguished progressors (JSN >0.2 mm) and fast progressors (JSN >0.5 mm) from nonprogressors (JSN ≤0.0 mm) in multivariate analyses (area under the receiver operating characteristic curve 0.63 [P = 0.03] and 0.62 [P = 0.05], respectively). Serum UA levels correlated with the synovial volume (r = 0.44, P < 0.01), a possible marker of JSN, although this correlation did not persist after controlling for age, sex, and BMI (r = 0.13, P = 0.56).

CONCLUSION

In non-gout patients with knee OA, the serum UA level predicted future JSN and may serve as a biomarker for OA progression.

Serum uric acid on admission predicts in-hospital mortality in patients with acute coronary syndrome

BACKGROUND

Despite the association between uric acid and cardiovascular disease has been known for decades, the prognostic value of serum uric acid (UA) in all clinical manifestations of acute coronary syndrome (ACS), namely ST-elevation myocardial infarction (STEMI), NSTEMI and unstable angina, has not been definitively assessed.

METHODS

This retrospective analysis included patients from previous SPAI and FAMI studies with the aim to investigate the association between serum uric acid and major adverse cardiovascular events at 180days from hospital admission.

RESULTS

1548 patients were considered and divided in four groups, according UA concentration. Uricemia was significantly associated with gender, BMI, arterial hypertension, HDL-cholesterol, triglycerides, metabolic syndrome and glomerular filtration rate in univariate analysis. Multivariate logistic regression indicated that UA >6.0mg/dL on admission increased the risk of in-hospital mortality in overall population (OR 2.9, 95%CI 1.4-6.1; p=0.0057) and in patients with de novo ACS (OR 3.2, 95%CI 1.5-6.8; p=0.0033). Comparable results were also obtained after adjusting the model for age, gender, body mass index, glomerular filtration rate, metabolic syndrome, acute revascularization and ethnicity. A positive correlation was observed between UA and C reactive protein concentrations in in-hospital deaths only (rho 0.41, p=0.027).

CONCLUSION

In patients with acute coronary syndrome, uricemia levels above the current international reference limit (6.0mg/dl) were associated with in-hospital mortality, independently from ethnicity and renal function.

Serum Uric Acid level in the severity of Congestive Heart Failure (CHF)

BACKGROUND AND OBJECTIVE

It has been observed that in a clinical condition like hypoxemia there is an increase in the serum Uric acid level. The objective of our study was to find out the relationship between serum uric acid levels in the severity of Heart failure.

METHODS

We analyze 285 patients with a diagnosis of Congestive heart failure admitted in Lady Reading Hospital Peshawar from March 1st to August 2016. Age group of patients was 17- 67 years. New York Health Association (NYHA) scoring were used to access the severity of Congestive Heart Failure. Serum UA level >7.0 mg/dl was considered high.

RESULTS

Total 285 patients with CHF were analyzed with a mean age of 54±2.8 years in which males were 65.96% and 34.03% were female. 40% were in class II of New York Health Association (NYHA), 32.63% in class III and 25.61% in class IV and 1.75% were in class I. Out of 285, 59.29% met the definition of hyperuricemia. In which 83.43% were male and 16.57% were female. Most of the Hyperuricemic patients 62.13% were in age group of 51- 60 years, with a mean age of 57±4.5 years. We found a significant correlation between uric acid level and BNP (p= <0.001), and use of diuretics (p=<0.001). 34.93% of the Hyperuricemic CHF patients were in NYHA III and NYHA IV whose SUA was above 8 mg/dl as compared to 31.57% Hyperuricemic CHF patients whose SUA was below 8 mg/dl.

CONCLUSION

High serum Uric acid was observed in 59.29% of patients with CHF. The observed significant correlation between UA level and some established prognostic markers in these patients may indicate that serum UA could provide additional prognostic information in this population. SUA as a marker can be measured anywhere at a low cost to help identify high-risk patients with CHF. Lowing uric acid is expected to be a new approach for prevention and therapy of HF.