Serum uric acid / serum creatinine ratio as a predictor of cardiovascular events. Detection of prognostic cardiovascular cut-off values

Serum Uric Acid Is Associated with Insulin Resistance in Non-Diabetic Subjects

Background: Glucose metabolism disorders are major contributors to morbidity and mortality. Elevated serum uric acid (SUA) is closely linked to the cardiometabolic consequences of glucose metabolism disorders, various other comorbidities, and mortality. In this study, we explore the relationship between SUA and fasting plasma glucose (FPG), insulin levels, and insulin resistance in an older Finnish adult cohort. Methods: We used data from the GOAL (GOod Ageing in Lahti region) study-a prospective, population-based study of Finnish individuals aged 52-76 years. A total of 2322 non-diabetic subjects were included in the study. Data of SUA, FPG, and other laboratory parameters, comorbidities, lifestyle habits, and socioeconomic factors were collected. Subjects with SUA values of >410 μmol/L (≈6.9 mg/dL; 75th percentile) were regarded as hyperuricemic. We investigated the relationship between SUA and FPG, insulin levels, and insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.65]. Results: We found statistically significant sex-, age- and BMI-adjusted small to moderate relationships (Cohen's standard for β values above 0.10 and 0.30, respectively) between SUA and FPG, insulin levels, and insulin resistance in the whole study population as well as in the female and male subgroups. The higher the SUA level, the higher the HOMA-IR [(adjusted β = 0.21 (95% CI: 0.17 to 0.25)], and it rises drastically if SUA is above 400 μmol/L (≈6.7 mg/dL). The probability of a subject having insulin resistance is related to SUA level. Conclusions: Hyperuricemia is associated with elevated FPG and insulin resistance, emphasizing the importance of addressing both conditions. Further research may explore hyperuricemia treatment's role in preventing glucose metabolism disorders and their cardiometabolic consequences.

Clinical outcomes in patients with cardiorenal multimorbidity: the role of serum uric acid/serum creatinine ratio

INTRODUCTION

Serum uric acid (SUA), the final product of purine metabolism, is an independent risk factor for cardiovascular (CV) disease. Since SUA levels depend on renal function, SUA to serum creatinine ratio (SUA/sCr) is emerging as a more specific biomarker of CV risk.

AIM

To evaluate in hospitalized patients with cardiorenal multimorbidity (CRM) if the SUA/sCr ≥ 5.35 is associated with clinical outcomes. The primary outcome was in-hospital mortality. The secondary outcome was the composite of all-cause of mortality and adverse clinical events.

METHODS

We conducted a retrospective review of medical records from consecutive CRM inpatients admitted to the medical ward. The composite endpoint was calculated as all-cause mortality and adverse clinical events such as acute coronary syndrome, stroke, infections, and renal replacement therapy.

RESULTS

In our cohort, 141 patients (mean age of 75.6 ± 10.2 years) were identified with CRM. In-hospital mortality occurred in 17 patients (16%), and 64 patients (60.4%) experienced adverse clinical outcomes. Among the 106 patients, 20 (18.9%) had an SUA/sCr ≥ 5.35, while 86 (81.1%) had an SUA/sCr < 5.35. Male gender was significantly associated with SUA/sCr ≥ 5.35 (p = 0.007). In-hospital mortality was significantly higher in patients with SUA/sCr ≥ 5.35 (p = 0.010), and a positive correlation with adverse clinical outcomes was documented in this subgroup (p = 0.012).

CONCLUSION

in patients with CRM, SUA/sCr ≥ 5.35 is associated with increased in-hospital mortality and worse clinical outcomes. The ratio and related cut-off value of SUA/sCr could represent a useful biomarker to assess in-hospital complications in CRM patients.

Hyperuricemia, A new cardiovascular risk

BACKGROUND AND AIMS

Hyperuricemia is strongly linked to increased cardiovascular risk, including hypertension, coronary artery disease, arrythmia, and heart failure. Uric acid, as the end-product of purine metabolism, plays a critical role in cellular processes, but elevated levels can drive inflammation and oxidative stress. This review aims to emphasize the robust association between hyperuricemia and cardiovascular diseases, exploring whether uric acid-lowering therapies can mitigate cardiovascular events and improve patient outcomes.

METHODS AND RESULTS

A comprehensive review of PubMed sources was conducted, underscoring the significant link between high uric acid levels and cardiovascular events, particularly in patients with gout. Gender differences were observed, where premenopausal women have lower uric acid levels, likely due to hormonal effects, suggesting the potential need for gender-specific definitions in assessing cardiovascular risk. Epidemiological studies demonstrate a consistent correlation between hyperuricemia and adverse cardiovascular outcomes. However, interventional trials using xanthine oxidase inhibitors, such as allopurinol and febuxostat, have shown mixed results regarding their impact on reducing cardiovascular events. Additionally, emerging evidence suggests a "xanthine oxidase withdrawal syndrome" upon discontinuation of these therapies, highlighting the need for cautious management.

CONCLUSION

The strong association between elevated uric acid levels and cardiovascular diseases is well-documented. While lowering uric acid shows potential for reducing cardiovascular risk, current evidence from interventional trials remains inconclusive. Future research should focus on patient-specific therapeutic strategies, particularly for those at high cardiovascular risk with hyperuricemia and/or gout, to better define the benefits of targeted treatments.

Serum Uric Acid/Serum Creatinine Ratio and Chronic Vascular Lesions on Renal Biopsy: A Retrospective Observational Study

INTRODUCTION

Increased serum uric acid (SUA) levels are found in cardiovascular and kidney diseases, associated with the development of vascular injury. Uric acid stimulates the inflammatory pathways, promotes vascular smooth muscle cells proliferation, activates renin-angiotensin system leading to the development and progression of vascular damage. Renal function-normalized uric acid [SUA to serum creatinine ratio (SUA/SCr)] has been suggested to be a better indicator of uric acid.

AIM

To investigate the correlation between SUA level and SUA/SCr in the development of chronic and vascular lesions (CVL) in patients with primary glomerulonephritis (GN).

METHODS

A retrospective observational study was conducted in 95 consecutive renal native biopsies performed at Policlinico Umberto I of Rome (Italy). Patient inclusion criteria were age ≥ 18 years, a renal biopsy confirming diagnosis of primary GN, the availability of complete demographic, clinical, pathological, and laboratory data.

RESULTS

Median SCr was 1.06 mg/dl (IQR 0.77;1.70) with a median eGFR of 70.40 ml/min (IQR 40.40;105). Median SUA was 5.90 mg/dl (IQR 4.30;6.90) and median SUA/SCr was 4.70 (IQR 3.20;6.80). CVL were reported in 56 (58.9%) patients. Median SUA/SCr was significantly lower in patients with CVL than patients without CVL [3.95 (IQR 2.65;6) vs 5.90 (IQR 4.30;7.20), p<0.01]. Logistic regression analysis showed that SUA/SCr ≤ 4.05 [OR 5.451 (95% CI 1.222;24.325), p<0.05] was independently associated with CVL.

CONCLUSIONS

CVL play a crucial role in the progression of kidney disease. SUA/SCr ≤ 4.05 is associated with CVL in patients with primitive GN.

Is Serum Uric Acid to Creatinine Ratio Associated with Hypertension and Metabolic Syndrome in Children with Obesity?

Childhood obesity is a global health problem with increasing prevalence, leading to long-term cardiovascular complications. Research conducted on adults has established a correlation between serum uric acid to creatinine ratio (SUA/Cr) and metabolic syndrome (MetS) components. The study investigates the relationship between SUA/Cr and hypertension (HT) and MetS components in children with obesity.A total of 103 children with obesity who underwent ambulatory blood pressure measurement (ABPM) were included the study and patients were divided into two groups "HT" (n=60) and "Normal" (n=43). Demographic, anthropometric, and laboratory characteristics were retrospectively analyzed.The study included 103 children (42 female, 61 male) with a mean age of 13.7±2.9 years. HT prevalence was significantly higher in patients with severe obesity and dyslipidemia (p=0.045, p=0.01). Males exhibited significantly higher SUA/Cr than females (p<0.001). However, SUA/Cr showed no significant differences between patients with and without HT, MetS, dyslipidemia, or hyperglycemia (p=0.69, p=0.64, p=0.90, p=0.37). Furthermore, linear regression analysis did not establish a significant effect of SUA/Cr on ABPM parameters (p>0.05).In our cohort, no significant association was found between SUA/Cr and HT, as well as MetS components in children with obesity. These findings highlight the need for further investigation into the complex mechanisms regulating uric acid metabolism, obesity, and cardiovascular risk in children.

Current updates and future perspectives in uric acid research, 2024

Uric acid, the final product of purine metabolism, plays a significant role in hypertension Research on uric acid has advanced significantly, particularly regarding its links to hypertension and cardiovascular disease (CVD). Our 2023 review covered the relationship between uric acid, hypertension; and CVD, however, numerous new studies have emerged since then. This paper provides an update, summarizing recent findings over the past two years on hyperuricemia and its association with hypertension, preeclampsia, arteriosclerosis, kidney disease, sleep-disordered breathing, CVD, and so on. Hyperuricemia, often driven by reduced uric acid excretion or increased production, is influenced by genetic factors and lifestyle habits, including high-purine foods, alcohol, and fructose intake. While hyperuricemia has been proposed to contribute to hypertension and CVD through mechanisms like inflammasome activation and oxidative stress, its causal role remains debated. Further clinical and basic science studies on hyperuricemia and purine metabolism are necessary to clarify its impact on CVD and guide therapeutic approaches.

Newly defined biomarker for the no reflow phenomenon in patients with non-ST elevation acute coronary syndrome; uric acid to creatinine ratio

BACKGROUND

The present study aimed to investigate whether newly defined serum uric acid (SUA) to serum creatinine ratio (SUA/SCr) predicts no-reflow phenomenon (NRP) development in patients with non-ST-elevated acute coronary syndrome (NSTE-ACS).

METHODS

The study group was divided into two groups: those who developed NRP and those who did not. Complete blood counts, SUA, serum creatinine, C-reactive protein (CRP) and albumin were obtained at admission. The SUA/SCr, SUA to albumin ratio (UAR), C-reactive protein to albumin ratio (CAR) and systemic immune inflammation (SII) index values of all patients were calculated and their relationships with NRP were evaluated.

RESULTS

Patients with NRP had higher mean SUA/SCr ratio (7.19 ± 2.14 vs 5.30 ± 1.70, p < 0.001), mean UAR (1.73 ± 0.69 vs 1.38 ± 0.47, p < 0.001), median CAR (1.73 vs 1.54, p = 0.002), and median SII index (861.9 vs 730.9, p = 0.015) levels than in those who did not develop NRP. According to multivariant analysis models, SUA/SCr ratio, UAR, CAR and SII index were found to be independent predictors of NRP development (p < 0.05 for all) but only the area under the curve (AUC) for SUA/SCr ratio (AUC = 0.73, p < 0.001) was above the 0.70 proficiency level, performing markedly better than the other evaluated parameters. A SUA/SCr ratio ≥5.34 predicted the NRP with 75% sensitivity and 55% specificity.

CONCLUSION

SUA/SCr ratio can be used as a reliable marker in prediction the development of NRP in NSTE-ACS patients.

Evaluation of Individual Cardiovascular Risk in Pre-Dialysis CKD Patients by Using the Ratio of Calcium-Phosphorus Product to Estimated Glomerular Filtration Rate (Ca × P/eGFR)

BACKGROUND

Chronic kidney disease (CKD) patients have an increased risk of cardiovascular disease (CVD), necessitating effective risk assessment methods. This study evaluates the calcium-phosphorus product (Ca × P) to estimated glomerular filtration rate (Ca × P/eGFR) ratio as a potential biomarker for predicting CV risk in pre-dialysis CKD patients.

METHODS

Eighty-four CKD patients in stages G1-G4, according to the KDIGO criteria, were classified into CVD (n = 43) and non-CVD (n = 41) groups. Biochemical parameters, including serum creatinine (SCr), blood urea nitrogen (BUN), calcium (Ca), inorganic phosphate (Pi), parathyroid hormone (PTH), alkaline phosphatase (ALP), Ca × P, eGFR, and the Ca × P/eGFR ratio, were measured and calculated. Statistical analyses were performed to identify predictors of CV risk and evaluate the diagnostic reliability of the Ca × P/eGFR ratio for predicting the risk.

RESULTS

Significant differences were observed in SCr, BUN, eGFR (p < 0.001), and the Ca × P/eGFR ratio (p = 0.007) between the groups. Regression analysis indicated the Ca × P/eGFR ratio as a significant CVD risk predictor (p = 0.012, OR = 1.206, 95% CI: 1.042-1.395). Receiver Operating Characteristic (ROC) curve analysis revealed an AUC of 0.751 (p < 0.001, 95% CI: 0.645-0.857), with a sensitivity and specificity of the method of 74.4% and 70.7%, respectively. Significant correlations were found between the Ca × P/eGFR ratio and SCr, BUN, UA, Ca, Pi, PTH, and ALP.

CONCLUSIONS

The Ca × P/eGFR ratio may serve as a significant predictor of CVD risk in pre-dialysis CKD patients, suggesting that its integration into routine evaluations could enhance CV risk stratification and management.

Nonlinear association between the serum uric acid-to-creatinine ratio and all cause mortality in patients with hypertension: a ten-year cohort study using the NHANES database

The serum uric acid-to-creatinine ratio (UCR) may be a simple method for assessing xanthine oxidase overactivation, which may contribute to an increase in serum uric acid production and oxidative stress. In this study, we investigated the nonlinear association between the UCR and long-term mortality in patients with hypertension. Data were acquired from the National Health and Nutrition Examination Survey database, and a total of 11,346 patients with hypertension were included. We explored the nonlinear link between the UCR and all-cause mortality via spline smoothing, threshold saturation, and log-likelihood ratio tests. The results were validated through a competing risk model. A nonlinear pattern emerged between the UCR and all-cause mortality in hypertensive patients, with an inflection point at 4.3. Below this point, an increased UCR was associated with a decreased mortality risk (OR = 0.80, 95% CI: 0.68-0.94, P = 0.008), whereas above this point, the risk increased (OR = 1.21, 95% CI: 1.07-1.36, P = 0.004). The competing risk model yielded similar findings for cardiovascular and chronic kidney disease-related deaths. In patients with hypertension, the UCR nonlinearly predicted all-cause mortality, with a notable inflection at 4.3. These findings suggest that the UCR is a valuable prognostic indicator for assessing long-term outcomes in patients with hypertension.

Gout and Hyperuricemia: A Narrative Review of Their Comorbidities and Clinical Implications

Gout is the most common form of inflammatory arthritis, caused by the deposition of monosodium urate crystals in the joints due to elevated serum uric acid levels. Its prevalence and associated healthcare burden have been rising in recent decades, a trend expected to continue. It is crucial to recognize that gout and hyperuricemia are not merely causes of painful joint flares, but systemic metabolic disorders linked to a broad spectrum of comorbidities such as cardiovascular diseases, chronic kidney disease, diabetes, insulin resistance, steatotic liver disease, osteoarthritis, and respiratory and eye diseases. Numerous risk factors for gout and hyperuricemia have been identified, with recent research uncovering further associations with other conditions. To optimize patient outcomes, gout and hyperuricemia must be addressed through a holistic approach that accounts for these risk factors while providing comprehensive management of related comorbidities affecting various organ systems. This review summarizes the current knowledge on the risk factors, comorbidities, and clinical implications of gout and hyperuricemia. Future research should focus on improving patient outcomes by tailoring treatments individually and addressing the underlying metabolic comorbidities of gout with multimodal treatment.

The serum uric acid to serum creatinine ratio is an independent risk factor for type 2 diabetes in community-dwelling elderly: A longitudinal analysis

BACKGROUND AND AIM

Elevated serum uric acid (SUA) levels are an important marker of metabolic disorders. However, SUA levels largely depend on renal clearance function. This study aims to investigate the relationship between renal function-normalized SUA [SUA to serum creatinine (SCr) ratio] and the risk of developing type 2 diabetes in a community-dwelling elderly population.

METHODS AND RESULTS

A retrospective cohort study was conducted on elderly, non-diabetic individuals from the Kunshan community in China, who participated in annual health check-ups between January 2018 and December 2023. The relationship between the baseline SUA/SCr ratio and the risk of type 2 diabetes was examined using Cox regression models, restricted cubic splines (RCS), and subgroup analyses. After a median follow-up of 3.88 years, 778 cases of type 2 diabetes were identified among 7671 elderly non-diabetic individuals. Adjusting for confounding variables, the baseline SUA/SCr ratio was significantly linked to type 2 diabetes risk (P < 0.001). Individuals in the highest SUA/SCr ratio quartile had a 1.323 times higher risk of developing type 2 diabetes compared to those in the lowest quartile (HR = 1.323, 95% CI 1.053-1.661, P = 0.016). RCS analysis further confirmed this positive association. Additionally, subgroup analyses suggested that this relationship was particularly pronounced in female individuals.

CONCLUSIONS

In Chinese elderly community residents, the baseline SUA/SCr ratio is linked to the risk of type 2 diabetes. Monitoring this ratio could aid in predicting and assessing the risk of type 2 diabetes.

Management of hypertension addressing hyperuricaemia: introduction of nano-based approaches

Uric acid (UA) levels in blood serum have been associated with hypertension, indicating a potential causal relationship between high serum UA levels and the progression of hypertension. Therefore, the reduction of serum UA level is considered a potential strategy for lowering and mitigating blood pressure. If an individual is at risk of developing or already manifesting elevated blood pressure, this intervention could be an integral part of a comprehensive treatment plan. By addressing hyperuricaemia, practitioners may subsidize the optimization of blood pressure regulation, which illustrates the importance of addressing UA levels as a valuable strategy within the broader context of hypertension management. In this analysis, we outlined the operational principles of effective xanthine oxidase inhibitors for the treatment of hyperuricaemia and hypertension, along with an exploration of the contribution of nanotechnology to this field.

A nonlinear correlation between the serum uric acid to creatinine ratio and the prevalence of hypertension: a large cross-sectional population-based study

OBJECTIVE

To explore the relationship between the serum uric acid to creatinine (UA/Cr) ratio and the prevalence of hypertension.

METHODS

In this cross-sectional study, we included 8571 individuals from the China Health and Nutrition Survey. Logistic regression analysis and restricted cubic spline (RCS) were used to analyze the relationship between the UA/Cr ratio and hypertension.

RESULTS

Compared with individuals without hypertension, individuals with hypertension had higher UA/Cr ratios. Multivariate logistic regression analysis showed that a higher UA/Cr ratio was closely related to a higher risk of hypertension (as a continuous variable, OR: 1.054, 95% CI: 1.014-1.095, p = 0.007; as a categorical variable, Q3 vs. Q1, OR: 1.183, 95% CI: 1.011-1.384, p = 0.035; Q4 vs. Q1, OR: 1.347, 95% CI: 1.146-1.582, p < 0.001). Subgroup analysis revealed that the correlation between the UA/Cr ratio and hypertension risk was stable in all subgroups except for the subgroup with diabetes and the subgroup with a BMI ≥ 28 kg/m2 (p < 0.05). Sensitivity analysis confirmed the robustness of the relationship between a higher UA/Cr ratio and a higher risk of hypertension (p < 0.05). The RCS showed that the UA/Cr ratio was nonlinearly related to hypertension risk. Further threshold effect showed that only a UA/Cr ratio less than 5.0 was related to hypertension risk (OR: 1.178, 95% CI: 1.086-1.278, p < 0.001), and the 2-piecewise linear regression model was superior to the 1-line linear regression model (p < 0.05).

CONCLUSION

The UA/Cr ratio was associated with the prevalence of hypertension.

Hyperuricemia and elevated uric acid/creatinine ratio are associated with stages III/IV periodontitis: a population-based cross-sectional study (NHANES 2009-2014)

OBJECTIVES

To explore the association between hyperuricemia and having periodontitis.

MATERIALS AND METHODS

A representative cross-sectional dataset of 10,158 adults was extracted from the National Health and Nutrition Examination Survey (NHANES) 2009-2014. The association between hyperuricemia (the primary exposure) and having periodontitis (outcome) were evaluated using weighted logistic regression models. Serum uric acid (UA) levels and the UA to creatinine (UA/Cr) ratio were used as secondary exposures. Their associations with the diagnosis periodontitis were analyzed using weighted logistic regression or restricted cubic spline regression.

RESULTS

The prevalence of Stages III/IV periodontitis was 47.7% among individuals with hyperuricemia and 37.4% among those without. After adjustment, individuals with hyperuricemia had 0.281 times higher odds of developing Stages III/IV periodontitis compared to those without hyperuricemia (adjusted OR = 1.286, 95% CI = 1.040 to 1.591, P = 0.024). The increased odds could be explained by a linear relationship with the serum UA/Cr ratio and a U-shaped relationship with serum UA levels. Each unit increase in the serum UA/Cr ratio was associated with 0.048 times higher odds of developing Stages III/IV periodontitis (adjusted OR = 1.048, 95% CI = 1.008 to 1.088, P = 0.021). Additionally, each 1 mg/dL increase in serum UA was associated with 0.156 times higher odds (adjusted OR = 1.156, 95% CI = 1.009 to 1.323, P = 0.038) of developing Stages III/IV periodontitis when UA levels were greater than 5.9 mg/dL, but 0.118 times lower odds when UA levels were 5.9 mg/dL or lower (adjusted OR = 0.882, 95% CI = 0.790 to 0.984, P = 0.027). Sensitivity analyses validated the robustness of the findings.

CONCLUSIONS

This study provides the first direct evidence that hyperuricemia is associated with Stages III/IV periodontitis.

CLINICAL RELEVANCE

Hyperuricemia may represent a new potential comorbidity of periodontitis, possibly contributing directly or indirectly to the disease burden in patients with periodontitis.

CLINICAL TRIAL NUMBER

Not applicable.

Asymptomatic hyperuricemia: to treat or not a threat? A clinical and evidence-based approach to the management of hyperuricemia in the context of cardiovascular diseases

Asymptomatic hyperuricemia is defined by serum uric acid levels above 6.2 mg/dl in women and 7 mg/dl in men. In the presence of monosodium urate crystal formation and articular inflammation, hyperuricemia may become symptomatic (namely nephrolithiasis and gout). Uric acid results from purine catabolism and is at the centre of a complex metabolic interplay that involves oxidative stress, inflammation, renin-angiotensin-aldosterone system (RAAS) activation and insulin resistance. Uric acid levels present a continuous relation with conditions like hypertension and chronic kidney disease (CKD) and are reported to have an impact on risk of cardiovascular events. However, whether elevated uric acid is a causal agent and thus a possible therapeutic target is still uncertain and matter of further investigation. Treating symptomatic hyperuricemia involves lowering uric acid drugs and controlling inflammation. Urate-lowering agents are well tolerated but show minimal impact on cardiovascular events in patients with gout. Use of direct-acting urate-lowering agents in asymptomatic hyperuricemia associated with cardiovascular diseases does not warrant a clear benefit, whereas addressing cardiovascular issues with guideline-recommended therapies lowers uric acid and reduces the occurrence of cardiovascular events. Regular assessment of uric acid and clinical symptoms is advised before starting and renewing a urate-lowering treatment.

Serum uric acid to eGFR ratio correlates with adverse outcomes in elderly hospitalized for acute heart failure

BACKGROUND

Serum uric acid (SUA) is a known biomarker of severity in acute heart failure (AHF), reflecting the intricate interplay between cardiovascular and metabolic dysfunction. Since SUA can increase in response to worsening kidney function, and subjects with AHF often have cardiorenal syndrome or are on diuretic therapy, we tested whether the ratio of SUA to eGFR might provide prognostic value in elderly hospitalized for AHF.

METHODS

The BOTERO-AHF Study (BOlogna study of Therapies, Epidemiology and Radiodiagnostic Outcomes in Acute Heart Failure patients) included 293 patients admitted for AHF who were consecutively enrolled from January 2020 onwards. We compared the baseline characteristics of participants who had a composite outcome (CO) (n = 203) of death or re-hospitalization for AHF within 12 months from discharge to those without CO (n = 90), and we assessed the prognostic impact of SUA/eGFR for 12-months CO.

RESULTS

SUA/eGFR was significantly higher in participants who experienced a CO within 12 months from discharge for AHF, compared to those who did not experience any CO (17.8 (16.6) vs. 13.7 (12.1) mg/dl/ml/min*100, p = 0.008). SUA/eGFR, and not SUA alone, was associated with an increase in the rate of CO (unadjusted HR 1.011, CI 95% 1.004-1.019, p = 0.003). This association lost significance in participants under treatment with xanthine oxidase inhibitors but remained significant after adjustment for multiple confounders.

CONCLUSION

The SUA/ eGFR ratio provides prognostic value in elderly patients hospitalized for AHF. Future studies may clarify if SUA/eGFR and XOI may represent novel diagnostic and therapeutic approaches for subgroups of patients with AHF.

Association between serum uric acid to serum creatinine ratio with cardiovascular and all-cause mortality in adults with hypertension

The serum uric acid to serum creatinine ratio (SUA/sCr) is a standardized index of renal function. More importance was attached to the significance of this ratio in the progression of hypertension. While the association between the prognosis of hypertension and SUA/sCr is unknown. Therefore, we aimed to prospectively examine the associations of serum uric acid to serum creatinine ratio and all-cause and CVD mortality in adults with hypertension. Participants with hypertension from NHANES 1999-2018 (n = 15,269) were included. They were stratified by 1 increment of SUA/sCr ratio and categorized into 6 groups as ≤ 4, > 4 to 5, > 5 to 6, > 6 to 7, > 7 to 8, and > 8. The reason for categorization in 6 groups was to analyze the influence of different ratios on outcomes accurately and provide more precise guidance. The sample size is large enough that even if divided into 6 groups, it does not affect the statistical power. The primary outcomes were all-cause and CVD mortality. Weighted multivariable Cox proportional hazards regression models were used to estimate hazard ratio (HRs) of mortality. Restricted cubic spline regression models were utilized to examine dose-response associations between the serum uric acid to serum creatinine ratio and all-cause and CVD mortality. Relatively comprehensive stratified analyses were conducted to confirm the accuracy and stability of the results. There were 15,269 total participants, 49.4% of whom were men, with an average age of 56.6 years. Weighted multivariable Cox proportional hazards regression models demonstrated participants in the lowest group (≤ 4) had the HRs (95% CIs) of 1.43 (1.18, 1.73) for all-cause mortality and 2.8 (1.92, 4.10) for CVD mortality when compared to the reference group. Participants in the highest group (> 8) had the HRs (95% CIs) of 0.47 (0.25, 0.89) for CVD mortality when compared to the reference group. There were progressively lower risks for all-cause and CVD mortality with the SUA/sCr ratio increased (both P trend < 0.01). The SUA/sCr ratio was (P for nonlinearity < 0.01) nonlinearly correlated with all-cause mortality, with inflection points of 6.25. In addition, the restricted cubic splines results indicated that the SUA/sCr ratio (P for nonlinearity = 0.32) showed linear and negative associations with cardiovascular mortality with inflection points of 6.54. The inverse associations between SUA/sCr ratio and all-cause mortality were consistent across all subgroups except for the subgroup of eGFR < 45 ml/min/1.73 m2 and never smokers (P trend = 0.20 and 0.13, respectively), and the inverse associations between low SUA/sCr ratio and CVD mortality were consistent across all subgroups (P trend < 0.01). Contrary to previous studies, outcomes suggest that lower SUA/sCr ratio was associated with higher risks of all-cause and CVD mortality in adults with hypertension.

Prognostic impact of hypertension grading

BACKGROUND

Most Hypertension Guidelines grade hypertension according to various cut-off values. We sought to investigate the prognostic impact of Grades 1 (140-159 and/or 90-99 mmHg), 2 (160-179 and/or 100-109 mmHg) and 3 (≥180 and/or ≥110 mmHg).

METHODS

We followed for an average of 10 years a cohort of 3,150 initially untreated hypertensive patients (mean age 50 years, 44 % women) with no previous cardiovascular disease at entry. All patients underwent diagnostic tests including 24-hour ambulatory blood pressure (BP) monitoring.

RESULTS

At entry, average clinic BP was 156/97 mmHg and average 24-hour BP was 137/87 mmHg. During follow-up, 314 patients experienced a first major cardiovascular event (composite of non-fatal myocardial infarction or stroke, cardiovascular death, or hospitalization for heart failure). Event rate was not formally dissimilar between Grade 1 and Grade 2 (0.73 vs 0.95 per 100 patient-years, respectively; p = 0.06). It was higher in Grade 3 (1.93 per 100 patient-years; p < 0.01 vs Grade 1 and Grade 2). After adjustment for a robust set of covariables, the hazard ratio was not dissimilar between Grade 1 and Grade 2 (p = 0.27), and higher in Grade 3 than in Grade 1 (p < 0.01), but the excess risk in Grade 3 was no longer significant (hazard ratio: 1.25, 95 % CI 0.87-1.78; p = 0.22) after adjustment for 24-hour ambulatory systolic BP.

CONCLUSIONS

We were unable to find a significant difference in the relative hazard of cardiovascular events tied to hypertension Grades 1 and 2. Conversely, Grade 3 (clinic BP ≥180/110 mmHg) portends a higher cardiovascular risk, which is associated with higher levels of 24-hour ambulatory BP.

Serum Uric Acid, Hypertriglyceridemia, and Carotid Plaques: A Sub-Analysis of the URic Acid Right for Heart Health (URRAH) Study

High levels of serum uric acid (SUA) and triglycerides (TG) might promote high-cardiovascular-risk phenotypes, including subclinical atherosclerosis. An interaction between plaques xanthine oxidase (XO) expression, SUA, and HDL-C has been recently postulated. Subjects from the URic acid Right for heArt Health (URRAH) study with carotid ultrasound and without previous cardiovascular diseases (CVD) (n = 6209), followed over 20 years, were included in the analysis. Hypertriglyceridemia (hTG) was defined as TG ≥ 150 mg/dL. Higher levels of SUA (hSUA) were defined as ≥5.6 mg/dL in men and 5.1 mg/dL in women. A carotid plaque was identified in 1742 subjects (28%). SUA and TG predicted carotid plaque (HR 1.09 [1.04-1.27], p < 0.001 and HR 1.25 [1.09-1.45], p < 0.001) in the whole population, independently of age, sex, diabetes, systolic blood pressure, HDL and LDL cholesterol and treatment. Four different groups were identified (normal SUA and TG, hSUA and normal TG, normal SUA and hTG, hSUA and hTG). The prevalence of plaque was progressively greater in subjects with normal SUA and TG (23%), hSUA and normal TG (31%), normal SUA and hTG (34%), and hSUA and hTG (38%) (Chi-square, 0.0001). Logistic regression analysis showed that hSUA and normal TG [HR 1.159 (1.002 to 1.341); p = 0.001], normal SUA and hTG [HR 1.305 (1.057 to 1.611); p = 0.001], and the combination of hUA and hTG [HR 1.539 (1.274 to 1.859); p = 0.001] were associated with a higher risk of plaque. Our findings demonstrate that SUA is independently associated with the presence of carotid plaque and suggest that the combination of hyperuricemia and hypertriglyceridemia is a stronger determinant of carotid plaque than hSUA or hTG taken as single risk factors. The association between SUA and CVD events may be explained in part by a direct association of UA with carotid plaques.

Progress of uric acid in cardiovascular disease

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

Does Serum Uric Acid to Creatinine Ratio Predict Mortality Risk in Patients With Heart Failure?

BACKGROUND

Previous studies have established a positive correlation between serum uric acid to creatinine (SUA/Cr) ratio and cardiovascular disease, but the relationship between SUA/Cr ratio and the prognosis of heart failure (HF) remains unknown. This study investigated the potential of SUA/Cr ratio as a prognostic predictor for patients with HF.

METHODS

This single-center prospective cohort study enrolled 2,122 patients with HF between March 2013 and June 2017. All patients were divided into 3 groups according to SUA/Cr ratio tertiles and were followed up with until December 31, 2022. The association between SUA/Cr ratio and the prognosis of HF was assessed using the Cox proportional hazards model.

RESULTS

The mean (SD) age and mean (SD) SUA/Cr ratio of the study cohort (66% male) were 59.3 (14.7) years and 4.71 (2.09), respectively. During a median follow-up period of 15 months (range, 11-26 months), 390 end-point events were observed. Prognosis analysis revealed that a high SUA/Cr ratio was associated with an increased mortality risk of HF (hazard ratio, 1.62 [95% CI, 1.26-2.09]; P < .001) compared with the SUA/Cr ratio in the lowest tertile. After adjusting for covariates, the hazard ratio for mortality risk of HF was 1.71 (95% CI, 1.23-2.37; P = .001). Subgroup analysis showed that mortality risk increased in direct proportion with the SUA/Cr ratio in female patients, patients with a history of hypertension and β-blocker use, and patients with UA levels below 428 μmol/L and creatinine levels less than 97 mg/dL. Stratification by age; by history of diabetes, hyperlipidemia, and smoking; and by level of fasting plasma glucose, however, had no obvious effect on the association between SUA/Cr ratio and HF prognosis. Patients with higher SUA/Cr ratios had reduced left ventricular ejection fraction and increased left ventricular end-diastolic diameter.

CONCLUSION

A high SUA/Cr ratio was an independent risk factor for the mortality risk of HF.

J-shaped association of serum uric acid concentrations with all-cause mortality in individuals with osteoarthritis: A prospective cohort study

OBJECTIVE

The purpose of this study was to explore the relationship between serum uric acid (SUA) concentrations and all-cause mortality in individuals with osteoarthritis (OA).

METHODS

All participant data were retrieved from the National Health and Nutrition Examination Survey database. A total of 4671 participants (age range: 20 to 85 years old), including 2988 females and 1683 males, were included in this study. The determination of death outcome was based on the National Death Index (up to December 31, 2019). We explored the nonlinear relationship between SUA concentrations and all-cause mortality in OA patients by establishing a Cox proportional risk model and a two-segment Cox proportional risk model and ran an interaction test to identify the high-risk population for all-cause mortality.

RESULTS

During 30,645 person-years of follow-up, the number of all-cause deaths for females and males was 736 and 516, respectively. After multivariate adjustment, we found a nonlinear relationship between SUA concentrations and all-cause mortality in both females and males with OA. In addition, we found a J-shaped relationship between SUA concentrations and all-cause mortality. The SUA concentration thresholds for all-cause mortality of females and males were stable at 5.6mg/dl and 6.2mg/dl, respectively. Compared with SUA concentrations below the inflection point, the all-cause mortality risk at higher SUA concentrations in females and males with OA increased by 20% (hazard ratio [HR]: 1.2, 95% confidence interval [CI]: 1.1 to 1.2) and 25% (HR: 1.2, 95% CI: 1.12 to 1.39), respectively.

CONCLUSIONS

There is a nonlinear relationship between SUA concentrations and all-cause mortality in the American OA population (J-shaped association). The all-cause mortality thresholds for SUA concentrations in females and males are 5.6mg/dl and 6.2mg/dl, respectively.

Uric acid levels and heart failure: A mendelian randomization study

BACKGROUND AND AIMS

Uric acid, the end-product of purine metabolism within the human body, has been the subject of studies exploring its potential association with cardiovascular and cerebrovascular diseases. However, the precise relationship between uric acid levels and heart failure remains elusive.

METHODS AND RESULTS

In this particular study, aggregated data from genome-wide association studies on uric acid and heart failure were utilized to perform a two-sample Mendelian randomization (MR) analysis utilizing R software. The aim was to uncover any causal link between these variables. The primary outcome was assessed using inverse variance weighted (IVW) methodology, while sensitivity analyses employed MR-Egger, weighted median (WME), and MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) techniques. IVW results revealed a possible causal relationship between elevated uric acid levels and an increased risk of heart failure (OR: 1.09, 95 % CI: 1.01-1.17, P < 0.05). Encouragingly, the directions provided by MR-Egger and WME aligned with IVW findings, and no anomalies were detected in the remaining sensitivity analyses.

CONCLUSION

These outcomes indicate the stability of the results of the study, thereby suggesting that heightened uric acid levels may contribute to an augmented risk of heart failure.

Hyperuricaemia-associated all-cause mortality risk effect is increased by non-impaired kidney function - Is renal hyperuricaemia less dangerous?

BACKGROUND

Both hyperuricaemia and chronic kidney disease are known mortality risk factors. This study examined the modifying effect of renal function on hyperuricaemia-associated mortality risk, which is an issue that has not been studied before.

METHODS

Data on levels of serum uric acid (SUA), creatinine, cystatin C and other variables of persons aged 52-76 years were collected. Persons with SUA >410 μmol/L (75th percentile) were classified as clearly hyperuricaemic and persons with eGFR of ≤67 ml/min (25th percentile) as having reduced kidney function.

RESULTS

Reduced kidney function was associated with higher mortality in both SUA groups. When compared to individuals with SUA ≤410 μmol/L and eGFR >67 ml/min the hazard ratio (HR) for all-cause mortality was 1.53 (95 % CI: 1.26-1.84) in clearly hyperuricaemic persons with reduced kidney function, 1.26 (95 % CI: 1.02-1.55) in clearly hyperuricaemic persons with eGFR of >67 ml/min and 1.15 (95 % CI: 0.96-1.39) in persons with SUA ≤410 μmol/L and reduced kidney function. The HR for hyperuricaemia-related premature death was lowest in individuals with reduced eGFR, and it rose strikingly as the eGFR increased above 90 ml/min.

CONCLUSIONS

Reduced kidney function is a risk factor for mortality both in individuals with normal and elevated SUA. The hyperuricaemia-associated mortality risk is remarkably higher in individuals with normal kidney function than in individuals with reduced kidney function. Presumably overproduction of uric acid (metabolic hyperuricaemia) is a separate and more deleterious entity than hyperuricaemia resulting from reduced renal excretion of uric acid (renal hyperuricaemia).

TG: A Mediator of the Relationship of Serum Uric Acid to Creatinine Ratio and Nonalcoholic Fatty Liver Disease in Non-Obese Patients with Type 2 Diabetes

Background

The study estimated the association between NAFLD and SUA/Cr in Chinese non-obese patients with type 2 diabetes mellitus (T2DM) and also investigated mediating effect of TG.

Methods

All patients were divided into NAFLD group (n = 420) and non-NAFLD group (n = 347). The differences of biochemical indicators between the two groups were compared. The link between SUA/Cr and other parameters was checked through Spearman correlation analysis. Differences in the incidence rate of NAFLD between SUA/Cr and TG 3 tertile subgroups were tested by chi-squared. To explore the independent influence of SUA/Cr and TG on NAFLD, logistic regression was performed. The predictive value of SUA/Cr and SUA/Cr combined with BMI for NAFLD was analyzed using ROC curves. In addition, to confirm whether TG has a mediating effect on the link of SUA/Cr and NAFLD, we conducted a mediating analysis.

Results

NAFLD group had higher SUA/Cr values than individuals without NAFLD (P < 0.01). SUA/Cr was linked with TC and TG (r = 0.081, 0.215 respectively). NAFLD prevalence increased progressively from quartile 1 to quartile 3 of SUA/Cr (44% vs 57% vs 62%). Prevalence of NAFLD increased from quartile 1 to quartile 3 of TG (35.8% vs 58.7% vs 69.9%). Analysis of the logistic regression revealed that SUA/Cr and TG were statistically linked with NAFLD. The ROC curve pointed out that the area under the curve (AUC), sensitivity and specificity of SUA/Cr were 0.59, 0.629 and 0.522, respectively. The AUC, sensitivity and specificity for SUA/Cr combined with BMI were 0.719, 0.644 and 0.677, separately. The mediation analysis showed a statistically direct effect of SUA/Cr on NAFLD (β=0.148, 95% CI: 0.0393, 0.2585). The function of SUA/Cr on NAFLD partially mediated by TG (β=0.1571, 95% CI: 0.0704, 0.2869).

Conclusion

SUA/Cr was significantly associated with NAFLD in non-obese T2DM patients, and TG partially mediated this association. SUA/Cr can be applied to predict for NAFLD.

The association between serum uric acid / serum creatinine ratio and in-hospital outcomes in elderly patients with acute myocardial infarction

BACKGROUND

The role of Serum uric acid (SUA) in acute myocardial infarction (AMI) was controversial, which might be influenced by the renal clearance function of the patients. The present study aimed to explore the association between serum uric acid to serum creatinine ratio (SUA/Scr), reflecting a net production of SUA, and the in-hospital outcomes of elderly patients with AMI.

METHODS

In this retrospective study, a total of 330 elderly AMI patients (≥ 75 years) were enrolled. Data of SUA and Scr on admission were collected to calculate SUA/Scr ratio. Logistic regression analysis and receiver-operating curves were performed to assess the association between SUA/Scr ratio and in-hospital major adverse cardiovascular events (MACEs) and all-cause death.

RESULTS

Among the 330 patients, 68 patients had MACEs and 44 patients died. Patients with MACEs or died had lower SUA/Scr values compared with those without MACEs or survival (P < 0.05). Univariate logistic analysis showed that a lower value of SUA/Scr (< 3.45) was significantly associated with in-hospital MACEs (odd ratios (OR): 2.359, 95% confidential interval (CI): 1.369-4.065, P = 0.002) and death (OR: 2.424, 95% CI: 1.275-4.608, P = 0.007). After correcting for confounding factors, a lower SUA/Scr value was still independently associated with in-hospital MACEs (OR: 2.144, 95% CI: 1.169-3.934, P = 0.014) and death (OR: 2.125, 95% CI: 1.050-4.302, P = 0.036). Subgroup analysis showed that the association between a lower SUA/Scr ratio and increased risk of in-hospital outcomes could observed only in males (OR: 2.511, 95%CI: 1.211-5.207, P = 0.013 for MACEs; OR: 2.730, 95% CI: 1.146-6.502, P = 0.023 for death).

CONCLUSIONS

A lower SUA/Scr ratio was associated with an increased risk of in-hospital adverse events in elderly patients with AMI, especially in males, which maybe a marker of poor outcomes for elderly AMI patients.

STRUGGLE FOR. Italian-Polish-Spanish-Uzbek-Vietnamese Expert Forum Position Paper 2023 for better control of classical modifiable risk factors in clinical practice

The progress in pharmacotherapy that has been made in recent years, including the introduction of very effective and safe lipid-lowering and antihypertensive drugs, has not yet translated into the expected universal control of blood pressure, lipid disorders and diabetes. In the STRUGGLE FOR Italian- -Polish-Spanish-Uzbek-Vietnamese Expert Forum Position Paper 2023, experts from five countries recounted several points about the paradigms of cardiological and cardiometabolic care for better control of classical modifiable risk factors in the year 2023. It is believed herein, that the need to intensify treatment, actively search for patients with cardiovascular risk factors, especially with arterial hypertension, hypercholesterolemia and diabetes, should go hand in hand with the implementation of the latest therapy, based on single pill combinations including proven, effective antihypertensive, lipid-lowering and antidiabetic molecules, many of which are listed in the present document. There is a need to use both new technological concepts, completely new drugs, as well as novel treatment concepts such as metabolic treatment in coronary artery disease, try to intensify the fight against smoking in every way, including the available range of drugs and procedures reducing the harm. This approach will provide substantially better control of the underlying cardiovascular risk factors in countries as varied as Italy, Poland, Spain, Uzbekistan and Vietnam.

Higher ratio of serum uric acid to serum creatinine (SUA/SCr) increases the risk of metabolic unhealthy phenotype

BACKGROUND AND AIM

It is very important to understand which factors play roles in switching from a healthy to an unhealthy metabolism. It is unclear if SUA/SCr is an independent risk factor for metabolic unhealthy phenotype. We examined whether SUA/SCr is associated with an increased risk for metabolic unhealthy phenotype in the Chinese population.

METHODS AND RESULTS

As many as 3158 subjects aged 25-75 years who had a metabolic healthy phenotype at baseline were included in the retrospective cohort study. They were assigned to four groups based on the quartile of SUA/SCr. We compared the demographic and clinical characteristics among the four groups. The correlation between SUA/SCr and the risk of metabolic unhealthy phenotype in the overall population and stratified by subgroups was examined by logistic regression analyses. Greater SUA/SCr values were correlated with greater BMI, systolic and diastolic BP, TC, TG, RBC, WBC, HB, ALT, SUA and eGFR. During the two-year follow-up, 632 of the study subjects (20.01%) developed new-onset metabolic unhealthy phenotype from the total of 3158 study subjects. A statistically significant increase in the rates of metabolic unhealthy phenotype was observed with increasing SUA/SCr levels within each group. After multivariate adjustment, the adjusted ORs and 95% CIs were 1.44 (1.03-2.00) and 2.11 (1.52-2.94) in the Q3 group and Q4 group, respectively.

CONCLUSION

SUA/SCr was positively related to the risk of metabolic unhealthy phenotype in the Chinese subjects, suggesting the potential of SUA/SCr to serve as an independent risk predictor in the development of metabolic unhealthy phenotype.

The Results of the URRAH (Uric Acid Right for Heart Health) Project: A Focus on Hyperuricemia in Relation to Cardiovascular and Kidney Disease and its Role in Metabolic Dysregulation

The relationship between Serum Uric Acid (UA) and Cardiovascular (CV) diseases has already been extensively evaluated, and it was found to be an independent predictor of all-cause and cardiovascular mortality but also acute coronary syndrome, stroke and heart failure. Similarly, also many papers have been published on the association between UA and kidney function, while less is known on the role of UA in metabolic derangement and, particularly, in metabolic syndrome. Despite the substantial number of publications on the topic, there are still some elements of doubt: (1) the better cut-off to be used to refine CV risk (also called CV cut-off); (2) the needing for a correction of UA values for kidney function; and (3) the better definition of its role in metabolic syndrome: is UA simply a marker, a bystander or a key pathological element of metabolic dysregulation?. The Uric acid Right for heArt Health (URRAH) project was designed by the Working Group on uric acid and CV risk of the Italian Society of Hypertension to answer the first question. After the first papers that individuates specific cut-off for different CV disease, subsequent articles have been published responding to the other relevant questions. This review will summarise most of the results obtained so far from the URRAH research project.

Uric acid significantly correlates with the presence of low-voltage areas at the endocardial mapping in patients with non-valvular atrial fibrillation

BACKGROUND AND AIMS

Interest in the role of atrial substrate in maintaining Atrial Fibrillation (AF) is growing. Fibrosis is the culprit in the electrical derangement of the myocytes. Many cardiovascular risk factors are known to be linked to atrial scarring; among them Uric Acid (UA) is emerging. The purpose of our study is to find whether UA is associated with Left Atrium (LA) with pathological substrate.

METHODS AND RESULTS

81 patients who underwent radiofrequency transcatheter ablation for nonvalvular AF at the cardiological department of the Niguarda Hospital were enrolled in an observational, cross-sectional, single-center study. UA levels were analysed before the procedure. High density electroanatomic mapping of the LA was performed and patients were divided according to the presence or not of areas of pathological substrate (bipolar voltage <0.5 mV in sinus rhythm). 19 patients showed a LA with pathological substrate. These subjects showed a significant higher prevalence of persistent phenotype of AF (84.2 vs. 25.8%, p < 0.001). UA levels were significantly higher in the group of patients with LA with pathological substrate (6.8 ± 1.9 vs 5.3 ± 1.4 mg/dL, p < 0.001) as well as the prevalence of hyperuricemia (26.5 vs. 6.5%, p = 0.021). The association between uric acid LA with pathological substrate remains significant even after correction for confounding factors (age, left ventricular dysfunction, valvular disease, arrythmia phenotype and furosemide use) and also when the ratio UA/creatinine was evaluated.

CONCLUSIONS

In a population of patients who underwent AF ablation, higher UA levels were significantly associated with pathological LA substrate at electro-anatomical mapping.

Serum uric acid to creatinine ratio and metabolic syndrome in middle-aged and elderly population: Based on the 2015 CHARLS

BACKGROUND AND AIMS

Serum uric acid to creatinine ratio (SUA/Cr) may be associated with metabolic syndrome (MS). Here, we investigated the correlation between SUA/Cr and MS in Chinese residents aged ≥ 45 years.

METHODS AND RESULTS

Data were obtained from the 2015 China Health and Retirement Longitudinal Study (CHARLS) database. MS was diagnosed using the Chinese Diabetes Society 2017 criteria. We grouped the population according to SUA/Cr quartiles and compared the index differences between groups. We used spearman correlation analysis and binary logistic regression. The possible dose-response association of SUA/Cr with MS were analyzed using restricted cubic spline model. Of 12,946 included participants, 3370 (26.0%) had MS, and 1900 (56.4%) were female. After adjusting for multiple confounders, binary logistic regression analysis showed that compared with Quartile 1, the odds ratio (95% confidence interval) of the MS risk was 1.29 (1.09-1.52), 1.47 (1.25-1.74), and 1.80 (1.53-2.12) in Quartiles 2, 3, and 4, respectively. The restricted cubic spline model indicated a significant nonlinear dose-response association (P_overall < 0.001, P_{non-linearity} = 0.029) between SUA/Cr and strength of MS prevalence association; MS risk began increasing when SUA/Cr > 6.22.

CONCLUSIONS

A significant positive correlation existed between SUA/Cr and MS risk in Chinese individuals aged ≥ 45 years, which may be a new predictive marker for MS risk.

Serum Uric Acid Levels Are Associated with the Echogenic Features of Carotid Plaque Vulnerability in Elderly Patients with Atherosclerotic Disease

Uric acid is a marker of inflammation and a risk factor for atherosclerosis that has been suggested to play a role in carotid plaque instability. Reduced atherosclerotic plaque echogenicity at ultrasound examination is associated with alarming histopathological features and inflammation. In this study, we investigated the relationship between serum uric acid (SUA) levels and echogenic patterns of plaque instability in elderly subjects with carotid atherosclerosis. Since uric acid metabolism largely depends on renal function, SUA levels were indexed for serum creatinine levels (SUA/SCr). We enrolled 108 patients aged 65 years or more (72.7 ± 5.9 years; 50 females and 58 males) who underwent carotid duplex ultrasound to evaluate plaque echogenicity by greyscale median (GSM). The regression analysis demonstrated a significant inverse association between the GSM and the SUA/SCr ratio (β: -0.567; 95% CI -0.751 to -0.384 and p < 0.0001). Stepwise multivariate regression showed that the SUA/SCr ratio explained 30.3% of GSM variability (β: -0.600; 95% CI -0.777/-0.424, p < 0.0001, and semi-partial correlation 0.303). After a mean period of 3.5 ± 0.5 years, 48 patients were reevaluated according to the same baseline study protocol. The regression analysis demonstrated a still significant inverse association between the GSM and the SUA/SCr ratio (β: -0.462; 95% CI -0.745 to -0.178 and p = 0.002). Stepwise multivariate regression showed that the SUA/SCr ratio explained 28.0% of GSM variability (coefficient -0.584, 95% CI -0.848/-0.319, p < 0.0001, and semi-partial R² 0.280). In conclusion, this study demonstrates that SUA levels indexed for serum creatinine are associated with the echogenic features of carotid plaque vulnerability in elderly patients with atherosclerotic disease. These data could suggest an influential role for uric acid metabolism in carotid plaque biology.

Gout and hyperuricaemia: modifiable cardiovascular risk factors?

Gout and hyperuricaemia are two clinical situations associated with an elevated risk of developing cardiovascular (heart failure, myocardial infarction, stroke) and metabolic and renal complications. One reason is probably related to the fact that the prevalence of hyperuricaemia and gout is high in clinical situations, which themselves involve a high cardiovascular risk, such as hypertension, diabetes, chronic kidney disease or obesity. However, recent studies suggest that hyperuricaemia may promote cardiovascular complications independently of other cardiovascular risk factors, by inducing chronic inflammation, oxidative stress, and endothelial dysfunction. The questions that arise today concern primarily the treatment of asymptomatic hyperuricaemia. Should it be treated to decrease the patients' cardiovascular risk and if so, starting from which level and towards which target? There are now several pieces of evidence indicating that this might be useful, but data from large studies are not unanimous. This review will discuss this issue as well as new well-tolerated treatments, such as febuxostat or SGLT2 inhibitors, which lower uric acid levels, prevent gout and lower the risk of cardio-renal events.

Purine Metabolism Dysfunctions: Experimental Methods of Detection and Diagnostic Potential

Purines, such as adenine and guanine, perform several important functions in the cell. They are found in nucleic acids; are structural components of some coenzymes, including NADH and coenzyme A; and have a crucial role in the modulation of energy metabolism and signal transduction. Moreover, purines have been shown to play an important role in the physiology of platelets, muscles, and neurotransmission. All cells require a balanced number of purines for growth, proliferation, and survival. Under physiological conditions, enzymes involved in purines metabolism maintain a balanced ratio between their synthesis and degradation in the cell. In humans, the final product of purine catabolism is uric acid, while most other mammals possess the enzyme uricase that converts uric acid to allantoin, which can be easily eliminated with urine. During the last decades, hyperuricemia has been associated with a number of human extra-articular diseases (in particular, the cardiovascular ones) and their clinical severity. In this review, we go through the methods of investigation of purine metabolism dysfunctions, looking at the functionality of xanthine oxidoreductase and the formation of catabolites in urine and saliva. Finally, we discuss how these molecules can be used as markers of oxidative stress.

Serum Uric Acid Predicts All-Cause and Cardiovascular Mortality Independently of Hypertriglyceridemia in Cardiometabolic Patients without Established CV Disease: A Sub-Analysis of the URic acid Right for heArt Health (URRAH) Study

High serum uric acid (SUA) and triglyceride (TG) levels might promote high-cardiovascular risk phenotypes across the cardiometabolic spectrum. However, SUA predictive power in the presence of normal and high TG levels has never been investigated. We included 8124 patients from the URic acid Right for heArt Health (URRAH) study cohort who were followed for over 20 years and had no established cardiovascular disease or uncontrolled metabolic disease. All-cause mortality (ACM) and cardiovascular mortality (CVM) were explored by the Kaplan-Meier estimator and Cox multivariable regression, adopting recently defined SUA cut-offs for ACM (≥4.7 mg/dL) and CVM (≥5.6 mg/dL). Exploratory analysis across cardiometabolic subgroups and a sensitivity analysis using SUA/serum creatinine were performed as validation. SUA predicted ACM (HR 1.25 [1.12-1.40], p < 0.001) and CVM (1.31 [1.11-1.74], p < 0.001) in the whole study population, and according to TG strata: ACM in normotriglyceridemia (HR 1.26 [1.12-1.43], p < 0.001) and hypertriglyceridemia (1.31 [1.02-1.68], p = 0.033), and CVM in normotriglyceridemia (HR 1.46 [1.23-1.73], p < 0.001) and hypertriglyceridemia (HR 1.31 [0.99-1.64], p = 0.060). Exploratory and sensitivity analyses confirmed our findings, suggesting a substantial role of SUA in normotriglyceridemia and hypertriglyceridemia. In conclusion, we report that SUA can predict ACM and CVM in cardiometabolic patients without established cardiovascular disease, independent of TG levels.