Elevated Serum Uric Acid Increases the Risk of Ischemic Stroke Recurrence and Its Inflammatory Mechanism in Older Adults

Association of serum uric acid to serum creatinine ratio with 1-year stroke outcomes in patients with acute ischemic stroke: A multicenter observational cohort study

BACKGROUND AND PURPOSE

Considering the reliance of serum uric acid (SUA) levels on renal clearance function, its role in stroke outcomes remains controversial. This study investigated the association of renal function-normalized SUA (SUA to serum creatinine ratio, SUA/SCr), a novel renal function index, with the 1-year outcomes in patients with acute ischemic stroke (AIS).

METHODS

This is a prospective, multicenter observational study. Renal function-normalized SUA levels were determined by calculating the ratio of SUA to SCr. One-year outcomes included stroke recurrence, all-cause mortality, and poor prognosis. Multivariable Cox regression analyses and restriction cubic splines for curve fitting were used to evaluate SUA/SCr's association with 1-year stroke outcomes.

RESULTS

Among 2294 enrolled patients, after adjustment for potential confounders, multivariable Cox regression analyses showed that each one-unit increase in SUA/SCr corresponded to a 19% decrease in 1-year stroke recurrence in patients with AIS. SUA/SCr was analyzed as a continuous variable and categorized into quartiles (Q1-Q4). Compared with the Q1 reference group, Q2, Q3, and Q4 showed significantly lower 1-year stroke recurrence risks. The trend test indicated significant differences in the 1-year stroke recurrence trend from Q1 to Q4. In these patients, SUA/SCr did not show a significant association with poor prognosis or all-cause mortality. Curve fitting revealed SUA/SCr had a negative but nonlinear association with 1-year stroke recurrence.

CONCLUSIONS

In patients with AIS, low SUA/SCr may be an independent risk factor for 1-year stroke recurrence. Changes in SUA/SCr had no significant impact on 1-year poor prognosis and all-cause mortality.

Relationship between uric acid to albumin ratio and saphenous vein graft disease in patients with coronary artery bypass graft

OBJECTIVE

Saphenous vein graft disease (SVGD) remains a challenging issue for patients with coronary artery bypass grafting (CABG). It is associated with poor outcomes and atherosclerosis is the major cause of SVGD. Uric acid to albumin ratio (UAR) is a new marker which associated with cardiovascular mortality. We aim to evaluate the relationship between the SVGD and UAR.

METHODS

We retrospectively enrolled 237 patients who underwent elective coronary angiography (CAG) for stable angina or positive stress test results >1 year after CABG. The patients were divided into two groups; SVGD (+) patients and SVGD (-) patients. The SVGD was defined as presence of at least 50% stenosis in at least 1 SVG.

RESULTS

UAR were significantly higher in the SVGD (+) group ( P  < 0.001). Similarly, Hs-CRP, white blood cell count, and neutrophil count were significantly higher in SVGD (+) group ( P  = 0.03, P  = 0.027 P  = 0.01, respectively). In multivariate logistic regression analysis, time interval after CABG [OR = 1.161, 95% confidence interval (CI) 1.078-1.250; P  < 0.001] and UAR (OR = 2.691, 95% CI 1.121-6.459; P  < 0.001) were found to be independent predictors of SVGD.

CONCLUSION

Our results suggested that UAR could be a simple and available marker to predict SVGD in patients with CABG who underwent elective percutaneous coronary intervention.

Serum uric acid: an independent risk factor for cardiovascular disease in Pakistani Punjabi patients

BACKGROUND

It is well-known that serum uric acid (SUA) can increase the risk of hypertension, diabetes, obesity and dyslipidemia. However, its independent association with the risk of cardiovascular diseases (CVD) is controversial particularly in different populations. Hence, this study was aimed to assess an independent association of SUA with CVD risk in a Punjabi Pakistani cohort.

METHODS

This is a retrospective observational study in which 502 human subjects having CVD, hypertension and/or diabetes were grouped based on SUA levels as normouricemia (n = 266) and hyperuricemia (n = 236). Role of SUA was assessed in increasing the risk of CVD independent of other key confounding factors (i.e. age, gender, dyslipidemia, hypertension, diabetes, dietary and life-style habits). All clinical and biochemical data were analyzed in SPSS (ver. 20).

RESULTS

Subjects aged 55 ± 13 years were of both genders (males: 52%). SUA levels were significantly different among clinical subtypes of CVD [i.e. acute coronary syndrome (ACS), myocardial infarction (MI) and heart failure (HF)]. Spearman correlation showed a significantly positive association between CVD and SUA (rho = 0.149, p < 0.001). Multivariate logistic regression of SUA quartiles showed that hyperuricemia is associated with CVD [3rd quartile: OR: 1.78 (CI: 1.28-2.48), p = 0.001 and 4th quartile: OR: 2.37 (CI: 1.72-3.27), p < 0.001]. Moreover, this association remained significant even after adjusting for confounding factors.

CONCLUSION

This study showed that SUA is positively associated with CVD, thus it can act as an independent risk factor for CVD.

Association of serum uric acid levels with risk of epilepsy: A national population-based study

BACKGROUND

Uric acid (UA) serves as a crucial endogenous antioxidant in the body, offering protection against oxidative stress, whichmaycontributetoepilepsypathogenesis. The association between serum UA levels and epilepsy remains uncertain. This study aimed to examine the potential connections between serum UA levels and epilepsy in US adults.

METHODS

Utilizing data from the National Health and Nutrition Examination Survey (NHANES) 2013-2018, a cross-sectional analysis was conducted. Weighted logistic regression analyses were employed to assess the potential link between serum UA levels and the risk of epilepsy. Additionally, sensitivity analyses were conducted to evaluate the reliability of the results.

RESULTS

We included 15,373 participants, of whom 136 (0.79 %) had epilepsy. Following adjustment for multiple variables, participants with serum UA levels <4.1 mg/dl had an odds ratio of 2.24 (95 % CI: 1.12-4.47, P = 0.023) for epilepsy compared to those with serum UA levels of 5.8-6.5 mg/dl. The results of the sensitivity analyses corroborated the initial findings.

CONCLUSIONS

Our study revealed a significant association between lower serum UA levels and heightened risks of epilepsy, suggesting that low UA levels may serve as an independent risk factor for epilepsy. A marginal increase in UA levels within the normal range may act as a protective factor against epilepsy.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Dual effects of serum urate on stroke risk and prognosis: insights from Mendelian randomization

Background

To investigate the causal associations of serum urate (SUA) with stroke risk and prognosis using Mendelian randomization (MR) and the potential mediating role of stroke risk factors in the causal pathways.

Methods

We used the random-effects inverse variance weighting (IVW) as our primary method. We initially performed two-sample univariable MR (UVMR) to identify the causal associations of SUA (n = 437,354) with any stroke (AS, FinnGen: n = 311,635; MEGASTROKE: n = 446,696), ischemic stroke (IS, FinnGen: n = 212,774; MEGASTROKE: n = 440,328), intracranial hemorrhage (ICH, FinnGen: n = 343,663; ISGC: n = 3,026), functional outcome after ischemic stroke at 90d (n = 4,363), and motor recovery within 24 months after stroke (n = 488), and then multivariable MR (MVMR) to estimate the direct causal effects of SUA on these outcomes, adjusting for potential confounders. Finally, we further conducted a two-step MR to investigate the potential mediating role of body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), and estimated glomerular filtration rate (eGFR) in the identified causal pathways.

Results

Genetically predicted elevated SUA levels were significantly associated with increased risk of AS (meta-analysis: OR = 1.09, 95% CI [1.04-1.13], p = 3.69e-05) and IS (meta-analysis: OR = 1.10, 95% CI [1.01-1.19], p = 0.021) and with improved poor functional outcome after ischemic stroke at 90d (OR = 0.81, 95% CI [0.72-0.90], p = 1.79e-04) and motor recovery within 24 months after stroke (OR = 1.42, 95% CI [1.23-1.64], p = 2.15e-06). In MVMR, SBP and DBP significantly attenuated the causal effects of SUA on AS, IS, and functional outcome after ischemic stroke at 90d and motor recovery within 24 months after stroke. Further mediation analyses showed that SBP mediated 52.4 and 34.5% of the effects of SUA on AS and IS, while DBP mediated 28.5 and 23.4% of the causal effects, respectively.

Conclusion

This study supports the dual role of genetically predicted SUA in increasing stroke risk, especially ischemic stroke risk, and in improving functional outcome and motor recovery. SBP and DBP are key mediators lying on the causal pathways of SUA with AS and IS.

Relationship between uric acid to albumin ratio and in-stent restenosis in patients with coronary artery disease undergoing drug-eluting stenting

BACKGROUND

In-stent restenosis (ISR) in patients undergoing percutaneous coronary intervention (PCI) to treat coronary artery disease (CAD) is an urgent issue in clinical practice. Recent studies have highlighted uric acid-albumin ratio (UAR) as a new marker for evaluating inflammation and oxidative stress, capable of predicting cardiovascular ailments. We aimed to examine the correlation between UAR levels and ISR in patients who underwent drug-eluting stent (DES) implantation.

METHODS

We included 503 patients with CAD who underwent initial DES implantation and angiography during the follow-up period. Based on coronary angiographic findings, the patients were categorized into ISR (n = 73) and non-ISR groups (n = 430). Before angiography, laboratory parameters were measured for all enrolled patients. To ascertain the influential factors linked to ISR, multivariate logistic regression analysis was performed. The predictive capability of UAR in determining ISR was assessed using receiver operating characteristic (ROC) curve analysis. Statistical significance was set at P  < 0.05.

RESULTS

Multivariate logistic regression analysis revealed that diabetes mellitus, stent length, UAR, albumin levels, and C-reactive protein levels independently predicted ISR. ROC curve analysis revealed that UAR had an area under the curve of 0.767 (95% CI: 0.709 - 0.826) for predicting ISR and demonstrated that UAR outperformed the individual predictive abilities of uric acid and albumin for ISR.

CONCLUSION

UAR was associated with ISR in patients with CAD undergoing PCI with DES implantation. Moreover, ROC curve analysis demonstrated that UAR exhibited superior predictive accuracy for ISR compared with evaluating uric acid and albumin levels separately.

Scientific Landscape of Oxidative Stress in Stroke: From a Bibliometric Analysis to an in-Depth Review

Stroke is an acute cerebrovascular disease resulting from either obstruction or rupture of a blood vessel in the brain. Oxidative stress (OS), referred to a status where cellular oxidative capacities overwhelm antioxidative defenses, is involved in the pathophysiology of stroke. The bibliometric analysis and in-depth review aim to depict the research trend of OS in stroke. Relevant scientific publications were acquired from the Web of Science Core Collection database. Scientific landscape of OS in stroke was illustrated by general quantitative trend, impactful journals, and co-authorship of various academic units (i.e., countries/regions, organizations, and authors). Furthermore, theme analysis predicting the hot research issues and frontiers was performed. 15,826 documents regarding OS in stroke were obtained over a time span of more than 20 years from 1992 to 2021. The overall tendency of publication counts was continuously on the rise. Bibliometric analysis indicated China and the United States were predominant in this study field, as reflected by their high publication counts and intensive collaboration with other countries. Current key research areas of OS in stroke may lie in the investigation of neuroinflammation, and interaction among multiple cell death mechanisms including apoptosis, autophagy, and ferroptosis to search for effective treatments. Moreover, another hot topic could be the association between air pollution and stroke, and its underlying mechanisms. As the exploration of OS in stroke is speculated to be a continuous hot spot in the future, this article may be helpful for researchers to conduct future studies with the understanding of influential academic forces and research highlights.

Serum uric acid and prognosis in acute ischemic stroke: a dose-response meta-analysis of cohort studies

Background

There have been contradictory findings regarding the relationship between serum uric acid levels and prognosis in acute ischemic stroke. Whether this association is nonlinear due to uric acid's paradoxical properties (antioxidant and prooxidant) is unclear.

Methods

We searched PubMed, Web of Science, and Embase databases until December 2022. Cohort studies reporting serum uric acid levels and functional outcome, mortality, or neurological complications in patients with acute ischemic stroke were included. Summary effect estimates were calculated using a random-effect model. Moreover, dose-response relationships were assessed by the generalized least squares trend estimation.

Results

Altogether, 13 cohort studies were identified in this study. Compared to the lowest baseline serum uric acid levels, the highest levels were associated with decreased risk of poor functional outcome (OR = 0.70, 95% CI 0.54-0.91, I2 = 29%), hemorrhagic transformation (OR = 0.15, 95% CI 0.05-0.42, I2 = 79%), and post-stroke depression (OR = 0.04, 95% CI 0.00-0.95, I2 = 89%), but not associated with mortality and symptomatic intracerebral hemorrhage. A nonlinear relationship was observed in poor functional outcome (U-shaped, P for nonlinearity = 0.042), hemorrhagic transformation (inverse, P for nonlinearity = 0.001), and post-stroke depression (inverse, P for nonlinearity = 0.002). In addition, there was a single study reporting a U-shaped association in post-stroke epilepsy (P for nonlinearity <0.001). Furthermore, another study reported a positive curvilinear association in stroke recurrence (P for nonlinearity <0.05). The insufficient number of original articles for some prognostic indicators should be considered when interpreting the results of this meta-analysis.

Conclusion

In patients with acute ischemic stroke, serum uric acid levels are nonlinearly associated with the risk of poor functional outcome (U-shaped). More evidence is needed to confirm the association between serum uric acid levels and neurological complications following acute ischemic stroke.

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

MAIN PROBLEM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

Background

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

Materials and methods

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

Results

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

Conclusion

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

Interaction of Uric Acid and Neutrophil-to-Lymphocyte Ratio for Cardiometabolic Risk Stratification and Prognosis in Coronary Artery Disease Patients

Oxidative stress and inflammation are key factors in cardiometabolic diseases. We set out to evaluate the relationship between serum uric acid (UA) and the neutrophil-to-lymphocyte ratio (NLR) with cardiometabolic risk factors in coronary artery disease (CAD) patients, and their additive and multiplicative interactive effects on outcomes (cardiac death/CD and hard events (HE)-death plus reinfarction). A total of 2712 patients (67 ± 11 years, 1960 males) who underwent coronary angiography was retrospectively analyzed and categorized into no-CAD patients (n =806), stable-CAD patients (n =1545), and patients with acute myocardial infarction (AMI) (n =361). UA and NLR were reciprocally correlated and associated with cardiometabolic risk factors. During a mean follow-up period of 27 ± 20 months, 99-3.6% deaths, and 213-7.8% HE were registered. The Kaplan-Meier survival estimates showed significantly worse outcomes in patients with elevated UA or NLR levels. Multivariate Cox regression analysis demonstrated that NLR independently predicted CD and HE. There was no multiplicative interaction between UA and NLR; however, the use of measures of additive interaction evidenced a positive additive interaction between UA and NLR for CD and HE. Although it is clear that correlation does not imply causation, the coexistence of NRL and UA appears to have a synergistic effect, providing further information for the risk stratification of CAD patients.

The paradoxical relation between serum uric acid and outcomes of hip fracture in older patients after surgery: A 1-year follow-up study

BACKGROUND

The relation between serum uric acid and bone metabolism has been reported in many studies, but few studies have focused on serum uric acid and fracture rehabilitation. We aimed to explore the potential relationships between serum uric acid and outcomes of hip fractures.

METHODS

A total of 742 patients with hip fractures who underwent surgeries between December 2017 and February 2021 and met the inclusion criteria were included. The data of male and female patients were analyzed separately. Cox models with different adjusted forms were performed to explore the potential risk factors, and restricted cubic splines were used to determine the nonlinear relationships between serum uric acid and outcomes and optimal cutoff points of serum uric acid. Then, the outcomes were analyzed in the groups divided by cutoff points mentioned above, as well as groups divided by the diagnosis of hyperuricemia or gout.

RESULTS

Cox analysis showed that hyperuricemia or gout was associated with increased death risk, and a typical J-shaped curve was observed in the restricted cubic spline. For male patients, a serum uric acid of high level may relate to a high risk of 6-month (P = .008) and 1-year (P = .016) mortality, and a serum uric acid of low level may predict a poor 6-month free walking ability. For female patients, both a serum uric acid of high level and low level were associated with poor 1-year survival (all P < .05), and a serum uric acid of high level may relate to poor 6-month (P = .001) and 1-year (P = .001) free walking ability.

CONCLUSION

Patients with hyperuricemia or gout or patients with high and low levels of serum uric acid may face poor outcomes of hip fractures.

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

BACKGROUND AND AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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