Serum Uric Acid, Kidney Function and Acute Ischemic Stroke Outcomes in Elderly Patients: A Single-Cohort, Perspective Study

Long-term hyperuricemia impact on atrial fibrillation outcomes

BACKGROUND

No studies have been conducted to analyze the impact of serum uric acid (UA) levels on the outcome of atrial fibrillation (AF) patients. We aimed to evaluate the effect of hyperuricemia (HU) on the prognosis of AF.

METHODS AND RESULTS

Consecutive patients who consulted our emergency room for an episode of AF, already known or newly diagnosed, between January 1, 2010, and December 31, 2015 (n=2017) were enrolled. After applying exclusion criteria, 1772 patients were included. Serum UA levels in the 6 months before or after the date of the episode were recorded and classified into quartiles: Q1 (n=443) serum UA levels <4.6 mg/dL; Q2 (n=430) 4.6-5.6 mg/dL; Q3 (n=435) 5.7-6.9 mg/dL; and Q4 (n=464) ≥7 mg/dL. Two groups were differentiated: patients without HU (Q1-Q3) and those with HU (Q4). The mean follow-up was 3.7 ± 1.4 years. The primary endpoint was all-cause mortality during follow-up. Mortality during follow-up in the bivariate analysis was higher (p < 0.001) in patients with HU (52.1 %) compared to those without it (35.3 %), confirming multivariate Cox analysis of HU as an independent risk factor for death [hazard ratio 1.89 (1.59-2.25)]. Kaplan-Meier survival analysis showed a shorter survival time in patients with HU (log-rank test, p<0.001). Cox analysis confirmed significant differences in the risk of heart failure (30 % vs. 22 %) in patients with HU.

CONCLUSIONS

HU is independently associated with an increased risk for all-cause mortality and hospitalization for heart failure in patients with AF.

Association between decreases in serum uric acid levels and unfavorable outcomes after ischemic stroke: A multicenter hospital-based observational study

BACKGROUND

The association between clinical outcomes in ischemic stroke patients and decreases in serum uric acid levels, which often occur during the acute phase, remains unknown. Herein, we aimed to investigate the association using a large-scale, multicenter stroke registry.

METHODS

We analyzed 4,621 acute ischemic stroke patients enrolled in the Fukuoka Stroke Registry between June 2007 and September 2019 whose uric acid levels were measured at least twice during hospitalization (including on admission). The study outcomes were poor functional outcome (modified Rankin Scale score ≥3) and functional dependence (modified Rankin Scale score 3-5) at 3 months after stroke onset. Changes in uric acid levels after admission were evaluated using a decrease rate that was classified into 4 sex-specific grades ranging from G1 (no change/increase after admission) to G4 (most decreased). Multivariable logistic regression analyses were used to assess the associations between decreases in uric acid levels and the outcomes.

RESULTS

The frequencies of the poor functional outcome and functional dependence were lowest in G1 and highest in G4. The odds ratios (95% confidence intervals) of G4 were significantly higher for poor functional outcome (2.66 [2.05-3.44]) and functional dependence (2.61 [2.00-3.42]) when compared with G1 after adjusting for confounding factors. We observed no heterogeneity in results for subgroups categorized according to age, sex, stroke subtype, neurological severity, chronic kidney disease, or uric acid level on admission.

CONCLUSIONS

Decreases in serum uric acid levels were independently associated with unfavorable outcomes after acute ischemic stroke.

Serum uric acid to serum creatinine ratio predicts neurological deterioration in branch atheromatous disease

Background and objective

Branch atheromatous disease (BAD) makes patients prone to early neurological deterioration (END), resulting in poor prognosis. The aim of this study was to investigate the association between SUA/SCr and END in BAD stroke patients.

Methods

We conducted a retrospective study that included 241 patients with BAD-stroke within 48 h of symptom onset. We divided the patients into the END group and the no END group. END was defined as an NIHSS score increase of more than 2 points within 1 week. SUA/SCr was calculated by the concentration of serum uric acid and creatine (serum uric acid/serum creatine) on admission. Univariate and multivariate analyses were used to identify independent predictors of END in BAD-stroke patients.

Results

END was observed in 24.1% (58/241) of the patients in our study. Multiple logistic regression analyses showed that SUA/SCr (aOR, 0.716; 95% CI, 0.538-0.952; P = 0.022) and female sex (aOR, 0.469; 95% CI, 0.245-0.898; P = 0.022) were associated with END after adjusting for confounding factors. The predicted value of SUA/Scr for END was a sensitivity of 79.3%, a specificity of 44.8%, and an AUC of 0.609 (95% CI, 0.527-0.691, P < 0.05). The optimal cut-off value was 4.76.

Conclusion

SUA/SCr was negatively associated with the risk of END in BAD stroke patients.

Association between serum uric acid to serum creatinine ratio and poor functional outcomes in patients with acute ischemic stroke

BACKGROUND

The role of serum uric acid (SUA) in prognosis is controversial because SUA levels largely depend on renal clearance function. This study aimed to investigate the association between renal function-normalized SUA (SUA to serum creatinine ratio, SUA/SCr) and poor functional outcomes in patients with acute ischemic stroke (AIS).

METHODS

All patients were recruited from the Third China National Stroke Registry. Poor functional outcomes were defined by modified Rankin Scale (mRS) scores of 3-6 at 3 months or 2-6 at 1 year.

RESULTS

Among 8169 enrolled patients, the median SUA/SCr was 4.19 (interquartile range, 3.47-5.08). Compared with patients in the fourth quintile group, those in the first quintile group had higher proportions of mRS score 3-6 (odds ratio [OR] 1.55; 95% confidence interval [CI] 1.24-1.93) and mRS score 2-6 (OR 1.28; 95% CI 1.08-1.53) at 3 months. The addition of SUA/SCr to the conventional risk model had a greater incremental value than the addition of SUA or SCr alone. Subgroup analysis showed that the association was only significant in patients with normal kidney function (P for interaction<0.05). Similar results were found for outcomes at 1 year.

CONCLUSIONS

A lower level of SUA/SCr was associated with poor functional outcomes in patients with AIS at 3 months and at 1 year, suggesting the potential use of SUA/SCr in clinical practice as a preferable marker for stroke outcomes.

Efficacy and safety of reperfusion treatments in middle-old and oldest-old stroke patients

Introduction

Intravenous thrombolysis (IT) and mechanical thrombectomy (MT) have significantly changed the clinical outcome of acute ischaemic stroke (AIS). Concerns about possible complications often reduce the use of these treatment options for older patients, preferentially managed with antiplatelet therapy (AT). Aim of this study was to evaluate, in a population of middle-old (75–84 years) and oldest-old (≥ 85 years) subjects, the efficacy and safety of different treatments for AIS (IT, IT + MT, MT or AT), mortality and incidence of serious complications.

Patients and methods

All patients aged over 75 years admitted for AIS in two Stroke Units were enrolled. The physician in each case considered all treatment options and chose the best approach. NIHSS and modified Rankin Scale (mRS) were obtained and differences between admission and discharge scores, defined as delta(NIHSS) and delta(mRS), were calculated. The relationship between delta(NIHSS), delta(mRS) and type of procedure was analysed with a GLM/Multivariate model. Differences in mortality and incidence of serious complications were analysed with the chi-square test.

Results

A total of 273 patients, mean age 84.07 (± 5.47) years, were included. The Delta(NIHSS) was significantly lower in patients treated with AT than in those treated with IT and MT (p < 0.009 and p < 0.005, respectively). Haemorrhagic infarction occurrence was significantly lower (p < 0.0001) among patients treated with AT (10.6%) or IT (16.7%) compared to MT (34.9%) or MT + IT (37.0%). No significant difference was observed for in-hospital mortality. Age did not influence the outcome.

Conclusions

Our results suggest that IT and AT are effective and relatively safe approaches in middle-aged and older patients.

The Prognostic Value of Serum Uric Acid in Hospitalized Patients with Acute Cerebral Infarction

Background

Previous studies reported that the level of serum uric acid (SUA) was an important risk factor for acute cerebral infarction (ACI). However, the prognostic value of SUA levels in hospitalized patients with ACI has not been fully elucidated. The aim of this study was to investigate whether the SUA level on admission was associated with subsequent mortality in hospitalized patients with ACI.

Methods

The clinical data of ACI patients obtained from December 2017 to December 2019 were retrospectively reviewed. χ² and Kaplan–Meier methods were used to compare the clinical differences and overall survival between patients with or without hyperuricemia, respectively. Univariate and multivariate analyses were used to identify independent prognoses.

Results

In the total population, the in-hospital mortality of the hyperuricemia group was significantly higher than that of the normal uric acid group (P = 0.006). In the abnormal renal function group, the in-hospital mortality among the hyperuricemia group was significantly higher than the normal uric acid group (P = 0.002). However, there was no statistical difference of in-hospital mortality between the two groups in the normal renal function group (P = 0.321). Univariate and multivariate analyses showed that a previous history of diabetes (P = 0.018), hyperuricemia (P = 0.001), and National Institutes of Health Stroke Scale (NIHSS) score on admission (P ≤ 0.001) were independent factors for all samples. The hyperuricemia (P = 0.003) on admission were independent factors for patients with abnormal renal function.

Conclusions

In ACI patients with abnormal renal function, hyperuricemia may be associated with higher in-hospital mortality than patients with normal uric acid, and hyperuricemia may be an independent associated factor for in-hospital death in the subgroup patients.

Hyperuricemia enhances procoagulant activity of vascular endothelial cells through TMEM16F regulated phosphatidylserine exposure and microparticle release

The link between serum uric acid (SUA) and the risk of venous thromboembolism (VTE) is well established. Recent data suggested a causative role of UA in endothelial cells (ECs) dysfunction. However, the molecular mechanism of high UA on thrombogenesis is unknown. We investigate whether high UA induce phosphatidylserine (PS) externalization and microparticle (MP) shedding in cultured EC, and contribute to UA-induced hypercoagulable state. In the present study, we demonstrate that UA induces PS exposure and EMP release of EC in a concentration- and time-dependent manner, which enhances the procoagulant activity (PCA) of EC and inhibited over 90% by lactadherin in vitro. Furthermore, hyperuricemic rat model was used to evaluate the development of thrombi following by flow stasis in the inferior vena cava (IVC). Hyperuricemia group is more likely to form large and hard thrombi compared with control. Importantly, we found that TMEM16F expression is significantly upregulated in UA-treated EC, which is crucial for UA-induced PS exposure and MP formation. Additionally, UA increases the generation of reactive oxygen species (ROS), lipid peroxidation, and cytosolic Ca2+ concentration in EC, which might contribute to increased TMEM16F expression. Using confocal microscopy, we also observed disruption of the actin cytoskeleton, suggesting that depolymerization of actin filaments might be required for TMEM16F activation and followed by PS exposure and membrane blebbing in UA-treated EC. Our results demonstrate a thrombotic role of EC in hyperuricemia through TMEM16F-mediated PS exposure and MPs release.

CHA2DS2-VASc scores and Intermountain Mortality Risk Scores for the joint risk stratification of dementia among patients with atrial fibrillation

BACKGROUND

High CHA₂DS₂-VASc scores in atrial fibrillation (AF) patients are generally associated with increased risks of stroke and dementia. At lower CHA₂DS₂-VASc scores, there remains an unquantifiable cranial injury risk, necessitating an improved risk assessment method within these lower-risk groups.

OBJECTIVE

The purpose of this study was to determine whether sex-specific Intermountain Mortality Risk Scores (IMRS), a dynamic measures of systemic health that comprises commonly performed blood tests, can stratify dementia risk overall and among CHA₂DS₂-VASc score strata in AF patients.

METHODS

Female (n = 34,083) and male (n = 39,998) AF patients with no history of dementia were studied. CHA₂DS₂-VASc scores were assessed at the time of AF diagnosis and were stratified into scores of 0-1, 2, and ≥3. Within each CHA₂DS₂-VASc score stratum, patients were further stratified by IMRS categories of low, moderate, and high. Multivariable Cox hazard regression was used to determine dementia risk.

RESULTS

High-risk IMRS patients were generally older and had higher rates of hypertension, diabetes, heart failure, and prior stroke. Higher CHA₂DS₂-VASc score strata (≥3 vs ≤1: women, hazard ratio [HR] 7.77, 95% confidence interval [CI] 5.94-10.17, P < .001; men: HR 4.75, 95% CI 4.15-5.44, P < .001) and IMRS categories (high vs low: women, HR 3.09, 95% CI 2.71-3.51, P < .001; men, HR 2.70, 95% CI 2.39-3.06, P < .001) were predictive of dementia. When stratified by CHA₂DS₂-VASc scores, IMRS further identified risk in each stratum.

CONCLUSION

Both CHA₂DS₂-VASc scores and IMRS were independently associated with dementia incidence among AF patients. IMRS further stratified dementia risk among CHA₂DS₂-VASc score strata, particularly among those with lower CHA₂DS₂-VASc scores.

Effect of renal function on association between uric acid and prognosis in acute ischemic stroke patients with elevated systolic blood pressure

BACKGROUND AND AIMS

The prognostic value of uric acid in ischemic stroke remains controversial, and it is unclear whether renal function status modifies the prognostic value of uric acid in ischemic stroke patients.

METHODS

A total of 3284 acute ischemic stroke patients from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS) with creatinine and uric acid measurements were included in this analysis. The primary outcome was a composite of death and major disability (modified Rankin Scale score ≥3) at 1 year after stroke.

RESULTS

The prognostic value of uric acid in ischemic stroke was appreciably modified by patients' renal function status (p for interaction <0.05). After multivariate adjustment, higher uric acid level was significantly associated with a better prognosis in patients with normal renal function (odds ratio, 0.61; 95% confidence interval, 0.45-0.83), but not in those with abnormal renal function (odds ratio, 0.87; 95% confidence interval, 0.48-1.55), when two extreme quartiles were compared. Linear association between uric acid and primary outcome was observed among patients with normal renal function (p for linearity = 0.023).

CONCLUSION

The present study suggests that high serum uric acid concentration is associated with better prognosis in ischemic stroke patients with normal renal function, but not in those with abnormal renal function. The establishment of causality between increased uric acid levels and better stroke prognosis needs more suitably designed randomized clinical trials.

Associations between Uric Acid Level and 3-Month Functional Outcome in Acute Ischemic Stroke Patients Treated with/without Edaravone

BACKGROUND

Uric acid (UA), an antioxidant with neuroprotective effects, favorably affects stroke outcome. However, the effect has not been examined in patients treated with edaravone, a frequently used free radical scavenger. We investigated whether the use of edaravone affected the relationship between UA levels and outcome in acute ischemic stroke.

METHODS

We retrospectively evaluated 1,114 consecutive ischemic stroke patients with premorbid modified Rankin Scale (mRS) scores <2 admitted within 24 h of onset (mean, 74 years; median UA levels, 333 μmol/L). We divided the patients into 2 groups using the median UA value as a cutoff, a low UA group (≤333 μmol/L; n = 566) and a high UA group (>333 μmol/L; n = 548), and compared their clinical characteristics and favorable outcomes (mRS <2) at 90 days. We investigated the associations between UA levels and 90-day stroke outcome in patients with and without edaravone treatment.

RESULTS

The high UA group had a higher proportion of men, hypertension, atrial fibrillation, and cardioembolic stroke than the low UA group. The high UA group also had a higher proportion of patients with mRS <2 at 90 days (61.5 vs. 54.1%, p = 0.013), but the significance was diminished in multivariate analysis (OR 1.30, 95% CI 0.94-1.71). In subgroup analysis, the high UA group without edaravone exhibited a higher proportion of patients with mRS <2 at 90 days than the low UA group (OR 2.87, 95% CI 1.20-7.16). The high UA group with edaravone did not exhibit this difference.

CONCLUSIONS

In acute ischemic stroke, the favorable association between high UA levels and outcome at 90 days was not evident in patients treated with edaravone.