Renal dysfunction in acute stroke: an independent predictor of long-term all combined vascular events and overall mortality

Chronic kidney disease is associated with carotid atherosclerosis and symptomatic ischaemic stroke

Objective We aimed to investigate the relationships among chronic kidney disease (CKD), symptomatic ischaemic stroke, and carotid atherosclerosis. Methods We enrolled 455 patients who underwent carotid ultrasonography in our hospital, including 311 patients with symptomatic ischaemic stroke and 144 patients without symptomatic ischaemic stroke. Carotid intima-media thickness (IMT), the rate of internal carotid artery stenosis, and maximal plaque size were evaluated. Results The mean age of the patients was 68.5 ± 11.0 years and the mean estimated glomerular filtration rate (eGFR) was 68.8 ± 18.2 mL/min/1.73 m². After adjustment for cardiovascular risk factors, the mean IMT was significantly higher in patients with CKD than in those without CKD. The IMT and eGFR were negatively correlated in patients with stroke (r = -0.169). Multiple logistic regression analyses showed that mean IMT, plaque size, and internal carotid artery stenosis were significant determinants of symptomatic ischaemic stroke after adjustment of multivariate risk factors. Furthermore, the eGFR was a negative determinant of symptomatic ischaemic stroke after adjusting for classical risk factors (odds ratio [95% confidence interval] = 0.868 [0.769-0.979]). Conclusion CKD might be associated with the carotid atherosclerosis and symptomatic ischaemic stroke.

The Association between Glomerular Filtration Rate Estimated on Admission and Acute Stroke Outcome: The Shiga Stroke Registry

AIM

Although renal dysfunction has been identified as a novel risk factor affecting stroke prognosis, few have analyzed the association within large-scale population-based setting, using wide-range estimated glomerular filtration rate (eGFR) category. We aimed to determine the association of admission eGFR with acute stroke outcomes using data from a registry established in Shiga Prefecture, Japan.

METHODS

Following exclusion of patients younger than 18 years, with missing serum creatinine data, and with onset more than 7 days prior to admission, 2,813 acute stroke patients registered in the Shiga Stroke Registry year 2011 were included in the final analysis. The Japanese Society of Nephrology equation was used to estimate GFR. Multivariable logistic regression was performed to analyze the association of eGFR with all-cause in-hospital death (modified Rankin Scale [mRS] 6), and at-discharge death/disability (mRS 2-6). Separate analyses were conducted within stroke subtypes.

RESULTS

Compared to eGFR 60-89 mL/min/1.73 m2, adjusted odds ratios (ORs) and 95% confidence interval [95% CI] for in-hospital death (in the order of eGFR ＜45, 45-59, and ≥90 mL/min/1.73 m2) were 1.54 [1.04-2.27], 1.07 [0.72-1.58], and 1.04 [0.67-1.59]. Likewise, adjusted ORs [95% CI] for at-discharge death/disability were 1.54 [1.02-2.32], 0.97 [0.73-1.31], and 1.48 [1.06-2.05]. Similar pattern was further evident in the eGFR ＜45 mL/min/1.73 m2 group for both outcomes within acute ischemic stroke patients.

CONCLUSIONS

Our study has ascertained that in acute stroke, particularly ischemic stroke, low eGFR was significantly associated with in-hospital death and at-discharge death/disability. Additionally, high eGFR was found to be associated with at-discharge death/disability.

Thrombelastography Suggests Hypercoagulability in Patients with Renal Dysfunction and Intracerebral Hemorrhage

BACKGROUND

The objective of this study was to quantify coagulopathy using thrombelastography (TEG) in patients with renal dysfunction and intracerebral hemorrhage (ICH).

METHODS

We reviewed patients admitted with spontaneous ICH between November 2009 and May 2015. TEG was performed at the time of admission. Creatinine clearance (CCr) was calculated using the Cockroft-Gault equation. Patients were divided into 2 groups based on normal (CCr ≥ 90) or reduced renal function (CCr < 90). Multivariable regression models were conducted to compare the differences of TEG components.

RESULTS

A total of 120 patients were included in the analysis. The normal CCr group was younger (56.1 versus 62.3 years, P < .01), was more often male (73.6% versus 53.7%, P = .03), and had higher mean admission hemoglobin (14.2 versus 13.2 mEq/L, P < .01) than the reduced renal function group. The 2 groups were similar with respect to antiplatelet or anticoagulant use, coagulation studies, and baseline ICH volume. Following multivariate analysis, the reduced renal function group was found to have shorter K (1.5 versus 2.2 min, P = 004), increased angle (66 versus 62.2 degrees, P = .04), increased MA (67.3 versus 62.3, P = .02), and increased G (11.3 versus 9.9 dynes/cm², P = .04) compared with the normal group. Mortality, poor functional outcome (modified Rankin Scale score 4-6), hematoma enlargement, hospital length of stay, and surgical interventions were not different between the 2 groups.

CONCLUSIONS

Patients with ICH and reduced CCr display faster clotting rate and increased clot strength, suggesting that patients with renal dysfunction present with a relatively hypercoagulable state based on TEG parameters thought to reflect platelet activity.

Incidence, Risk Factors, and Outcome of Acute Kidney Injury in Neurocritical Care

PURPOSE

Acute kidney injury (AKI) is a severe complication in medical and surgical intensive care units accounting for a high morbidity and mortality. Incidence, risk factors, and prognostic impact of this deleterious condition are well established in this setting. Data concerning the neurocritically ill patients is scarce. Therefore, aim of this study was to determine the incidence of AKI and elucidate risk factors in this special population.

METHODS

Patients admitted to a specialized neurocritical care unit between 2005 and 2011 with a length of stay above 48 hours were analyzed retrospectively for incidence, cause, and outcome of AKI (AKI Network-stage ≥2).

RESULTS

The study population comprised 681 neurocritically ill patients from a mixed neurosurgical and neurological intensive care unit. The prevalence of chronic kidney disease (CKD) was 8.4% (57/681). Overall incidence of AKI was 11.6% with 36 (45.6%) patients developing dialysis-requiring AKI. Sepsis was the main cause of AKI in nearly 50% of patients. Acute kidney injury and renal replacement therapy are independent predictors of worse outcome (hazard ratio [HR]: 3.704; 95% confidence interval [CI]: 1.867-7.350; P < .001; and HR: 2.848; CI: 1.301-6.325; P = .009). Chronic kidney disease was the strongest independent risk factor (odds ratio: 12.473; CI: 5.944-26.172; P < .001), whereas surgical intervention or contrast agents were not associated with AKI.

CONCLUSIONS

Acute kidney injury in neurocritical care has a high incidence and is a crucial risk factor for mortality independently of the underlying neurocritical condition. Sepsis is the main cause of AKI in this setting. Therefore, careful prevention of infectious complications and considering CKD in treatment decisions may lower the incidence of AKI and hereby improve outcome in neurocritical care.

Acute Kidney Injury Following Acute Ischemic Stroke and Intracerebral Hemorrhage: A Meta-Analysis of Prevalence Rate and Mortality Risk

BACKGROUND

The epidemiology of acute renal dysfunction after stroke is routinely overlooked following stroke events. Our aim in this meta-analysis is to report the prevalence of acute kidney injury (AKI) following acute stroke and its impact on mortality.

METHODS

A systematic literature search was performed on PubMed, EMBASE and Google Scholar for observational studies examining the prevalence and mortality risk of stroke patients with AKI as a complication. The pooled prevalence rates and odds ratios for mortality risk were calculated using subgroup analyses between the stroke subtypes: acute ischemic stroke (AIS) and intracerebral hemorrhage (ICH).

RESULTS

A total of 12 studies (4,532,181 AIS and 615,636 ICH) were included. The pooled prevalence rate of AKI after all stroke types was 11.6% (95% CI 10.6-12.7). Subgroup analyses revealed that the pooled prevalence rate of AKI after AIS was greater but not statistically significantly different than ICH (19.0%; 95% CI 8.2-29.7 vs. 12.9%; 95% CI 10.3-15.5, p = 0.5). AKI was found to be a significant risk factor of mortality in AIS (adjusted OR [aOR] 2.23; 95% CI 1.28-3.89; I2 = 98.8%), whereas this relationship did not reach statistical significance in ICH (aOR 1.20; 95% CI 0.68-2.12; I2 = 74.2%).

CONCLUSIONS

This meta-analysis provides evidence that AKI is a common complication following both AIS and ICH and it is associated with increased mortality following AIS but not ICH. This highlights the need for early assessment of renal function in the acute phase of AIS, in particular, and avoidance of factors than may induce AKI in vulnerable patients.

Acute Kidney Injury and Risk of Incident Heart Failure Among US Veterans

BACKGROUND

Acute kidney injury (AKI) is common and associated with poor outcomes. Heart failure is a leading cause of cardiovascular disease among patients with chronic kidney disease. The relationship between AKI and heart failure remains unknown and may identify a novel mechanistic link between kidney and cardiovascular disease.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

We studied a national cohort of 300,868 hospitalized US veterans (2004-2011) without a history of heart failure.

PREDICTOR

AKI was the predictor and was defined as a 0.3-mg/dL or 50% increase in serum creatinine concentration from baseline to the peak hospital value. Patients with and without AKI were matched (1:1) on 28 in- and outpatient covariates using optimal Mahalanobis distance matching.

OUTCOMES

Incident heart failure was defined as 1 or more hospitalization or 2 or more outpatient visits with a diagnosis of heart failure within 2 years through 2013.

RESULTS

There were 150,434 matched pairs in the study. Patients with and without AKI during the index hospitalization were well matched, with a median preadmission estimated glomerular filtration rate of 69mL/min/1.73m². The overall incidence rate of heart failure was 27.8 (95% CI, 19.3-39.9) per 1,000 person-years. The incidence rate was higher in those with compared with those without AKI: 30.8 (95% CI, 21.8-43.5) and 24.9 (95% CI, 16.9-36.5) per 1,000 person-years, respectively. In multivariable models, AKI was associated with 23% increased risk for incident heart failure (HR, 1.23; 95% CI, 1.19-1.27).

LIMITATIONS

Study population was primarily men, reflecting patients seen at Veterans Affairs hospitals.

CONCLUSIONS

AKI is an independent risk factor for incident heart failure. Future studies to identify underlying mechanisms and modifiable risk factors are needed.

The impact of acute kidney injury on in-hospital mortality in acute ischemic stroke patients undergoing intravenous thrombolysis

INTRODUCTION

Acute kidney injury (AKI) increases the risk of death in acute ischemic stroke (AIS) patients. Intravenous thrombolytic therapy (iv. rt-PA) seems to be the most effective treatment for AIS patients. The effects of AKI on iv. rt-PA treated AIS cases is less studied. Our paper addresses this issue.

METHODS

45 consecutive stroke patients treated with iv. rt-PA (median age = 64 years; 29 male) and 59 age and sex matched controls not eligible for iv. rt-PA have been enrolled in our study. Subjects were followed-up until hospital release or death (median follow up time = 12 days).

RESULTS

The prevalence of AKI did not differ between iv. rt-PA treated patients and controls (35.5% vs. 33.89%). In both groups, AKI was associated with increased in-hospital mortality: 50.0% vs. 3.4% p<0.0001 (in the rt-PA treated), and 45% vs. 30.7% (in controls). AKI iv. rt-PA treated patients had a significantly higher risk of in hospital mortality as compared to the no-AKI iv. rt-PA treated (HR = 15.2 (95%CI [1.87 to 124.24]; P = 0.011). In a Cox-multivariate model, the presence of AKI after iv. rt-PA remained a significant factor (HR = 8.354; p = 0.041) influencing the in-hospital mortality even after correction for other confounding factors. The independent predictors for AKI were: decreased eGFR baseline and elevated serum levels of uric acid at admission, (the model explained 60.2% of the AKI development).

CONCLUSIONS

The risk of AKI was increased in AIS patients. Thrombolysis itself did not increase the risk of AKI. In the iv. rt-PA patients, as compared to non-AKI, those which developed AKI had a higher rate of in-hospital mortality. The baseline eGFR and the serum uric acid at admission were independent predictors for AKI development in the iv. rt-PA treated AIS patients.

Sequelae of AKI

Large epidemiologic studies in a variety of patient populations reveal increased morbidity and mortality that occur months to years after an episode of acute kidney injury (AKI). Even milder forms of AKI have increased associated morbidity and mortality. Residual confounding may account for these findings, but considering the huge number of individuals afflicted with AKI, the sequelae of AKI may be a very large public health burden. AKI may simply be a marker for increased risk, but there is increasing evidence that it is part of the causal pathway to chronic kidney disease. These studies have upended the traditional view that AKI survivors who returned to baseline, or near baseline renal function, do not suffer additional long-term consequences. Recovery of renal function after AKI, short of independence from renal replacement therapy, is yet to be clearly defined but may be of significant importance in the management of AKI survivors. The association between AKI in patients who undergo cardiac surgery and clinical outcomes is of considerable importance to clinicians, surgeons, and anesthesiologists alike and is a major focus of this review.

Renal dysfunction and chronic kidney disease in ischemic stroke and transient ischemic attack: A population-based study

Background and purpose

The prevalence of chronic kidney disease (estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m2 for ≥3 months, chronic kidney disease (CKD)) in ischemic stroke and transient ischemic attack (TIA) is unknown, as estimates have been based on single-point estimates of renal function. Studies investigating the effect of renal dysfunction (eGFR < 60 mL/min per 1.73 m2, renal dysfunction) on post-stroke outcomes are limited to hospitalized cohorts and have provided conflicting results.

Methods

We investigated rates, determinants and outcomes of renal dysfunction in ischemic stroke and TIA in the North Dublin Population Stroke Study. We also investigate the persistence of renal dysfunction in 90-day survivors to determine the prevalence of CKD. Ascertainment included hot and cold pursuit using multiple overlapping sources. Survival analysis was performed using Kaplan–Meier survival curves and Cox proportional hazards modeling.

Results

In 547 patients (ischemic stroke in 76.4%, TIA in 23.6%), the mean eGFR at presentation was 63.7 mL/min/1.73 m2 (SD 22.1). Renal dysfunction was observed in 44.6% (244/547). Among 90-day survivors, 31.2% (139/446) met criteria for CKD. After adjusting for age and stroke severity, eGFR < 45 mL/min/1.73 m2 (hazard ratio 2.53, p = 0.01) independently predicted 28-day fatality but not at two years. Poor post-stroke functional outcome (Modified Rankin Scale 3–5) at two years was more common in those with renal dysfunction (52.5% vs. 20.6%, p < 0.001). After adjusting for age, stroke severity and pre-stroke disability, renal dysfunction (OR 2.17, p = 0.04) predicted poor functional outcome.

Conclusion

Renal dysfunction and CKD are common in ischemic stroke and TIA. Renal dysfunction is associated with considerable post-stroke morbidity and mortality. Further studies are needed to investigate if modifiable mechanisms underlie these associations.

Renal Dysfunction Is an Independent Risk Factor for Poor Outcome in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis: A New Cutoff Value

Objective. This study was set to assess the effect of renal dysfunction on outcome of stroke patients treated with intravenous thrombolysis (IVT). Methods. This multicenter research involved 403 patients from January 2009 to March 2015. Patients were divided into two groups: (1) control group with GFR ≥ 45 mL/min/1.73 m² and (2) low GFR group with GFR < 45 mL/min/1.73 m². Outcome measurements were poor outcome (mRS 3–6) and mortality at 3 months and symptomatic intracerebral hemorrhage (SICH) within the first 24–36 hours. Univariate and multivariate regression analyses were performed, and odds ratios (ORs) were determined at 95% confidence intervals (CIs). Results. Univariate analyses determined that every decrease of GFR by 10 mL/min/1.73 m² significantly increased the risk of poor outcome (OR 1.19, 95% CI 1.09–1.30, p < 0.001) and mortality (OR 1.18, 95% CI 1.06–1.32, p = 0.002). In multivariate regression, adjusted for all variables with p value < 0.1, low GFR (GFR < 45 versus GFR equal to or more than 45) was associated with poor outcome (OR adjusted 2.15, 95% CI 1.01–4.56, p = 0.045). Conclusion. In IVT for acute stroke, renal dysfunction with GFR < 45 mL/min/1.73 m² before treatment determined increased odds for poor outcome compared to GFR of more than 45 mL/min/1.73 m².

Prevalence and Significance of Unrecognized Renal Dysfunction in Patients with Stroke

BACKGROUND

Unrecognized renal dysfunction, defined as an estimated glomerular filtration rate <60 mL/min/1.73 m(2) in the presence of normal serum creatinine levels, is a common comorbidity among patients with various cardiovascular conditions. The current study was aimed to evaluate the prevalence and clinical significance of unrecognized renal dysfunction in patients with acute stroke.

METHODS

The cohort consisted of patients with acute stroke included in the prospective National Acute Stroke ISraeli (NASIS) registry. Unrecognized renal insufficiency was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m(2) in the presence of serum creatinine ≤1.2 mg/dL. The 2 primary outcomes were in-hospital mortality and the composite of in-hospital mortality or severe disability at hospital discharge.

RESULTS

Of the 7900 patients with stroke included in the study, 5571 (70.5%) had normal renal function, 1510 (19.1%) had recognized renal insufficiency, and 819 (10.4%) had unrecognized renal insufficiency. Mortality rates were higher in patients with recognized and unrecognized renal insufficiency compared with patients with normal renal function (9.9%, 9.1%, and 4.4%, respectively, P < .0001). Adjusted odds ratios (ORs) for in-hospital mortality were higher for patients with renal dysfunction recognized (OR, 2.1; 95% confidence interval [CI], 1.6-2.7; P < .001) or unrecognized (OR, 1.6; 95% CI, 1.1-2.2; P = .006) compared with patients with normal renal function. Likewise, adjusted ORs for the composite of in-hospital mortality or severe disability at hospital discharge were higher for patients with renal dysfunction recognized (OR, 1.3; 95% CI, 1.1-1.5; P = .004) or unrecognized (OR, 1.2; 95% CI, 1.01-1.5; P = .04).

CONCLUSIONS

Unrecognized renal insufficiency is common among patients with acute stroke and is associated with adverse short-term outcomes.

Renal Dysfunction in Post-Stroke Patients

BACKGROUND

The presence of chronic kidney disease (CKD) is an indicator of a worse long-term prognosis in patients with ischemic stroke (IS). Unfortunately, not much is known about renal function in the population of post-IS subjects. The aim of our study was to assess the prevalence of renal damage and impaired renal function (IRF) in the population of post-IS subjects.

METHODS

This prospective analysis concerned 352 consecutive post-IS survivors hospitalized in Pomeranian stroke centers (Poland) in 2009. In this group estimated glomerular filtration rate (eGFR) according to MDRD (modification of diet in renal diseases) and CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formulas and urine albumin/creatinine ratio (ACR) were determined.

RESULTS

Among survivors decreased eGFR (<60 mL/min./1.73m2 according to MDRD or CKD-EPI) or ACR≥30mg/g were detected in 40.38% (23.07% Men, 55.32% Women; P<0.01). The highest prevalence of IRF was noted in post-IS subjects with atheromatic and lacunar IS. In multivariate analysis the ACR≥30mg/g was predicted by older age, diabetes mellitus (DM) and physical disability (modified Rankin scale 3-5 pts.). The association with reduced eGFR was proved for sex (female), DM and physical disability.

CONCLUSIONS

CKD is a frequently occurring problem in the group of post-IS subjects, especially after lacunar and atheromatic IS. Post-IS patients, mainly the elderly women, with physical disability and diabetes mellitus, should be regularly screened for CKD. This could reduce the risk of further cardiovascular events and delay the progression of IRF.

Prognostic value of urine dipstick proteinuria on mortality after acute ischemic stroke

BACKGROUND AND AIMS

Proteinuria is a marker of kidney disease and a strong risk factor for cardiovascular diseases including stroke. This study was aimed at investigating the prognostic value of proteinuria measured by urine dipstick in patients with acute ischemic stroke.

METHODS

This post-hoc analysis of a prospective cohort study included 3404 consecutive patients who had been admitted for acute ischemic stroke between November 2005 and June 2013. Proteinuria was defined as a trace or more of protein on a urine dipstick test routinely performed at admission. Date and cause of death until December 31, 2013 were collected. We investigated the association of proteinuria with all-cause mortality, cardiovascular mortality (defined as ICD-10 codes I00-I99), and non-cardiovascular mortality.

RESULTS

Proteinuria was present in 12.8% of the 3404 patients. During the mean follow-up period of 3.56 ± 2.22 years, there were 681 cases of all-cause mortality (460 cardiovascular deaths and 221 non-cardiovascular deaths). Multivariate Cox regression analysis showed that the presence of proteinuria was an independent risk factor for all-cause mortality (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.40-2.04), cardiovascular mortality (adjusted HR 1.65, 95% CI 1.31-2.08), and non-cardiovascular mortality (adjusted HR 1.59, 95% CI 1.13-2.23). Adding proteinuria to the multivariate Cox models moderately improved the model performance for all-cause mortality (integrated area under curve [95% CI]: from 0.800 [0.784-0.816] to 0.803 [0.788-0.818], p = 0.026).

CONCLUSIONS

Proteinuria, which was detected on a urine dipstick test, was a significant predictor of mortality after acute ischemic stroke.

Cognitive function assessment in patients with end- stage renal disease in Nigeria: A single center experience

AIM

The purpose of this comparative study was to evaluate cognitive function in end-stage renal disease (ESRD) patients in comparison with age, sex, and level of education-matched control.

MATERIALS AND METHODS

This is a cross-sectional study involving 80 ESRD patients receiving maintenance hemodialysis treatment and recruited conservatively at the nephrology unit of our hospital. Eighty apparently healthy control, that were matched with the patients for age, sex and education, were also recruited. Following exclusion of depression and severe functional disability, a computer-assisted neuropsychological test, the FePsy, was used to assess  memory, psychomotor speed, concentration and attention using simple auditory and visual reaction time tasks, recognition memory tests (RMTs), finger tapping task, and binary choice task (BCT) for both the ESRD patients and controls.

RESULTS

ESRD patients performed worse on simple auditory and visual reaction time tasks (P < 0.05), RMTs (P < 0.05), finger tapping task (P < 0.05), BCT, and computerized visual search task (P < 0.05).

CONCLUSION

Performance in memory, psychomotor tasks, concentration, and attention tasks were found to be reduced among patients with ESRD compared with age, sex and level of education-matched control.

Chronic kidney disease and cognitive impairment among the very old in China

BACKGROUND AND AIMS

Previous studies have confirmed that chronic kidney disease (CKD) influences the cognitive function of adults. However, few studies focused the relationships among the very old. The purpose of this study was to determine whether CKD is associated with cognitive impairment among nonagenarians and centenarians in China.

METHOD

This work was conducted as a cross-sectional study. 767 unrelated Chinese nonagenarians and centenarians participated in the study. The 30-item mini-mental state examination (MMSE) was used to assess cognitive function. Estimated glomerular filtration rate (eGFR) was estimated using the Modification of Diet in Renal Disease equation (Chinese version). CKD was defined as eGFR less than 60 mL/min/1.73 m(2).

RESULTS

The cohort was 68.2 % female and mean (SD) age was 93.8 (3.5) years. There were 113 (14.7 %) and 577 (75.2 %) prevalent cases of CKD and cognitive impairment, respectively. After adjusting for sociodemographic variables, multivariate logistic regression showed CKD was not significantly associated with cognitive impairment (OR 0.81, 95 % CI 0.49-1.33). When other disease-related variables were adjusted, the result remained substantially unchanged. However, age, gender, education and income may largely or entirely explain the lack of association between CKD and cognitive impairment as measured according to the MMSE.

CONCLUSION

Among Chinese nonagenarians and centenarians, CKD was not directly correlated with cognitive impairment.

Kidney Dysfunction Increases Mortality and Incident Events after Young Stroke: The FUTURE Study

Background: In about 30% of young stroke patients, no cause can be identified. In elderly patients, kidney dysfunction has been suggested as a contributing risk factor for mortality as well as stroke. There are hypotheses that novel non-traditional risk factors, like chronic inflammation and oxidative stress, are involved in chronic kidney disease, affecting the cerebral microvasculature that would in turn lead to stroke. Our objective is to investigate the influence of kidney dysfunction on long-term mortality and incident vascular events after stroke in young adults aged 18 through 50 and if this relationship would be independent of other cardiovascular risk factors. Methods: We prospectively included 460 young stroke patients with an ischemic stroke or transient ischemic attack admitted to our department between January 1, 1980 and November 1, 2010. Follow-up was done between 2014 and 2015. Estimated glomerular filtration rate (eGFR) was calculated from baseline creatinine levels and was divided in 3 subgroups: eGFR <60, 60-120 and >120 ml/min/1.73 m2. Cox proportional hazard models were used to determine the effect of kidney dysfunction on mortality and incident vascular events, adjusting for cardiovascular risk factors. Results: An eGFR <60 (HR 4.6; 95% CI 2.6-8.2) was associated with an increased risk of death and an increased risk of incident stroke (HR 4.1; 95% CI 1.9-9.0) independent of cardiovascular risk factors, but it was not associated with other vascular events. The point estimate for the 15-year cumulative mortality was 70% (95% CI 46-94) for patients with a low eGFR, 24% (95% CI 18-30) for patients with a normal eGFR and 30% (95% CI 12-48) for patients with a high eGFR. The point estimate for the 15-year cumulative risk of incident stroke was 45% (95% CI 16-74) for patients with a low eGFR, 13% (95% CI 9-17) for patients with a normal eGFR and 8% (95% CI 0-18) for patients with a high eGFR. Conclusions: Kidney dysfunction is related to long-term mortality and stroke recurrence, but not to incident cardiovascular disease, on average 11 years after young stroke. This warrants a more intensive follow-up of young stroke patients with signs of kidney dysfunction in the early phase. In addition, the clear association between kidney dysfunction and incident stroke seen in our young stroke population might be a first step in the recognition of kidney dysfunction as a new risk factor for the development of stroke at young age. Also, it can lead to new insights in the etiological differences between cardiovascular and cerebrovascular disease.

Which Comorbidities and Complications Predict Ischemic Stroke Recovery and Length of Stay?

OBJECTIVES

Stroke is the second most common cause of death worldwide and can lead to significant disability and long-term costs. Length of stay (LOS) is the most predictive factor in determining inpatient costs. In the present study, factors that affect disability and LOS among ischemic stroke patients admitted to an urban community hospital and 2 university-based teaching hospitals were assessed.

METHODS

Data for consecutive patients with acute ischemic strokes were collected, by reviewing discharge diagnosis International Classification of Diseases codes. A data mining process was used to analyze admission data. Data regarding comorbidities and complications were abstracted by mining the secondary diagnoses for their respective International Classification of Diseases-9 codes. The primary outcome was LOS, calculated from the dates of admission and dates of discharge. The second outcome of interest was disability, which was evaluated by the modified Rankin score at the time of discharge.

RESULTS

LOS progressively increased with greater disability. Greater age and higher National Institute of Health Stroke Scale at admission were associated with both higher disability and longer LOS. Presence of congestive heart failure or chronic kidney disease, atrial fibrillation, other arrhythmias (preexisting or new onset), and development of acute renal failure were associated with greater LOS but not greater disability status. Patients with a previous stroke and those that developed urinary tract infection as a complication had higher disability.

CONCLUSIONS

Greater age and higher National Institute of Health Stroke Scale at admission were associated with both higher disability and longer LOS. Congestive heart failure, CRF, presence of arrhythmias, and development of acute renal failure were associated with greater LOS. The development of urinary tract infection caused higher disability.

Chronic Kidney Disease and Carotid Atherosclerosis in Patients With Acute Stroke

BACKGROUND AND PURPOSE

Chronic kidney disease (CKD) is increasingly recognized as an independent risk factor for cardiovascular disease and stroke. Our aim was to examine the association between estimated glomerular filtration rate (eGFR) and carotid plaques, stenosis and occlusions, and to assess whether CKD and its severity affect carotid atherosclerosis in a cohort of unselected patients with acute stroke.

METHODS

A total of 249 consecutive patients with acute stroke (ischemic or hemorrhagic) were included in this study and baseline eGFR, carotid intima-media thickness (cIMT), and carotid stenosis were evaluated. The eGFR was calculated using the modified Modification of Diet in Renal Disease equation, which was adjusted for data from Chinese CKD patients. An eGFR rate of <60 mL/min/1.73 m was defined as CKD. The cIMT and carotid plaques were detected by carotid ultrasound.

RESULTS

CKD, defined as eGFR<60 mL/min/1.73 m, was found in 66 individuals (26.50%). Among the 5 subtypes, the level of low-density lipoprotein cholesterol was significantly higher in the moderate and severe stenosis groups compared with the normal, elevated cIMT and mild stenosis groups (P<0.01). The value of eGFR gradually decreased with increasing degree of carotid stenosis, and the differences between the groups were statistically significant (P<0.01). On linear regression analysis, eGFR was negatively correlated with the degree of carotid stenosis (r=0.03; P<0.05). On ordinal logistic regression analysis, eGFR was an independent risk factor associated with carotid atherosclerosis (1.05; 95% confidence interval, 0.47-1.63).

CONCLUSIONS

There was a significant burden of atherosclerosis among individuals with CKD. CKD is an independent predictor of carotid plaques, stenoses, and occlusions in patients with acute stroke.

Estimated GFR and the Effect of Intensive Blood Pressure Lowering After Acute Intracerebral Hemorrhage

BACKGROUND

The kidney-brain interaction has been a topic of growing interest. Past studies of the effect of kidney function on intracerebral hemorrhage (ICH) outcomes have yielded inconsistent findings. Although the second, main phase of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2) suggests the effectiveness of early intensive blood pressure (BP) lowering in improving functional recovery after ICH, the balance of potential benefits and harms of this treatment in those with decreased kidney function remains uncertain.

STUDY DESIGN

Secondary analysis of INTERACT2, which randomly assigned patients with ICH with elevated systolic BP (SBP) to intensive (target SBP<140mmHg) or contemporaneous guideline-based (target SBP<180mmHg) BP management.

SETTING & PARTICIPANTS

2,823 patients from 144 clinical hospitals in 21 countries.

PREDICTORS

Admission estimated glomerular filtration rates (eGFRs) of patients were categorized into 3 groups based on the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation: normal or high, mildly decreased, and moderately to severely decreased (>90, 60-90, and <60mL/min/1.73m(2), respectively).

OUTCOMES

The effect of admission eGFR on the primary outcome of death or major disability at 90 days (defined as modified Rankin Scale scores of 3-6) was analyzed using a multivariable logistic regression model. Potential effect modification of intensive BP lowering treatment by admission eGFR was assessed by interaction terms.

RESULTS

Of 2,623 included participants, 912 (35%) and 280 (11%) had mildly and moderately/severely decreased eGFRs, respectively. Patients with moderately/severely decreased eGFRs had the greatest risk for death or major disability at 90 days (adjusted OR, 1.82; 95% CI, 1.28-2.61). Effects of early intensive BP lowering were consistent across different eGFRs (P=0.5 for homogeneity).

LIMITATIONS

Generalizability issues arising from a clinical trial population.

CONCLUSIONS

Decreased eGFR predicts poor outcome in acute ICH. Early intensive BP lowering provides similar treatment effects in patients with ICH with decreased eGFRs.

Chronic kidney disease and intravenous thrombolysis in acute stroke: A systematic review and meta-analysis

BACKGROUND

The association between chronic kidney disease (CKD) and hemorrhagic complications or clinical outcomes in patients treated with intravenous (IV) thrombolytic agents is controversial.

METHODS

We searched multiple databases for studies on the association between CKD and symptomatic intracerebral hemorrhage (ICH) and/or clinical outcomes in acute stroke patients treated with IV tissue plasminogen activator (tPA). Observational studies that evaluated the association between CKD and outcomes after adjusting for other confounding factors were eligible. We assessed study quality and performed a meta-analysis. The main outcome was symptomatic ICH. The secondary outcomes were poor functional status at 3 months using the modified Rankin Scale, mortality at 3 months, and any ICH.

RESULTS

Seven studies were selected based on our eligibility criteria. Of 7168 patients treated with IV tPA, 2001 (27.9%) had CKD. Patients with CKD had a higher risk of symptomatic ICH and mortality [pooled odds ratio (OR) 1.56, 95% confidence interval (CI) 1.05-2.33 and pooled OR 1.70, 95% CI 1.03-2.81, respectively]. Patients with CKD were likely to have an increased risk of poor outcome at 3 months. There was no significant association between CKD and any ICH.

CONCLUSIONS

Chronic kidney disease may significantly affect symptomatic hemorrhagic complications and poor clinical outcomes following administration of IV tPA.

Association between renal dysfunction and 3-year mortality in patients with acute first-ever ischemic stroke

OBJECTIVE

The influence of renal dysfunction on the clinical presentation and outcomes of patients with acute ischemic stroke is still controversial. We investigate the influence of renal dysfunction on the outcomes of patients with acute first-ever ischemic stroke.

METHODS

Nine-hundred thirty-four patients with acute first-ever ischemic stroke were enrolled and followed for 3 years. Renal function was assessed using the equation of the Modification Diet for Renal Disease for estimated glomerular filtration rate (eGFR). Serum creatinine levels were obtained within 3 days of acute stroke onset. Reduced eGFR was defined as eGFR<60ml/min/1.73m(2). Clinical presentation, risk factors for stroke, laboratory data, co-morbidities, and outcomes were recorded.

RESULTS

Total 264 patients (28.3%) had a reduced eGFR. The prevalence of older age, hypertension, and atrial fibrillation was significantly higher in patients with a reduced eGFR. Total anterior circulation syndrome occurred more frequently among patients with a reduced eGFR (P=0.010). Multivariate Cox regression revealed that a reduced eGFR is a significant predictor of 3-year mortality (HR=1.67, 95% CI=1.06-2.62, P=0.026).

CONCLUSION

Reduced eGFR during the acute stroke stage is associated with increased risk of 3-year mortality. Furthermore, risk of acute complications and poor functional outcomes following discharge was significantly higher in patients with a reduced eGFR.

Thrombolysis in chinese ischemic stroke patients with renal dysfunction

BACKGROUND

Current data concerning the relationship between renal function and clinical outcome among stroke patients treated with intravenous thrombolytic therapy are conflicting. Our aim is to analyze whether the clinical outcome of Chinese ischemic stroke patients treated with thrombolytic therapy is affected by the presence of renal dysfunction.

METHODS

Chinese patients who received intravenous thrombolytic therapy for acute ischemic stroke were recruited. Renal dysfunction was defined as an estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m(2). The primary outcome was independent function (modified Rankin Scale, mRS, 0-2) at 3 months, while secondary outcomes included early improvement of the National Institute of Health Stroke Scale (NIHSS) score of ≥4 points at 24 h, symptomatic intracerebral hemorrhage (ICH) within 36 h of treatment and 30-day mortality.

RESULTS

A total of 199 patients were recruited, of whom 51.3% had renal dysfunction. There were no significant differences in functional independence at 3 months, NIHSS improvement at 24 h post-thrombolysis and 30-day mortality between patients with or without renal dysfunction. Multivariate analysis showed that eGFR as a continuous variable was not an independent risk factor for symptomatic ICH.

CONCLUSION

Chinese ischemic stroke patients with renal dysfunction who received thrombolytic therapy had clinical outcomes similar to those without renal dysfunction.

Urea

Urea is generated by the urea cycle enzymes, which are mainly in the liver but are also ubiquitously expressed at low levels in other tissues. The metabolic process is altered in several conditions such as by diets, hormones, and diseases. Urea is then eliminated through fluids, especially urine. Blood urea nitrogen (BUN) has been utilized to evaluate renal function for decades. New roles for urea in the urinary system, circulation system, respiratory system, digestive system, nervous system, etc., were reported lately, which suggests clinical significance of urea.

Ischemic stroke: the impact of renal dysfunction on 1-year mortality

BACKGROUND

Atherosclerosis is accelerated in patients with different stages of chronic renal failure. Renal dysfunction predicts mortality in patients with myocardial infarction and congestive heart failure. Less is known about the impact of renal dysfunction on mortality after ischemic stroke. The aim of the study was to investigate the impact of renal dysfunction on 1-year mortality.

PATIENTS AND METHODS

All 390 patients (207 men and 183 women) suffered from ischemic stroke in 1-year period were included in our study. Telephonic follow-up after 1 year was performed. The mean age of our patients was 71.0 ± 11.6 years, ranged from 36 to 96 years. Glomerular filtration rate (GFR) was calculated according to abbreviated Modification of Diet in Renal Disease formula. At admission and at discharge National Institutes of Health Stroke Scale (NIHSS) were performed.

RESULTS

The mean GFR in our patients was 66.0 ± 20.68 ml/min/1.73 m(2). There were 123 (31.5 %) deaths in 1-year period. Patients who died were older (P < 0.001), had higher NIHSS at admission and at discharge (both P < 0.001), higher high-sensitive C-reactive protein (P = 0.002), lower albumin (P < 0.001), lower GFR (P = 0.044), had more frequent atrial fibrillation (P < 0.001), and were less frequent actual smokers (P = 0.003). No differences in presence of diabetes and hypertension, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides between patients who died or survived were found. With Cox multivariable regression analysis age (P = 0.037), gender (P = 0.005), NIHSS at admission (P = 0.005) and discharge (P < 0.001), albumin (P = 0.005) and also GFR (P = 0.025) were predictors of 1-year mortality.

CONCLUSIONS

In patients with ischemic stroke, renal dysfunction (decreased GFR) was associated with 1-year mortality. GFR was independent predictor of mortality.

A low baseline glomerular filtration rate predicts poor clinical outcome at 3 months after acute ischemic stroke

Background and Purpose

Chronic kidney disease (CKD) is an established risk factor for numerous cardiovascular diseases including stroke. The relationship between the baseline estimated glomerular filtration rate (eGFR) and clinical 3-month outcomes in patients with acute ischemic stroke were evaluated in this study.

Methods

This was a prospective cohort study involving a hospital-based stroke registry; 1373 patients with acute ischemic stroke were enrolled. Patients were divided into the following four groups according their eGFR (calculated using the CKD Epidemiology Collaboration equations): ≥60, 45-59, 30-44, and <30 mL/min/1.73 m². The primary endpoint of poor functional outcome was defined as 3-month death or dependency (modified Rankin Scale score ≥3); secondary endpoints were neurological deterioration (increase in National Institutes of Health Stroke Severity score of ≥4 at discharge compared to baseline) during hospitalization and in-hospital mortality.

Results

The overall eGFR was 84.5±20.8 mL/min/1.73 m² (mean±SD). The distribution of baseline renal impairment was as follows: 1,218, 82, 40, and 33 patients had eGFRs of ≥60, 45-59, 30-44, and <30 mL/min/1.73 m², respectively. At 3 months after the stroke, 476 (34.7%) patients exhibited poor functional outcome. Furthermore, a poor functional outcome occurred more frequently with increasingly advanced stages of CKD (rates of 31.9%, 53.7%, 55.0%, and 63.6% for CKD stages 1/2, 3a, 3b, and 4/5, respectively; p<0.001). Multivariate analysis revealed that a baseline eGFR of <30 mL/min/1.73m² increased the risk of a poor functional outcome by 2.37-fold (p=0.047). In addition, baseline renal dysfunction was closely associated with neurological deterioration during hospitalization and with in-hospital mortality.

Conclusions

A low baseline eGFR was strongly predictive of both poor functional outcome at 3 months after ischemic stroke and neurological deterioration/mortality during hospitalization.

Reduced estimated glomerular filtration rate affects outcomes 3 months after intracerebral hemorrhage: the stroke acute management with urgent risk-factor assessment and improvement-intracerebral hemorrhage study

BACKGROUND

The effect of renal dysfunction on intracerebral hemorrhage (ICH) remains unclear. We investigated associations of renal dysfunction assessed by estimated glomerular filtration rate (eGFR) with clinical courses and outcomes in ICH patients.

METHODS

From a prospective, multicenter, observational study, 203 patients who had supratentorial ICH within 3 hours of onset were included. Patients were classified into 3 groups based on eGFR: Group 1 (eGFR < 60 mL/minute/m(2)), Group 2 (60-89), and Group 3 (≥ 90). Outcomes included neurologic deterioration within 72 hours, hematoma expansion (> 33% in volume) at 24 hours, and favorable (modified Rankin Scale [mRS] ≤ 2) or unfavorable (mRS ≥ 5) outcome at 3 months.

RESULTS

Thirty-seven patients (16 women, 74.6 ± 13.2 years) were assigned to Group 1, 99 (34 women, 65.2 ± 11.4 years) to Group 2, and 67 (30 women, 61.3 ± 9.4 years) to Group 3. Significant differences were found in age (P < .001) and initial systolic blood pressure among the groups (208.4 ± 18.0, 201.9 ± 15.1, and 198.1 ± 14.2 mm Hg for Group 1, 2, and 3, respectively; P = .006). Similar rates of neurologic deterioration (14%, 6%, and 6%) and hematoma expansion (16%, 14%, and 18%) were observed among the groups. However, in Group 1, favorable outcome was less frequent (17%, 48%, and 42%; P = .002) and unfavorable outcome was more frequent (24%, 7%, and 6%; P = .013) than in the other groups. After adjustment for confounders, eGFR < 60 mL/minute/m(2) was independently associated with both favorable outcome (odds ratio [OR], .21; 95% CI, .07-.54) and unfavorable outcome (OR, 5.64; 95% CI, 1.80-18.58).

CONCLUSIONS

Renal dysfunction (eGFR < 60 mL/minute/m(2)) was associated with poor clinical outcome after ICH.

Chronic kidney disease is an independent predictor of adverse clinical outcomes in patients with recent small subcortical infarcts

BACKGROUND

Chronic kidney disease (CKD) is associated with cerebral small vessel diseases (SVD) and predicts stroke, cardiovascular events and mortality. However, its association with recent small subcortical infarcts (RSSI), a novel subtype of cerebral SVD, has not yet been established in stroke patients. The aim of this longitudinal study was to clarify whether CKD can predict clinical outcome in patients with RSSI.

METHODS

We enrolled patients with first-ever RSSI (formerly categorized as acute lacunar stroke). CKD was defined as an estimated glomerular filtration rate of <60 ml/min/1.73 m(2) on admission. The patients were divided into two groups according to the presence or absence of CKD. The endpoints were recurrent stroke, cardiovascular events or all-cause mortality. The patients were followed up at 3, 6 and 12 months after stroke onset and yearly thereafter. Event-free survival analysis was undertaken using Kaplan-Meier plots and the log-rank test. Cox's proportional-hazards analysis was conducted regarding age, sex and the presence of any cerebral SVD.

RESULTS

A total of 152 patients (66% males; mean age: 67.6 years) were consecutively enrolled, and 44 (29%) had CKD. During the follow-up period (median: 3 years; interquartile range: 1-4), 27 patients (18%) reached endpoints. The numbers of patients per endpoint were as follows: all-cause mortality 14, ischemic stroke 9, hemorrhagic stroke 2 and aortic dissection 2. Patients with CKD were significantly older (77 vs. 64 years; p < 0.001), had higher serum creatinine (0.96 vs. 0.65 mg/dl; p < 0.001), higher brain natriuretic peptide (51.1 vs. 18.5 pg/ml; p < 0.001) and a higher National Institutes of Health Stroke Scale score on admission (3 vs. 2; p < 0.001), and were less likely to have modified Rankin Scale scores of 0-2 after stroke onset (52 vs. 77%; p = 0.003). Patients with white matter hyperintensity [odds ratio (OR) 3.0; 95% confidence interval (CI): 1.5-6.2; p = 0.003] and those with microbleeds (OR 2.5; 95% CI: 1.2-5.1; p = 0.015) had more pronounced CKD than the remaining patients. A Kaplan-Meier curve analysis showed that patients with CKD had a less favorable outcome than those without CKD (p < 0.001). The multivariate Cox proportional-hazards analysis revealed that CKD was associated with recurrent stroke, cardiovascular events or all-cause mortality (hazard ratio 2.22; 95% CI: 1.12-4.25; p = 0.02).

CONCLUSIONS

CKD was found to be independently associated with recurrent stroke, cardiovascular events or all-cause mortality in patients with RSSI.

Patterns of care quality and prognosis among hospitalized ischemic stroke patients with chronic kidney disease

Background

Relatively little is known about the quality of care and outcomes for hospitalized ischemic stroke patients with chronic kidney disease (CKD). We examined quality of care and in‐hospital prognoses among patients with CKD in the Get With The Guidelines–Stroke (GWTG‐Stroke) program

Methods and Results

We analyzed 679 827 patients hospitalized with ischemic stroke from 1564 US centers participating in the GWTG‐Stroke program between January 2009 and December 2012. Use of 7 predefined ischemic stroke performance measures, composite “defect‐free” care compliance, and in‐hospital mortality were examined based on glomerular filtration rate (GFR) categorized as a dichotomous (+CKD as <60) or rank‐ordered variable: normal (≥90), mild (≥60 to <90), moderate (≥30 to <60), severe (≥15 to <30), and kidney failure (<15 or dialysis). There were 236 662 (35%) ischemic stroke patients with CKD. Patients with severe renal dysfunction or failure were significantly less likely to receive guideline‐based therapies. Compared with patients with normal kidney function (≥90), those with CKD (adjusted OR 0.91 [95% CI: 0.89 to 0.92]), moderate dysfunction (adjusted OR 0.94 [95% CI: 0.92 to 0.97]), severe dysfunction (adjusted OR 0.80 [95% CI: 0.77 to 0.84]), or failure (adjusted OR 0.72 [95% CI: 0.68 to 0.0.76]), were less likely to receive 100% defect‐free care measure compliance. Inpatient mortality was higher for patients with CKD (adjusted odds ratio 1.44 [95% CI: 1.40 to 1.47]), and progressively rose with more severe renal dysfunction.

Conclusions

Despite higher in‐hospital mortality rates, ischemic stroke patients with CKD, especially those with greater severity of renal dysfunction, were less likely to receive important guideline‐recommended therapies.

Management of Atrial Fibrillation in Patients With Kidney Disease

The increasing burden of Chronic Kidney Disease (CKD) is highly relevant to cardiologists, as cardiovascular mortality is 10-30 times higher amongst people with End-stage Renal Disease (ESRD), comparing with general population. One of the commonest associations is the increased frequency of atrial fibrillation (AF) amongst those experiencing CKD. Overall, we know that AF is the most common cardiac arrhythmia. AF leads to a substantial risk of mortality and morbidity, from stroke and thromboembolism, heart failure, reduced cognitive function and impaired quality of life. However, most clinical trials in AF (for example, for stroke prevention in AF with anticoagulation therapy) have largely excluded patients with significant renal impairment. In this review article, we will focus on stroke prevention in AF, and the clinical impact of CKD and its implications for management.

Renal Dysfunction in Stroke Patients: A Hospital-Based Cohort Study and Systematic Review

Background and purpose

Renal dysfunction (i.e. a reduced estimated glomerular filtration rate, eGFR) is commonly found in hospitalized stroke patients but its associations with Patients' characteristics and outcome require further investigation.

Methods

We linked clinical data from stroke patients enrolled between 2005 and 2008 into two prospective hospital registers with routine laboratory eGFR data. The eGFR was calculated using the Modification of Diet in Renal Disease method and renal dysfunction was defined as <60 ml/min/1·73 m2. In addition we systematically reviewed studies investigating the association between eGFR and outcome after stroke.

Results

Of 2520 patients who had an eGFR measured on admission hospital, 805 (32%) had renal dysfunction. On multivariate analysis, renal dysfunction was significantly less likely in those with a predicted good outcome (OR 0·27, 95% CI 0·21, 0·36) based on the well-validated six simple variable model. After adjustment for other predictive factors, stroke patients with renal dysfunction were more likely to die in hospital compared with those without (odds ratio 1·59, 95% confidence intervals 1·26, 2·00). Of the 31 studies involving 41 896 participants included in the systematic review, 18 studies found that low eGFR was an independent predictor of death and 6 reported a significant association with death and disability.

Conclusion

Our findings suggest that renal dysfunction on admission is common and associated with poor outcomes over the first year. Further work is required to establish to what extent these associations are causal and whether treating impaired renal function improves outcomes.

Stroke and renal dysfunction

Stroke is the most frequent neurological disease and represents a continuously evolving medical and social problem. Chronic kidney disease (CKD) is also an important worldwide public health problem. Renal dysfunction carries a substantial risk of cardiovascular morbidity and mortality and an independent, graded association between renal function and cardiovascular events was found. In the last 15years the link between CKD and cerebrovascular disease has become more apparent. Patients with end stage renal disease treated with maintenance hemodialysis have a much higher incidence of stroke than the general population and stroke is one of the major causes of death in these patients. Nowadays ischemic subtype of stroke is present in approximately 70% of dialysis patients. In population based studies conflicting results have been reported about the association between stroke and CKD before replacement therapy. However, in high risk patients, defined by the presence of either cardiovascular disease or cardiovascular risk factors, different stages of CKD are clearly associated with subsequent stroke. In patients with stroke the exact prevalence of renal dysfunction is not known. Reported prevalence from a few published studies is up to 38% and it is higher than that in age-matched control groups. Furthermore, in patients suffering from stroke renal dysfunction is associated with short and long term mortality. The most effective treatment of stroke in patients with CKD is not known and further studies are needed.

Association between AKI and long-term renal and cardiovascular outcomes in United States veterans

BACKGROUND AND OBJECTIVES

AKI is associated with major adverse kidney events (MAKE): death, new dialysis, and worsened renal function. CKD (arising from worsened renal function) is associated with a higher risk of major adverse cardiac events (MACE): myocardial infarction (MI), stroke, and heart failure. Therefore, the study hypothesis was that veterans who develop AKI during hospitalization for an MI would be at higher risk of subsequent MACE and MAKE.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients in the Veterans Affairs (VA) database who had a discharge diagnosis with International Classification of Diseases, Ninth Revision, code of 584.xx (AKI) or 410.xx (MI) and were admitted to a VA facility from October 1999 through December 2005 were selected for analysis. Three groups of patients were created on the basis of the index admission diagnosis and serum creatinine values: AKI, MI, or MI with AKI. Patients with mean baseline estimated GFR<45 ml/min per 1.73 m(2) were excluded. The primary outcomes assessed were mortality, MAKE, and MACE during the study period (maximum of 6 years). The combination of MAKE and MACE-major adverse renocardiovascular events (MARCE)-was also assessed.

RESULTS

A total of 36,980 patients were available for analysis. Mean age±SD was 66.8±11.4 years. The most deaths occurred in the MI+AKI group (57.5%), and the fewest (32.3%) occurred in patients with an uncomplicated MI admission. In both the unadjusted and adjusted time-to-event analyses, patients with AKI and AKI+MI had worse MARCE outcomes than those who had MI alone (adjusted hazard ratios, 1.37 [95% confidence interval, 1.32 to 1.42] and 1.92 [1.86 to 1.99], respectively).

CONCLUSIONS

Veterans who develop AKI in the setting of MI have worse long-term outcomes than those with AKI or MI alone. Veterans with AKI alone have worse outcomes than those diagnosed with an MI in the absence of AKI.

Effects of low estimated glomerular filtration rate on outcomes after stroke: a hospital-based stroke registry in China

BACKGROUND AND PURPOSE

As uncertainty persists over the prognostic significance of low estimated glomerular filtration rate (eGFR) in acute stroke, the effects of low eGFR on death/disability amongst participants with acute stroke in China were determined.

METHODS

Nanjing First Hospital stroke registry was a prospective cohort study of stroke patients. Patients with acute stroke (brain infarction, intracerebral hemorrhage or subarachnoid hemorrhage) within 7 days of onset were recruited consecutively from 2004 to 2008. Baseline eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation. Outcomes were death/disability, defined by scores 3-6 on the modified Rankin Scale at 90 days.

RESULTS

A total of 1909 participants were included in the present analyses. Of them, 112 (5.9%) had baseline moderate to severe decrease in eGFR (G3b-4) and increasing risk of higher National Institutes of Health Stroke Scale (NIHSS) scores. Low eGFR was associated with increasing risk of death/disability at 90 days [G3b-4, odds ratio 2.58 (95% confidence interval 1.71-3.91); G3a, 1.86 (1.35-2.56); G2, 1.21 (0.96-1.52); P trend <0.001). However, the association was not statistically significant after adjustment for demographic and clinical factors including NIHSS scores.

CONCLUSIONS

There were no appreciable effects of low eGFR on death/disability at 90 days independent of other prognostic factors in Chinese patients with acute stroke.

CKD is associated with recurrent ischemia but not with hemorrhagic transformation in acute ischemic stroke patients

BACKGROUND

We investigated the associations of Recurrent Ischemic Stroke (RIS) and Hemorrhagic Transformation (HT) with CKD in acute ischemic stroke patients.

METHOD

The subjects were 160 patients, divided into two groups: with eGFR <60 mL/min/1.73 m2 (CKD), with eGFR ≥60 mL/min/1.73 m2 (without CKD).

RESULTS

Subjects having DM (p = 0.018), CKD (p = 0.025) and treated with ACEI/ARB (p = 0.039) revealed association with RIS. Regression analysis disclosed only CKD (p = 0.04). Carotid artery stenosis (p = 0.030) and serum calcium levels (p = 0.013) showed significant association with HT.

CONCLUSION

Our results disclosed that CKD could be a risk factor for RIS. There is no relation between CKD and HT.

Association of renal biomarkers with 3-month and 1-year outcomes among critically ill acute stroke patients

Background

The comparative relationships of widely recognized biomarkers of renal injury with short-term and long-term outcomes among critically ill acute stroke patients are unknown. We evaluated the impact of baseline albuminuria [urine albumin-creatinine ratio (UACR)≥30 mg/g] or low estimated glomerular filtration rate (eGFR<60 ml/min per 1.73 m²) on stroke patients admitted to the intensive care unit (ICU).

Methods

We reviewed data on consecutive stroke patients admitted to a hospital ICU in Taiwan from September 2007 to August 2010 and followed-up for 1 year. Baseline UACR was categorized into <30 mg/g (normal), 30–299 mg/g (microalbuminuria), and ≥300 mg/g (macroalbuminuria), while eGFR was divided into ≥60, 45–59, and <45 ml/min per 1.73 m². The outcome measure was death or disability at 3-month and 1-year after stroke onset, assessed by dichotomizing the modified Rankin Scale at 3–6 versus 0–2.

Results

Of 184 consecutive patients, 153 (83%) met study entry criteria. Mean age was 67.9 years and median admission NIHSS score was 16. Among the renal biomarkers, only macroalbuminuria was associated with poorer 3-month outcome (OR 8.44, 95% CI 1.38 to 51.74, P = 0.021) and 1-year outcome (OR 18.06, 95% CI 2.59 to 125.94, P = 0.003) after adjustment of relevant covariates. When ischemic and hemorrhagic stroke were analyzed separately, macroalbuminuria was associated with poorer 1-year outcome among ischemic (OR 17.10, 95% CI 1.04 to 280.07, P = 0.047) and hemorrhagic stroke patients (OR 1951.57, 95% CI 1.07 to 3561662.85, P = 0.048), respectively, after adjustment of relevant covariates and hematoma volume.

Conclusions

Presence of macroalbuminuria indicates poor 3-month and 1-year outcomes among critically ill acute stroke patients.

Chronic kidney disease predicts impaired membrane microviscosity of red blood cells in hypertensive and normotensive subjects

Current evidence indicates that abnormalities in physical properties of the cell membranes may be strongly linked to hypertension and other circulatory disorders. Recent studies have shown that chronic kidney disease (CKD) might be a risk factor for cardiovascular and cerebrovascular outcomes. The purpose of the present study was to examine the possible relationship between kidney function and membrane fluidity (a reciprocal value of membrane microviscosity) of red blood cells (RBCs) in hypertensive and normotensive subjects using an electron spin resonance (ESR) and spin-labeling method. The order parameter (S) for the ESR spin-label agent (5-nitroxide stearate) in RBC membranes was significantly higher in hypertensive subjects than in normotensive subjects, indicating that membrane fluidity was decreased in hypertension. The order parameter (S) of RBCs was inversely correlated with estimated glomerular filtration rate (eGFR), suggesting that a decreased eGFR value might be associated with reduced membrane fluidity of RBCs. Multivariate regression analysis also demonstrated that, after adjustment for general risk factors, eGFR might be a significant predictor of membrane fluidity of RBCs. The reduced levels of both membrane fluidity of RBCs and eGFR were associated with increased plasma 8-iso-prostaglandin F2α (an index of oxidative stress) and decreased plasma nitric oxide (NO)-metabolites, suggesting that kidney function could be a determinant of membrane microviscosity of RBCs, at least in part, via oxidative stress- and NO-dependent mechanisms. The ESR study suggests that CKD might have a close correlation with impaired rheologic behavior of RBCs and microcirculatory disorders in hypertensive subjects.

Outcomes after kidney transplantation of patients previously diagnosed with atrial fibrillation

Little is known about the prevalence and outcomes of patients with atrial fibrillation/flutter (AF) who receive a kidney transplant. We identified all patients who had >1 year of uninterrupted Medicare A+B coverage before receiving their first kidney transplant (1997-2009). The presence of pretransplant AF was ascertained from diagnosis codes in Medicare physician claims. We studied the posttransplant outcomes of death, all-cause graft failure, death-censored graft failure and stroke using multivariable Cox regression. Of 62 706 eligible first kidney transplant recipients studied, 3794 (6.4%) were diagnosed with AF prior to kidney transplant. Over a mean follow up of 4.9 years, 40.6% of AF patients and 24.9% without AF died. All-cause and death-censored graft failure were 46.8% and 16.5%, respectively, in the AF group and 36.4% and 19.5%, respectively, in those without AF. Ischemic stroke occurred in 2.8% of patients with and 1.6% of patients without AF. In patients with AF, multivariable-adjusted hazard ratios (95% confidence intervals) for death, graft failure, death-censored graft failure and ischemic stroke were 1.46 (1.38-1.54), 1.41 (1.34-1.48), 1.26 (1.15-1.37) and 1.36 (1.10-1.68), respectively. Pre-existing AF is associated with poor posttransplant outcomes. Special attention should be paid to AF in pretransplant evaluation, counseling and risk stratification of kidney transplant candidates.

Impact and interaction of low estimated GFR and B vitamin therapy on prognosis among ischemic stroke patients: the Vitamin Intervention for Stroke Prevention (VISP) trial

BACKGROUND

Low estimated glomerular filtration rate (eGFR) has been linked to higher risk of primary stroke, but little is known about the relation of low eGFR to recurrent vascular risk after stroke. B Vitamin therapy has been used to lower homocysteine levels, but its interaction with kidney function on future major vascular events has not been assessed. The objective of this study was to conduct a secondary analysis based on the Vitamin Intervention for Stroke Prevention (VISP) trial to clarify these issues.

STUDY DESIGN

In the VISP trial, patients with a prior ischemic stroke were randomly assigned to receive the high- or low-dose B vitamin therapy. The trial did not find a difference between randomly assigned groups. The present study is a secondary analysis of the VISP trial.

SETTING & PARTICIPANTS

We analyzed the database of a multicenter trial comprising 3,673 patients with recent ischemic stroke who were followed up for 2 years.

PREDICTOR

We subdivided the cohort based on eGFR into 6 groups (≥105, 90-104, 75-89, 60-74, 45-59, and <45 mL/min/1.73 m²) for the analyses and used eGFR of 60-74 mL/min/1.73 m² as the reference category. Low eGFR was defined as <45 mL/min/1.73 m².

OUTCOMES

The primary end point for this analysis was major vascular events, defined as the composite of nonfatal ischemic stroke, nonfatal myocardial infarction, and vascular death (whichever event came first). The secondary end point was recurrent ischemic stroke. Also, the effects of high-dose B vitamin treatment on future major vascular events according to baseline eGFR categories were analyzed and reported separately.

RESULTS

Mean baseline eGFR was 73.9 ± 21.8 (SD) mL/min/1.73 m². 471 major vascular events during an average of 20 months of follow-up, including 300 recurrent strokes, were recorded. Baseline low eGFR was associated with increased risk of major vascular events (HR, 1.83; 95% CI, 1.32-2.52; P < 0.001) and recurrent stroke (HR, 1.53; 95% CI, 1.01-2.32; P = 0.04) after adjustment for traditional vascular risk factors and homocysteine level. At baseline eGFR <45 mL/min/1.73 m², high-dose B vitamin therapy compared to low dose showed a trend of higher risk of future major vascular events (HR, 1.49; 95% CI, 0.95-2.34; P = 0.08). The overall P value for interaction between B vitamin dose and eGFR was not significant (P = 0.6).

LIMITATIONS

No data for albuminuria.

CONCLUSIONS

Low eGFR is associated with higher risk of future major vascular events and recurrent stroke after a recent ischemic stroke.

Low glomerular filtration rate increases hemorrhagic transformation in acute ischemic stroke

BACKGROUND

Decreased glomerular filtration rate (GFR) can increase the risk of bleeding tendency and hemorrhagic stroke. However, the relationship between the levels of GFR and hemorrhagic transformation (HT) after acute ischemic stroke is largely unknown. The aim of this study was to assess whether GFR level is associated with HT in acute ischemic stroke.

METHODS

We reviewed 770 consecutive patients with acute ischemic stroke within 7 days from September 2007 to February 2012 in a prospective stroke registry database. We calculated the patient's GFR using the Cockcroft-Gault equation, and divided them into 3 groups: ≥60, 30-59 and <30 ml/min/1.73 m(2). HTs were identified by follow-up computed tomography (CT) or magnetic resonance imaging, and were defined as (1) any degree of high density within the area of low attenuation of vascular territory on noncontrast brain CT, or (2) low-signal intensity area in gradient echo within high-signal intensity meaning acute infarct on diffusion-weighted imaging. Multivariable logistic regression analyses were used to estimate the risk of GFR for HT. Stratification analyses were done according to the presence of HT high risk factors: atrial fibrillation (AF), thrombolysis and large size infarction. Additional logistic regression model for symptomatic HTs was established with the same variables.

RESULTS

HTs were noted in 131 patients (17.0%) and symptomatic HTs in 63 patients (8.2%). In univariate analysis, HTs were more frequent in patients with AF (51.9 vs. 16.7%, p < 0.001) and large-size infarction (42.0 vs. 5.3%, p < 0.001). The risk of HT was associated with decreased GFR among 3 subgroups classified according to the value of estimated GFR: 49/394 (12.4%) in the GFR ≥60 group, 66/312 (21.2%) in the 30≤ GFR <59 group and 16/64 (25.0%) in the GFR <30 group (p = 0.002). We found a significant association between the GFR <30 group and HTs in acute ischemic stroke (OR 2.90; 95% CI 1.26-6.68, p = 0.012) after adjusting for other risk factors. Moreover, the incidence of HTs was higher in the subgroups without thrombolysis (OR 3.49; 95% CI 1.44-8.46) and without AF (OR 3.44; 95% CI 1.10-10.76). Decreased GFR also had a tendency of increasing symptomatic HTs (OR 2.39; 95% CI 0.72-7.94, p = 0.154).

CONCLUSIONS

Low levels of GFR are associated with a high risk of HT after acute ischemic stroke. Further studies are needed to elucidate whether HT in the patients with renal insufficiency are related to a worse outcome after acute ischemic stroke.