The impact of acute kidney injury on short-term survival in an Eastern European population with stroke

Prognostic value of blood urea nitrogen to serum albumin ratio for acute kidney injury and in-hospital mortality in intensive care unit patients with intracerebral haemorrhage: a retrospective cohort study using the MIMIC-IV database

OBJECTIVE

We sought to evaluate the prognostic ability of blood urea nitrogen to serum albumin ratio (BAR) for acute kidney injury (AKI) and in-hospital mortality in patients with intracerebral haemorrhage (ICH) in intensive care unit (ICU).

DESIGN

A retrospective cohort study using propensity score matching.

SETTING

ICU of Beth Israel Deaconess Medical Center.

PARTICIPANTS

The data of patients with ICH were obtained from the Medical Information Mart for Intensive Care IV (V.1.0) database. A total of 1510 patients with ICH were enrolled in our study.

MAIN OUTCOME AND MEASURE

The optimal threshold value of BAR is determined by the means of X-tile software (V.3.6.1) and the crude cohort was categorised into two groups on the foundation of the optimal cut-off BAR (6.0 mg/g). Propensity score matching and inverse probability of treatment weighting were performed to control for confounders. The predictive performance of BAR for AKI was tested using univariate and multivariate logistic regression analyses. Multivariate Cox regression analysis was used to investigate the association between BAR and in-hospital mortality.

RESULTS

The optimal cut-off value for BAR was 6.0 mg/g. After matching, multivariate logistic analysis showed that the high-BAR group had a significantly higher risk of AKI (OR, 2.60; 95% confidence index, 95% CI, 1.86 to 3.65, p<0.001). What's more, a higher BAR was also an independent risk factor for in-hospital mortality (HR, 2.84; 95% confidence index, 95% CI, 1.96 to 4.14, p<0.001) in terms of multivariate Cox regression analysis. These findings were further demonstrated in the validation cohort.

CONCLUSIONS

BAR is a promising and easily available biomarker that could serve as a prognostic predictor of AKI and in-hospital mortality in patients with ICH in the ICU.

Acute kidney injury in neurocritical patients: a retrospective cohort study

BACKGROUND /OBJECTIVE

Acute kidney injury (AKI) is a significant complication in critical care units (CCU). Non-neurological complications such as AKI are an independent predictor of poor clinical outcomes, with an increase in morbidity and mortality, financial costs, and worse functional recovery. This work aims to estimate the incidence of AKI and evaluate the risk factors and complications of AKI in neurocritical patients hospitalized in the CCU.

METHODS

A retrospective cohort study was conducted. Patients admitted to the neurocritical care unit between 2016 and 2018 with a stay longer than 48 h were retrospectively analyzed in regard to the incidence, risk factors, and outcomes of AKI.

RESULTS

The study population comprised 213 neurocritical patients. The incidence of AKI was 23.5%, with 58% KDIGO 1 and 2% requiring renal replacement therapy. AKI was an independent predictor of prolonged use of mechanical ventilation, cerebral edema, and mortality. Cerebral edema [OR 4.40 (95% CI 1.98-9.75) p < 0.001] and a change in chloride levels greater than 4 mmol/L at 48 h (OR 2.44 (95% CI 1.10-5.37) p = 0.027) were risk factors for developing AKI in the first 14 days of hospitalization.

CONCLUSION

There is a high incidence of AKI in neurocritical patients; it is associated with worse clinical outcomes regardless of the CCU admission etiology or AKI severity.

Dynamic nomogram for predicting acute kidney injury in patients with acute ischemic stroke: A retrospective study

Background

This study sought to develop and validate a dynamic nomogram chart to assess the risk of acute kidney injury (AKI) in patients with acute ischemic stroke (AIS).

Methods

These data were drawn from the Medical Information Mart for Intensive Care III (MIMIC-III) database, which collects 47 clinical indicators of patients after admission to the hospital. The primary outcome indicator was the occurrence of AKI within 48 h of intensive care unit (ICU) admission. Independent risk factors for AKI were screened from the training set using univariate and multifactorial logistic regression analyses. Multiple logistic regression models were developed, and nomograms were plotted and validated in an internal validation set. Based on the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) to estimate the performance of this nomogram.

Results

Nomogram indicators include blood urea nitrogen (BUN), creatinine, red blood cell distribution width (RDW), heart rate (HR), Oxford Acute Severity of Illness Score (OASIS), the history of congestive heart failure (CHF), the use of vancomycin, contrast agent, and mannitol. The predictive model displayed well discrimination with the area under the ROC curve values of 0.8529 and 0.8598 for the training set and the validator, respectively. Calibration curves revealed favorable concordance between the actual and predicted incidence of AKI (p > 0.05). DCA indicates the excellent net clinical benefit of nomogram in predicting AKI.

Conclusion

In summary, we explored the incidence of AKI in patients with AIS during ICU stay and developed a predictive model to help clinical decision-making.

The Role of the Monocyte-to-Lymphocyte Ratio in Acute Ischemic Stroke Patients with Acute Kidney Injury

Objective

The objective of the study was to determine if acute kidney injury (AKI) in patients with acute ischemic stroke was associated with the monocyte-to-lymphocyte ratio (MLR) assessed upon admission to the neurology intensive care unit (NICU) (AIS). We also looked into the MLR's function in predicting hospital mortality in AIS patients.

Methods

This retrospective analysis included 595 adult patients with AIS who were hospitalized to the NICU of the First Affiliated Hospital of South China between January 2017 and December 2019. Clinical signs and imaging studies were used to diagnose AIS. KDIGO criteria were used to define AKI. The ratio of monocytes to lymphocytes was used to compute MLR, the ratio of neutrophils to lymphocytes was used to calculate NLR, and the ratio of platelets to lymphocytes was used to calculate PLR.

Result

361 males and 234 women between the ages of 66.27 ± 12.05 years took part in the study. The individuals' MLR was 0.4729 ± 0.3461 and their neutrophil-to-lymphocyte ratio (NLR) was 8.18 ± 5.45. There were notable disparities in MLR and NLR between the AKI and non-AKI groups (p < 0.001). The link between MLR and AKI development risk was enhanced after adjustment, with respective cutoff values of 0.4581 and 9.26. For the MLR-based prediction of AKI incidence, the areas under the receiver-operating characteristic curves (AUCs) were 0.711 (95% CI: 0.663-0.758). And NLR-based prediction of AKI incidence the AUCs was (95% CI: 0.742-0826). Additionally, MLR was associated with a higher rate of in-hospital mortality (2.825, 95% confidence interval: 1.058, 7.545), whereas NLR was associated with a risk of in-hospital mortality of 1.085. (95 percent CI: 1.022, 1.151). An AUC of 0.745 (95% CI: 0.601-0.889, p = 0.026) was obtained for in-hospital mortality based on the MLR, whereas an AUC of 0.724 (95% CI: 0.531-0.916, p = 0.042) was obtained for in-hospital mortality based on the NLR.

Conclusion

MLR and neutrophil-to-lymphocyte ratio (NLR) were associated with a higher risk of AKI and in-hospital death in AIS patients.

Acute kidney injury without need for dialysis, incidence, its impact on long-term stroke survival and progression to chronic kidney disease

INTRODUCTION

Patients who had a stroke are at increased risk of sepsis, dehydration and fluctuations in blood pressure, which may result in acute kidney injury (AKI). The impact of AKI on long-term stroke survival has not been studied well.

OBJECTIVE

We aimed to identify incidence of AKI during acute stroke, follow-up period and its impact on long-term survival and development of chronic kidney disease (CKD).

DESIGN, SETTING AND PARTICIPANTS

Retrospective analysis of patients who had a stroke admitted at the rehabilitation facility in Changi General Hospital, Singapore, between June 2008 and May 2017, with median follow-up of 141 (95% CI 120 to 163) months.

OUTCOME MEASURES AND RESULTS OF UNIVARIATE ANALYSIS

Total 681 patients, median age (63.6) years, 173 (28%) died during follow-up. Elevated blood urea (3.02, 95% CI 2.17 to 4.22; p≤0.001) and creatinine (1.96, 95% CI 1.50 to 2.57; p≤0.001) during stroke affected survival adversely.Excluding patients with CKD, we analysed the remaining 617 patients. AKI was noted in 75 (12.15%) patients during the index admission, and it affected survival adversely (2.16, 95% CI 1.49 to 3.13; p<0.001). Of the patients with AKI, 21 of 75 (28%) progressed to CKD over a median follow-up of 40.7 months.

CONCLUSIONS

We found AKI during stroke admission was associated with increased mortality as compared with those without AKI on univariate analysis. AKI without need of renal replacement therapy was also associated with progression to CKD in this cohort. This suggests that patients with AKI need to have their renal function monitored longitudinally for development of CKD.

Association of acute kidney disease with the prognosis of ischemic stroke in the Third China National Stroke Registry

Background

Acute kidney disease (AKD) evolves a spectrum of acute and subacute kidney disease requiring a global strategy to address. The present study aimed to explore the impact of AKD on the prognosis of ischemic stroke.

Methods

The Third China National Stroke Registry (CNSR-III) was a nationwide registry of ischemic stroke or transient ischemic attack between August 2015 and March 2018. As a subgroup of CNSR-III, the patients who had serum creatinine (sCr) and serum cystatin C (sCysC) centrally tested on admission and at 3-month, and with 1-year follow-up data were enrolled. Modified AKD criteria were applied to identify patients with AKD during the first 3 months post stroke according to the guidelines developed by the Kidney Disease: Improving Global Outcomes in 2012. The primary clinical outcome was 1-year all-cause death, and secondary outcomes were stroke recurrence and post stroke disability.

Results

Five thousand sixty-five patients were recruited in the study. AKD was identified in 3.9%, 6.7%, 9.9% and 6.2% of the patients by using sCr, sCr-based estimated glomerular filtration rate (eGFR_sCr), sCysC-based eGFR (eGFR_sCysC), and combined sCr and sCysC-based eGFR (eGFR_sCr+sCysC) criteria, respectively. AKD defined as sCr or eGFR_sCr criteria significantly increased the risk of all-cause mortality (adjusted HR 2.67, 95% CI: 1.27–5.61; adjusted HR 2.19, 95% CI: 1.17–4.10) and post stroke disability (adjusted OR 1.60, 95% CI: 1.04–2.44; adjusted OR 1.51, 95% CI: 1.08–2.11). AKD diagnosed by eGFR_sCysC or eGFR_sCr+sCysC criteria had no significant impact on the risk of all-cause death and post stroke disability. AKD, defined by whichever criteria, was not associated with the risk of stroke recurrence in the adjusted model.

Conclusions

AKD, diagnosed by sCr or eGFR_sCr criteria, were independently associated with 1-year all-cause death and post stroke disability in Chinese ischemic stroke patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02817-4.

Machine learning for the prediction of acute kidney injury in critical care patients with acute cerebrovascular disease

Purpose

Acute kidney injury (AKI) is a common complication and associated with a poor clinical outcome. In this study, we developed and validated a model for predicting the risk of AKI through machine learning methods in critical care patients with acute cerebrovascular disease.

Methods

This study was a retrospective study based on two different cohorts. Five machine learning methods were used to develop AKI risk prediction models. We used six popular metrics (AUROC, F2-Score, accuracy, sensitivity, specificity and precision) to evaluate the performance of these models.

Results

We identified 2935 patients in the MIMIC-III database and 499 patients in our local database to develop and validate the AKI risk prediction model. The incidence of AKI in these two different cohorts was 18.3% and 61.7%, respectively. Analysis showed that several laboratory parameters (serum creatinine, hemoglobin, white blood cell count, bicarbonate, blood urea nitrogen, sodium, albumin, and platelet count), age, and length of hospital stay, were the top ten important factors associated with AKI. The analysis demonstrated that the XGBoost had higher AUROC (0.880, 95%CI: 0.831–0.929), indicating that the XGBoost model was better at predicting AKI risk in patients with acute cerebrovascular disease than other models.

Conclusions

This study developed machine learning methods to identify critically ill patients with acute cerebrovascular disease who are at a high risk of developing AKI. This result suggested that machine learning techniques had the potential to improve the prediction of AKI risk models in critical care.

Acute Kidney Injury at the Neurocritical Care Unit

Neurocritical care has advanced substantially in recent decades, allowing doctors to treat patients with more complicated conditions who require a multidisciplinary approach to achieve better clinical outcomes. In neurocritical patients, nonneurological complications such as acute kidney injury (AKI) are independent predictors of worse clinical outcomes. Different research groups have reported an AKI incidence of 11.6% and an incidence of stage 3 AKI, according to the Kidney Disease: Improving Global Outcomes, that requires dialysis of 3% to 12% in neurocritical patients. These patients tend to be younger, have less comorbidity, and have a different risk profile, given the diagnostic and therapeutic procedures they undergo. Trauma-induced AKI, sepsis, sympathetic overstimulation, tubular epitheliopathy, hyperchloremia, use of nephrotoxic drugs, and renal hypoperfusion are some of the causes of AKI in neurocritical patients. AKI is the result of a sum of events, although the mechanisms underlying many of them remain uncertain; however, two important causes that merit mention are direct alteration of the physiological brain-kidney connection and exposure to injury as a result of the specific medical management and well-established therapies that neurocritical patients are subjected to. This review will focus on AKI in neurocritical care patients. Specifically, it will discuss its epidemiology, causes, associated mechanisms, and relationship to the brain-kidney axis. Additionally, the use and risks of extracorporeal therapies in this group of patients will be reviewed.

Acute Kidney Injury in Acute Ischemic Stroke Patients in Clinical Trials

OBJECTIVES

Acute ischemic stroke patients are at risk of acute kidney injury due to volume depletion, contrast exposure, and preexisting comorbid diseases. We determined the occurrence rate and identified predictors associated with acute kidney injury in acute ischemic stroke patients.

SETTING

Multiple specialized ICUs within academic medical centers.

DESIGN

Post hoc analysis of pooled data from prospective randomized clinical trials.

PATIENTS

Acute ischemic stroke patients recruited within 3 hours or within 5 hours of symptom onset.

INTERVENTIONS

IV recombinant tissue plasminogen activator, endovascular treatment, IV albumin, or placebo.

MEASUREMENTS AND MAIN RESULTS

Serum creatinine levels from baseline and within day 5 or discharge were used to classify acute kidney injury classification into stages. Any increase in serum creatinine was seen in 697 (36.1%) and acute kidney injury was seen in 68 (3.5%) of 1,931 patients with acute ischemic stroke. Severity of acute kidney injury was grade I, II, and III in 3.1%, 0.4%, and 0.05% patients, respectively. Patients with albumin (5.5% compared with 2.6%; p = 0.001), preexisting hypertension (4.3% compared with 1.5%; p = 0.0041), and preexisting renal disease (9.1% compared with 3.0%; p < 0.0001) had higher risk of acute kidney injury. The risk of acute kidney injury was lower between those who either underwent CT angiography (2.0% compared with 4.7%; p = 0.0017) or endovascular treatment (1.6% compared with 4.2%; p = 0.0071). In the multivariate analysis, hypertension (odds ratio, 2.6; 95% CI, 1.2-5.6) and renal disease (odds ratio, 3.5; 95% CI, 1.9-6.5) were associated with acute kidney injury. The risk of death was significantly higher among patients with acute kidney injury (odds ratio, 2.7; 95% CI, 1.4-4.9) after adjusting for age and National Institutes of Health Stroke Scale score strata.

CONCLUSIONS

The occurrence rate of acute kidney injury in acute ischemic stroke patients was low and was not higher in patients who underwent CT angiogram or those who received endovascular treatment. Occurrence of acute kidney injury increased the risk of death within 3 months among acute ischemic stroke patients.

Factors Contributing to an Efficacious Endovascular Treatment for Acute Ischemic Stroke in Asian Population

Although randomized control trials about endovascular treatment (EVT) of emergent large vessel occlusion (LVO) have demonstrated the success of mechanical thrombectomy as the choice of treatment, a wide range of caveats remain unaddressed. Asian patients were rarely included in the trials, thereby raising the question of whether the treatment could be generalized. In addition, there remains a concern on the feasibility of the method with respect to its application against intracranial atherosclerosis (ICAS)-related LVO, frequently observed in the Asian population. It is important to include evidence on ICAS LVO from Asian countries in the future for a comprehensive understanding of LVO etiology. Besides the issues with EVT, prognostic concerns in diabetes patients, acute kidney injury following EVT, neuroprotective management against reperfusion injury, and other peri-EVT issues should be considered in clinical practice. In the current article, we present an in-depth review of the literature that revises information pertaining to such concerns.

Acute kidney injury in patients with malignant middle cerebral artery infarction undergoing hyperosmolar therapy with mannitol

PURPOSE

To assess the kidney safety profile of mannitol in patients with malignant middle cerebral artery (MCA) infarction.

MATERIAL AND METHODS

We studied consecutive patients with malignant MCA infarction (01/2008-01/2018). Malignant MCA infarction was defined according to DESTINY criteria. We compared clinical endpoints including acute kidney injury (AKI; according to Kidney Disease: Improving Global Outcomes [KDIGO]) and dialysis between patients with and without mannitol. Multivariable model was built to explore predictor variables of AKI and in-hospital death.

RESULTS

Overall, 219 patients with malignant MCA infarction were included. Mannitol was administered in 93/219 (42.5%) patients with an average dosage of 650 g (250-950 g). Patients treated with mannitol more frequently suffered from AKI (39.8% vs. 11.9%; p < 0.001) and required hemodialysis (7.5% vs. 0.8%; p = 0.01) than patients without mannitol. At discharge, more patients in the mannitol group had persistent AKI than control patients (23.7% vs. 6.4%, p < 0.001). In multivariable model, mannitol emerged as independent predictor of AKI (OR 5.02, 95%CI 2.36-10.69; p < 0.001).

CONCLUSIONS

Acute kidney injury appears to be a frequent complication of hyperosmolar therapy with mannitol in patients with malignant MCA infarction. Given the lack of evidence supporting effectiveness of mannitol in these patients, its routine use should be carefully considered.

Effect of Blood Pressure Variability on Outcomes in Emergency Patients with Intracranial Hemorrhage

Introduction

Patients with spontaneous intracranial hemorrhage (sICH) have high mortality and morbidity, which are associated with blood pressure variability. Additionally, blood pressure variability is associated with acute kidney injury (AKI) in critically ill patients, but its association with sICH patients in emergency departments (ED) is unclear. Our study investigated the association between blood pressure variability in the ED and the risk of developing AKI during sICH patients’ hospital stay.

Methods

We retrospectively analyzed patients with sICH, including those with subarachnoid and intraparenchymal hemorrhage, who were admitted from any ED and who received an external ventricular drain at our academic center. Patients were identified by the International Classification of Diseases, Ninth Revision (ICD-9). Outcomes were the development of AKI, mortality, and being discharged home. We performed multivariable logistic regressions to measure the association of clinical factors and interventions with outcomes.

Results

We analyzed the records of 259 patients: 71 (27%) patients developed AKI, and 59 (23%) patients died. Mean age (± standard deviation [SD]) was 58 (14) years, and 150 (58%) were female. Patients with AKI had significantly higher blood pressure variability than patients without AKI. Each millimeter of mercury increment in one component of blood pressure variability, SD in systolic blood pressure (SBP_SD), was significantly associated with 2% increased likelihood of developing AKI (odds ratio [OR] 1.02, 95% confidence interval [CI], 1.005–1.03, p = 0.007). Initiating nicardipine infusion in the ED (OR 0.35, 95% CI, 0.15–0.77, p = 0.01) was associated with lower odds of in-hospital mortality. No ED interventions or blood pressure variability components were associated with patients’ likelihood to be discharged home.

Conclusion

Our study suggests that greater SBP_SD during patients’ ED stay is associated with higher likelihood of AKI, while starting nicardipine infusion is associated with lower odds of in-hospital mortality. Further studies about interventions and outcomes of patients with sICH in the ED are needed to confirm our observations.

Acute kidney injury after a stroke: A PRISMA-compliant meta-analysis

BACKGROUND

The relationship between acute kidney injury (AKI) and stroke needs quantitative summary. Therefore, we analyzed the associations between AKI and stroke including the incidence, risk factors of AKI after stroke, and the influence of AKI after a stroke on prognosis of stroke.

METHODS

Articles published until November 2019 were searched based on the following databases: PubMed, Web of Science, EMBASE, Medline, and Google Scholar. We computed the following results [rates of AKI incidence after a stroke, odds ratios (ORs) or relative risks (RRs) estimates and the 95% confidence intervals (CIs) for the association between risk factors and AKI, ORs or RRs and the CIs for the association between AKI and outcomes after a stroke] by using STATA 13.0 software.

RESULTS

The study reported an overall incidence of AKI of 12% with a random-effects model. Additionally, the present study showed that higher National Institutes of Health Stroke Scale (NIHSS) score on admission and history of hypertension were associated with higher risk of AKI after stroke. Moreover, the study showed that AKI after stroke was associated with higher in-hospital mortality, higher 1-month mortality, higher long-term mortality, and poorer functional outcome.

CONCLUSIONS

Acute kidney injury appears to be a common complication after stroke and is related to increased mortality and disability in stroke. Additionally, high NIHSS score on admission and history of hypertension were the critical risk factors for the AKI after stroke. More large-scale studies should be made to explore AKI after stroke.

Risk factors for renal failure and short-term prognosis in patients with spontaneous intracerebral haemorrhage complicated by acute kidney injury

Background

Although acute kidney injury (AKI) is a known risk factor for adverse clinical outcomes in patients with spontaneous intracerebral haemorrhage (SICH), little is known about the predisposing factors that contribute to renal failure and short-term prognosis in the setting of SICH already complicated by AKI. In this study, we aimed to identify the renal failure factors in SICH patents with AKI.

Methods

Five hundred forty-three patients with SICH complicated by differential severities of AKI who were admitted to the First Affiliated Hospital of Fujian Medical University from January 2016 to December 2018 were retrospectively studied. Logistic regression and receiver operator characteristic (ROC) curve analysis were performed to determine the best predictive and discriminative variables. Multivariate Cox regression analysis was performed to identify prognostic factors for renal recovery.

Results

In the multivariable adjusted model, we found that hypernatremia, metabolic acidosis, elevated serum creatine kinase, hyperuricaemia, proteinuria, and the use of colloids and diuretics were all independent risk factors for the occurrence of stage 3 AKI in SICH patients. The area under the curve analysis indicated that hypernatremia and hyperuricaemia were predictive factors for stage 3 AKI, and the combination of these two parameters increased their predictability for stage 3 AKI. Kaplan-Meier survival curves revealed that the renal recovery rate in SICH patients with stages 1 and 2 AKI was significantly higher than that in SICH patients with stage 3 AKI. Multivariate Cox regression analysis suggested that hypernatremia and the occurrence of stage 3 AKI are predictors for poor short-term renal recovery.

Conclusions

These findings illustrate that hypernatremia and hyperuricaemia represent potential risk factors for the occurrence of stage 3 AKI in SICH patients. Those patients with hypernatremia and stage 3 AKI were associated with a poor short-term prognosis in renal recovery.

Predictors of clinical outcome among Thai patients with atrial fibrillation-associated acute ischemic stroke

OBJECTIVE

To investigate the predictors of 3-month death among an atrial fibrillation-associated acute ischemic stroke (AF-stroke).

METHODS

This retrospective cohort study was conducted at a university hospital in Thailand. Patients with AF-stroke admitted between 2012 and 2017 were enrolled into the study. Baseline characteristics, clinical presentations, complications, and outcomes measured by the modified Rankin scale were collected from electronic medical records. Predictors of death outcomes were analyzed by univariate and multivariate logistic regression analysis.

RESULTS

The mortality rate among 119 AF-stroke patients was 26.89%. The independent predictors of 3-month death were developing AKI during hospitalization (adjusted odds ratio [aOR] = 6.38, 95% CI = 1.96-20.76, p = 0.001) and age above 75 years old (aOR = 3.08, 95% CI = 1.17-8.13, p = 0.019). In contrast, receiving treatment with an oral anticoagulant prior to the stroke episode was a protective factor (aOR = 0.13, 95% CI = 0.03-0.64, p = 0.002).

CONCLUSION

Developing AKI and older age were the independent predictor of 3- month death among AF-stroke patients.

The impact of acute kidney injury on fatality of ischemic stroke from a hospital-based population in Joinville, Brazil

Introduction:

The occurrence of acute kidney injury (AKI) after ischemic stroke has been associated to a worse prognosis. There is a lack of Brazilian studies evaluating this issue. This study aimed to describe the impact of AKI after a first-ever ischemic stroke in relation to fatality rate in 30 days.

Methods:

This was a retrospective hospital-based cohort. We included patients who had their first ischemic stroke between January to December 2015. AKI was defined by an increase of serum creatinine in relation to baseline value at admission ≥ 0.3 mg/dL or a rise in serum creatinine level by 1.5 times the baseline value at any point in the first week after admission. We performed a univariate and multivariate analysis to evaluate the presence of AKI with fatality in 30 days.

Results:

The final study population (n=214) had mean age of 66.46 ± 13.73 years, 48.1% were men, the mean NIHSS was 6.33 ± 6.27 and 20 (9.3%) presented AKI. Patients with AKI were older, had a higher score on the NIHSS, and had higher creatinine values on hospital discharge. The 30-day mortality was higher in the AKI subgroup compared to non-AKI (35% vs. 6.2%, p < 0.001). AKI was an independent predictor of fatality after an ischemic stroke but limited by severity of stroke (NIHSS).

Conclusion:

The presence of AKI is an important complication after ischemic stroke. Despite its impact on 30-day fatality, the predictive strength of AKI was limited by the severity of stroke.

Acute kidney injury calculated using admission serum creatinine underestimates 30-day and 1-year mortality after acute stroke

BACKGROUND

Acute kidney injury (AKI) diagnosis requires ascertainment of change from a known baseline. Although pre-admission serum creatinine (SCr) is recommended, to date, all studies of AKI in acute stroke have used the first SCr on admission.

METHODS

All patients admitted with an acute stroke to an emergency hospital were recruited. We compared use of pre-admission SCr with admission SCr to diagnose AKI. Regression analyses were used to identify risk factors for 30-day and 1-year mortality, respectively.

RESULTS

A total of 1354 patients were recruited from December 2012 to September 2015. Incidence of AKI was 18.7 and 19.9% using pre-admission SCr and admission SCr, respectively. Diagnosis of AKI was associated with significantly increased 30-day and 1-year mortality. Diagnosis of AKI using pre-admission SCr had a stronger relationship with both 30-day and 1-year mortality. In 443 patients with a pre-admission SCr and at least two SCr during admission, AKI diagnosed using pre-admission SCr had a stronger relationship than AKI diagnosed using admission SCr with 30-day mortality [odds ratio (OR) = 2.64; 95% confidence interval (CI) 1.36-5.12; P = 0.004 versus OR = 2.10; 95% CI 1.09-4.03; P = 0.026] and 1-year mortality [hazard ratio (HR) = 1.90, 95% CI 1.32-2.76; P = 0.001 versus HR = 1.47; 95% CI 1.01-2.15; P = 0.046] in fully adjusted models.

CONCLUSIONS

AKI after stroke is common and is associated with increased 30-day and 1-year mortality. Using first SCr on admission gives a comparable AKI incidence to pre-admission SCr, but underestimates 30-day and 1-year mortality risk.

Under-recognized post-stroke acute kidney injury: risk factors and relevance for stroke outcome of a frequent comorbidity

BACKGROUND

Acute kidney injury (AKI) is emerging as a predictor of poor stroke outcome, however, it is often not recognized. The aim of our study was to evaluate post-stroke AKI burden, AKI risk factors and their influence in post-stroke outcome.

METHODS

From 2013 to 2016, 440 individuals with stroke diagnosis admitted in Stroke Unit, Foundation IRCCS Policlinico San Matteo (Pavia, Italy), were retrospectively enrolled. AKI cases identified by KDIGO criteria through the electronic database and hospital chart review were compared with the ones reported in discharge letters or in administrative hospital data base. Mortality data were provided by Agenzia Tutela della Salute of Pavia.

RESULTS

We included 430 patients in the analysis. Median follow-up was 19.2 months. We identified 79 AKI cases (18% of the enrolled patients, 92% classified as AKI stage 1), a fivefold higher number of cases than the ones reported at discharge. 37 patients had AKI at the admission in the hospital, while 42 developed AKI during the hospitalization. Cardioembolic (p = 0.01) and hemorrhagic (p = 0.01) stroke types were associated with higher AKI risk. Admission National Institutes of Health Stroke Scale (NIHSS, p < 0.05) and Charlson Comorbidity Index (p < 0.01) were independently associated with overall AKI, while admission NIHSS (p < 0.05) and eGFR (p < 0.005) were independently associated with AKI developed during the hospitalization. AKI was associated to longer in-hospital stay (p = 0.01), worse Rankin Neurologic Disability Score at discharge (p < 0.0001) and discharge disposition other than home (p = 0.03). AKI was also independently associated to higher in-hospital mortality (OR 3.9 95% CI 1.2-12.9 p = 0.023) but not with long-term survival.

CONCLUSIONS

Post-stroke AKI diagnosis needs to be improved by strictly monitoring individuals with cardioembolic or hemorrhagic stroke, reduced kidney function, higher Charlson Comorbidity Index and worse NIHSS at presentation.

Study on Acute Kidney Injury in Patients with Spontaneous Intracerebral Hemorrhage: an Overview from a Tertiary Care Hospital in South India

INTRODUCTION

Acute kidney injury (AKI) is an independent risk factor for adverse clinical outcomes in patients with hemorrhagic stroke. There is limited data regarding the occurrence and impact of AKI in the setting of spontaneous intracerebral hemorrhage (SICH). Considering this, we sought to determine the incidence and risk factors for AKI in patients with SICH and to determine the role of AKI on SICH mortality in our population.

MATERIALS AND METHODS

This is a retrospective analysis of the data recorded in the stroke registry maintained by the Department of Neurosurgery, Kasturba Hospital, Kasturba Medical College, Manipal Academy of Higher Education after ethical committee clearance. Information regarding clinical features, demographics, laboratory data, prescribing patterns, and the use of contrast-mediated imaging were collected. AKI was defined according to the Kidney Disease: Improving Global Outcomes criteria. Logistic multivariate regression was used to determine predictors of AKI. Analysis of variance was used to measure the effect of AKI on SICH outcome.

RESULTS

Of 316 patients with SICH admitted to the hospital, 20% of patients developed AKI. It was found that risk factors for AKI were lower baseline estimated glomerular filtration rate (odds ratio, 1.60; 95% confidence interval, 1.21 SICH 2.2; P < 0.001) and infectious complications (odds ratio, 3.37; 95% confidence interval, 1.9-5.7; P < 0.001). The incidence of 30 days' mortality was higher in the group with AKI (14% vs. 5.5%). There was a significant association between AKI severity and short-term mortality (P < 0.001). Patients with AKI had a lower Glasgow Coma Scale on admission (11.81 ± 3.17 vs. 10.83 ± 3.2) and discharge (12.44 ± 3.44 vs. 10.38 ± 3.2) compared to patients without AKI (P < 0.001). Greater severity of AKI was associated with worse neurologic outcome (P < 0.001).

DISCUSSION

Various studies in literature have evaluated the incidence of AKI after a stroke episode. The incidence of AKI was ranging from 8%-21% in those studies. In our study, we found that 20% of SICH patients developed AKI. The incidence of AKI in our study falls along the spectrum described in these previous studies.

CONCLUSIONS

AKI is a common complication of SICH. Lower estimated glomerular filtration rate at admission and infections were the significant risk factors. Patients with AKI had poor neurologic outcome and higher mortality and it increased with the severity of AKI.

Exosome-mediated amplification of endogenous brain repair mechanisms and brain and systemic organ interaction in modulating neurological outcome after stroke

Ischemic stroke is caused by a regional interruption of cerebral blood flow to the brain. Rigorous pre-clinical and clinical research has made landmark progress in stroke treatment using thrombolytics and endovascular thrombectomy. Although numerous successful neuroprotective therapeutic agents for ischemic stroke have been reported in pre-clinical studies, most of them failed in clinical testing. Persistent pre-clinical research has demonstrated that the ischemic brain is not only passively dying but is also actively recovering. Within the neurovascular niche in the peri-infarct tissue, repair mechanisms thrive on the interactions between the neural and vascular compartments. In this review, we discuss exogenous therapy using mesenchymal stromal cell-derived exosomes to amplify endogenous brain repair mechanisms and to induce neurorestorative effects after stroke. Emerging evidence indicates that multiple communication axes between the various organs such as the brain, heart, kidney and gut, and whole body immune response mediated by the spleen can also affect stroke outcome. Therefore, in this review, we summarize this evidence and initiate a discussion on the potential to improve stroke outcome by amplifying multiple brain repair mechanisms after stroke, and by targeting peripheral organs and downstream events to enhance recovery in the injured brain and promote over all well being.

Incidence and impact on outcomes of acute kidney injury after a stroke: a systematic review and meta-analysis

Background

Patients with chronic kidney disease have worse outcomes after stroke. However, the burden of acute kidney injury after stroke has not been extensively investigated.

Methods

We used MEDLINE and Embase to conduct a systematic review and meta-analysis of published studies that provided data on the risk of AKI and outcomes in adults after ischemic and hemorrhagic stroke. Pooled incidence was examined using the Stuart-Ord method in a DerSimonian-Laird model. Pooled Odds Ratios and 95% confidence intervals were calculated for outcomes using a random effects model. This review was registered with PROSPERO (CRD42017064588).

Results

Eight studies were included, five from the United States, representing 99.9% of included patients. Three studies used established acute kidney injury criteria based on creatinine values to define acute kidney injury and five used International Classification of Diseases coding definitions. Overall pooled incidence was 9.61% (95% confidence interval 8.33–10.98). Incidence for studies using creatinine definitions was 19.51% (95% confidence interval 12.75–27.32%) and for studies using coding definitions 4.63% (95% confidence interval 3.65–5.72%). Heterogeneity was high throughout. Mortality in stroke patients who sustained acute kidney injury was increased (Odds Ratio 2.45; 95% confidence interval 1.47–4.10). Three studies reported risk factors for acute kidney injury. There was sparse information on other outcomes.

Conclusions

Mortality in stroke patients who develop acute kidney injury is significantly increased. However the reported incidence of AKI after stroke varies widely and is underestimated using coding definitions. Larger international studies are required to identify potentially preventable factors to reduce acute kidney injury after stroke and improve outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1085-0) contains supplementary material, which is available to authorized users.

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.

Epidemiology of acute kidney injury in patients with stroke: a retrospective analysis from the neurology ICU

Acute kidney injury (AKI) is proven to be an independent risk factor for adverse clinical outcomes in patients with stroke, but data about the epidemiology of AKI in these patients are not well characterized. Therefore, we investigated the incidence, risk factors, and the impact of AKI on the clinical outcomes in a group of Chinese patients with stroke. We retrospectively recruited 647 stroke patients from the neurology ICU between 2012 and 2013. AKI was identified according to the 2012 KDIGO criteria. Baseline estimated glomerular filtration rate (eGFR) was calculated using modified Chronic Kidney Disease Epidemiology Collaboration equation for Chinese patients. National Institutes of Health Stroke Scale (NIHSS) score was assessed for the stroke severity. A total of 135 (20.9%) patients developed AKI. Patients with AKI stages from 1 to 3 were 84 (62.2%), 26 (19.3%), and 25 (18.5%), respectively. Logistic regression analysis showed that independent risk factors for AKI were higher NIHSS score (OR, 1.027; 95% CI 1.003-1.051), lower baseline eGFR (OR, 0.985; 95% CI 0.977-0.993), the presence of hypertension (OR, 1.592; 95% CI 1.003-2.529), and infectious complications (OR, 3.387; 95% CI 1.997-5.803) (P < 0.05 for all). AKI patients were also significantly associated with all-cause mortality in the neurology ICU [OR and 95% CI of AKI-stage 1, AKI-stage 2, and AKI-stage 3 were 4.961 (2.191-11.232), 19.722 (6.354-61.217), and 48.625 (17.616-134.222), respectively (P < 0.001 for all)]. AKI is common among patients with stroke and is associated with worse clinical outcomes after stroke. Prevention of AKI seems to be very important among these patients, because they are exposed to many risk factors for developing AKI.

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.

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.

[Causal relationships in stroke and kidney injury]

AIM

To assess the frequency, severity, and causes of acute kidney injury (AKI) in patients with stroke.

SUBJECTS AND METHODS

272 patients (143 men and 129 women) (mean age, 66.7±11.6 years) with stroke were examined. The 2008 European Stroke Organization (ESO) guidelines were used to diagnose stroke, to determine indications for and contraindications to thrombolytic therapy, and to evaluate its efficiency. Hemorrhagic and ischemic strokes (HS and IS) were diagnosed in 52 (19%) and 220 (81%) patients, respectively. AKI was diagnosed and classified according to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

RESULTS

AKI was diagnosed in 89 (33%) patients: 19 (36.5%) with HS and 70 (31.8%) with IS. The relative risk of death in patients with AKI-associated stroke was 2.6 (95% confidence interval (CI) 1.6-4.0). A poor outcome (the combined endpoint of death or Rankin scale scores of 4-5) was noted in 56 (62.9%) patients with AKI and in 70 (38.2 %) without AKI (χ2=14.6; p=0.0002). The relative risk of a poor outcome in patients with AKI-associated with stroke was 1.64 (95% CI 1.3-2.0). Forty-five (50.6%) patients with stroke developed AKI in the prehospital period.

CONCLUSION

AKI complicates stroke in every three patients and increases death rates. 50% of cases develop AKI in the prehospital period due to the common causes of stroke and AKI.

Incidence and Risk Factors for Acute Kidney Injury Following Mannitol Infusion in Patients With Acute Stroke: A Retrospective Cohort Study

Mannitol, an osmotic diuretic, is commonly used to treat patients with acute brain edema, but its use also increases the risk of developing acute kidney injury (AKI). In this study, we investigated the incidence and risk factors of mannitol-related AKI in acute stroke patients.A total of 432 patients (ischemic stroke 62.3%) >20 years of age who were admitted to the neurocritical care center in a tertiary hospital and received mannitol treatment were enrolled in this study. Clinical parameters including the scores of National Institutes of Health Stroke Scale (NIHSS) at admission, vascular risk factors, laboratory data, and concurrent nephrotoxic medications were registered. Acute kidney injury was defined as an absolute elevation in the serum creatinine (Scr) level of ≥0.3 mg/dL from the baseline or a ≥50% increase in Scr.The incidence of mannitol-related AKI was 6.5% (95% confidence interval, 4.5%-9.3%) in acute stroke patients, 6.3% in patients with ischemic stroke, and 6.7% in patients with intracerebral hemorrhage. Multivariate analysis revealed that diabetes, lower estimated glomerular filtration rate at baseline, higher initial NIHSS score, and concurrent use of diuretics increased the risk of mannitol-related AKI. When present, the combination of these elements displayed an area under the receiver operating characteristic curve of 0.839 (95% confidence interval, 0.770-0.909). In conclusion, mannitol-related AKI is not uncommon in the treatment of acute stroke patients, especially in those with vulnerable risk factors.

Correlation between Carotid Intima-Media Thickness and Early-Stage Chronic Kidney Disease: Results from Asymptomatic Polyvascular Abnormalities in Community Study

OBJECTIVE

Chronic kidney disease (CKD) might be a potential independent risk factor for increased carotid intima-media thickness (IMT). Our aim is to determine whether mild to moderate kidney dysfunction is associated with increased carotid IMT.

METHODS

We employed 3629 subjects free from clinical cardiovascular diseases at the baseline visit of the Asymptomatic Polyvascular Abnormalities in Community Study. Kidney function was evaluated in terms of estimated glomerular filtration rate (eGFR) calculated by the Chronic Kidney Disease Epidemiology Collaboration China equation. The mean of the maximal internal and common carotid IMT was measured by means of high-resolution B-mode ultrasound. Univariable linear regressions and multivariate logistic regressions were used to evaluate the independent association between kidney function and carotid IMT.

RESULTS

In the unadjusted linear analysis, carotid IMT showed a significant negative correlation with eGFR in both male (r = -.346, P < .001) and female (r = -.253, P < .001) subjects. After adjustment for age, traditional vascular risk factors (smoking, diabetes, systolic blood pressure, diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, and antihypertensive drug use), and nontraditional risk factors (C-reactive protein and homocysteine), the association remained significant. The odds ratio for increased IMT was 1.299 (95% confidence interval [CI], 1.062-1.588) in the group with an eGFR of 60-89 mL/minute/1.73 m(2) and 1.789 (95% CI, 1.203-2.660) in the group with an eGFR of 30-59 mL/minute/1.73 m(2).

CONCLUSIONS

Increased IMT is associated with early-stage CKD. This association is independent of traditional and nontraditional cardiovascular risk factors. Early detection of kidney dysfunction is important to improve risk stratification of atherosclerotic disease.

Acute renal failure worsens in-hospital outcomes in patients with intracerebral hemorrhage

BACKGROUND

Occurrence of acute renal failure (ARF) is more common in patients with intracerebral hemorrhage (ICH) compared with those with other stroke subtypes. We sought to determine the frequency and effect of ARF on in-hospital outcomes of patients with ICH.

METHODS

We analyzed data from all patients admitted to the United States' hospitals between 2005 and 2011 with the primary discharge diagnosis of ICH and secondary diagnosis of ARF. The associations of ARF with mortality and discharge outcomes in ICH patients were analyzed after adjusting for potential confounders using logistic regression analyses.

RESULTS

Of the 614,454 patients admitted with ICH, 41,694 (6.8%) had ARF. In-hospital dialysis was required in 700 (1.7%) patients. ICH patients with ARF had higher rates of moderate-to-severe disability (49.5% versus 44.2%; P < .0001) and in-hospital mortality (28.7% versus 22.4%; P < .0001) compared with those without ARF. After adjusting for age, gender, and potential confounders defined as statistically significant variables on univariate analysis, ICH patients with ARF had higher odds of moderate-to-severe disability (odds ratio [OR] 1.2; 95% confidence interval [CI], 1.1-1.3; P < .0001) and death (OR, 1.5; 95% CI, 1.4-1.6; P < .0001). The rates of moderate-to-severe disability and death were 37.5% and 50.2% among those who required dialysis, respectively.

CONCLUSIONS

In patients with ICH, ARF is associated with significantly higher rates of in-hospital mortality and moderate-to-severe disability at the time of discharge.

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.

Acute kidney injury and edaravone in acute ischemic stroke: the Fukuoka Stroke Registry

BACKGROUND

A free radical scavenger, edaravone, which has been used for the treatment of ischemic stroke, was reported to cause acute kidney injury (AKI) as a fatal adverse event. The aim of the present study was to clarify whether edaravone is associated with AKI in patients with acute ischemic stroke.

METHODS

From the Fukuoka Stroke Registry database, 5689 consecutive patients with acute ischemic stroke who were hospitalized within 24 hours of the onset of symptoms were included in this study. A logistic regression analysis for the Fukuoka Stroke Registry cohort was done to identify the predictors for AKI. A propensity score-matched nested case-control study was also performed to elucidate any association between AKI and edaravone.

RESULTS

Acute kidney injury occurred in 128 of 5689 patients (2.2%) with acute ischemic stroke. A multivariate analysis revealed that the stroke subtype, the basal serum creatinine level, and the presence of infectious complications on admission were each predictors of developing AKI. In contrast, a free radical scavenger, edaravone, reduced the risk of developing AKI (multivariate-adjusted odds ratio [OR] .45, 95% confidence interval [CI] .30-.67). Propensity score-matched case-control study confirmed that edaravone use was negatively associated with AKI (propensity score-adjusted OR .46, 95% CI .29-.74).

CONCLUSIONS

Although AKI has a significant impact on the clinical outcome of hospital inpatients, edaravone has a protective effect against the development of AKI in patients with acute 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.

Of heart and kidney: a complicated love story

The multiple connections that exist between the cardiovascular system and the kidney lead to a complex cardiovascular and renal medicine relationship. It is well established in the literature that chronic kidney disease (CKD) is an important and independent risk factor for cardiovascular disease (CVD). The prevalence of CKD in the general population is about 7%, comparable with the prevalence of diabetes. The main causes of CKD are diabetes and hypertension, worldwide. The prevalence of CVD in the CKD population ranges between 7 and 85% according to the CKD stage and type, and the patient diagnosed with CKD has a higher risk of dying of CVD than of starting renal replacement therapy. There are some particular aspects of CVD in CKD patients that differ from the general population, making its prevention and treatment a challenge for both cardiologists and nephrologists.

Epigenetic bystander-like effects of stroke in somatic organs

Clinical evidence suggests that stroke may lead to damage of somatic organs. This communication of damage is well- established in the case of exposure to genotoxic agents is termed a bystander effect. Genotoxic stress-induced bystander effects are epigenetically mediated. Here we investigated whether stroke causes epigenetic bystander-like effects in the liver, kidney and heart. We found a significant increase in the levels of H3K3 acetylation and H3K4 trimethylation, as well as a decrease in the H3K9 trimethylation in the kidney tissue of stroked rats. Furthermore, here we for the first time show changes in the gene and microRNA expression profile in the kidney tissues of stroked rats, as compared to intact control animals. Interestingly, the observed changes were somewhat similar to those reported earlier in kidney injury, inflammation, and acute renal failure. Our data explain the recent epidemiological evidence for the increased incidence of acute kidney injury post-stroke and provide an important roadmap for the future analysis of the mechanisms and cellular repercussions of the stroke-induced bystander-like effects in distal somatic organs.

Acute kidney injury is associated with increased hospital mortality after stroke

BACKGROUND

Acute kidney injury (AKI) is common and is associated with poor clinical outcomes. Information about the incidence of AKI and its effect on stroke outcomes is limited.

METHODS

Data were analyzed from a registry of subjects with ischemic stroke and intracerebral hemorrhage (ICH) hospitalized at a single academic medical center. Admission creatinine was considered to be the baseline. AKI was defined as a creatinine increase during hospitalization of 0.3 mg/dL or a percentage increase of at least 50% from baseline. Multivariate logistic regression models were created for both stroke types, with hospital mortality as the outcome. Covariates included gender, race, age, admission creatinine, National Institutes of Health Stroke Scale score at admission, the performance of a contrast-enhanced computed tomographic scan of the head and neck, and medical comorbidities.

RESULTS

There were 528 cases of ischemic stroke with 70 deaths (13%), and 829 cases of ICH with 268 deaths (32%). The mean age was 64 years; 56% of patients were men and 71% were white. AKI complicated 14% of ischemic stroke and 21% of ICH hospitalizations. In multivariate analysis stratified by stroke type, AKI was associated with increased hospital mortality from ischemic stroke (odds ratio [OR] 3.08; 95% confidence interval [CI] 1.49-6.35) but not ICH (OR 0.82; 95% CI 0.50-1.35), except for those surviving at least 2 days (OR 2.11; 95% CI 1.18-3.77).

CONCLUSIONS

AKI occurs frequently after stroke and is associated with increased hospital mortality. Additional studies are needed to establish if the association is causal and if measures to prevent AKI would result in decreased mortality.

Acute kidney injury in hospitalized HIV-infected patients: a cohort analysis

BACKGROUND

Acute kidney injury (AKI) in hospitalized human immunodeficiency virus (HIV)-infected patients in the highly active antiretroviral therapy (HAART) era has not been extensively addressed. The aim of the present study was to analyze the incidence, etiology, risk factors and the impact of AKI on in-hospital mortality in this population.

METHODS

A total of 489 HIV-infected patients hospitalized in the Department of Infectious Diseases of the Hospital de Santa Maria (Lisbon, Portugal) between January 2005 and December 2007 were retrospectively studied. AKI was defined by 'Risk Injury Failure Loss of kidney function End-stage kidney disease'(RIFLE) criteria based on serum creatinine. Comparisons between patients with and without AKI were performed using the Student's t-test or the χ2 test. Logistic regression method was used to determine predictors of AKI and in-hospital mortality. A two-tailed P-value <0.05 was considered significant.

RESULTS

Eighty-eight patients (18%) had AKI within the hospitalization period. The most common etiologies of AKI were sepsis (59%), nephrotoxic drug administration (37.5%), volume depletion (21.6%) and radiocontrast use (20.5%). Preexisting hypertension [adjusted odds ratio (OR) 2.4, 95% confidence interval (CI) 1.04-5.6, P = 0.04], acquired immunodeficiency syndrome (adjusted OR 2.7, 95% CI 1.2-6, P = 0.02), sepsis (adjusted OR 23, 95% CI 11-45.3, P < 0.001) and nephrotoxic drug administration (adjusted OR 2.8, 95% CI 1.4-5.8, P = 0.004) were risk factors of AKI. Patients with AKI had higher in-hospital mortality than patients without AKI (27.3 versus 8%, P < 0.001). In multivariate analysis, AKI was a risk factor of in-hospital mortality (adjusted OR 2.7, 95% CI 1.3-5.6, P = 0.008).

CONCLUSION

AKI occurred in 18% of hospitalized HIV-infected patients and it was independently associated with increased in-hospital mortality.

Effect of angiotensin II type 1 receptor blocker, candesartan, and beta 1 adrenoceptor blocker, atenolol, on brain damage in ischemic stroke

This work aims at studying the possible alteration of renal renin secretion after human ischemic stroke and correlating it to the post stroke neurological and renal function alterations using angiotensin II type 1(AT1) receptor blocker (ARB), candesartan, and beta 1 adrenoreceptor blocker atenolol, which inhibits renin secretion, in Wistar rats subjected to middle cerebral artery occlusion. Methods . This study comprised 21 patients with cerebral ischemic stroke. Seventeen normal persons were used for comparison. Recumbent and standing plasma renin activity (PRA), reflex plasma renin sensitivity, plasminogen activator inhibitor and creatinine clearance (Ccr) were estimated at admission and two weeks later. Moreover, 60 male Wistar rats were divided into two groups SHAM and ischemic. Each of the two groups was further subdivided into three subgroups, non-treated, atenolol treated, and candesartan treated. In all rats, mean arterial blood pressure (MAP), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), heart rate (HR), neurobehavioral evaluation, Ccr, PRA, and infarct size were measured. Results . Together with the significant deterioration of the neurological score, focal cerebral ischemia in rats resulted in increased PRA and decreased glomerular filtration rate (GFR). In ischemic stroke patients, GFR was significantly decreased at admission and two weeks later, PRA increased at admission and two weeks later while plasma renin reflex secretion sensitivity had decreased significantly at admission relative to controls, but it increased significantly 2 weeks later. Atenolol caused significant improvement of the neurobehavioral score and renal function and decrease infarct size of rats subjected to focal cerebral ischemia whereas candesartan caused significant improvement of the neurobehavioral score and decreased infarct size with no significant change in GFR. Neither atenolol nor candesartan caused significant change in MAP, SBP, DBP, PP and HR Conclusion . (1) Ischemic stroke seems to be associated with a postischemic increase of the plasma renin secretion, which may increase the infarct size in the brain and may induce acute renal insufficiency. (2) This study confirms that Atenolol and ARBs could benefit ischemic stroke patients without altering blood pressure.