The Albumin in Acute Stroke Part 1 Trial: an exploratory efficacy analysis

Association between lower neutrophil-to-albumin ratio and early neurological improvement in patients with acute cerebral infarction after intravenous thrombolysis

Elevated neutrophil counts and decreased albumin levels have been linked to an unfavorable prognosis in acute cerebral infarction (ACI). The objective of this study is to explore the correlation between the neutrophil-to-albumin ratio (NAR) and the early neurological improvement (ENI) of ACI patients following intravenous thrombolysis (IVT). ACI patients who underwent IVT between June 2019 and June 2023 were enrolled. The severity of ACI was assessed using the National Institutes of Health Stroke Scale (NIHSS). ENI was defined as a reduction in NIHSS score of ≥ 4 or complete resolution of neurological deficit within 24 h after IVT. Propensity score match (PSM) and logistic regression analysis were used to explore the correlation between these variables and the early neurological outcomes of patients. A total of 545 ACI patients were included, with 253 (46.4 %) experiencing ENI. Among the 193 pairs of patients after PSM, there was a significant association between NAR and ENI (OR, 0.89; 95 % CI, 0.85-0.94; p < 0.001). The restricted cubic splines analysis revealed a significant nonlinear correlation between NAR and ENI (p for nonlinear = 0.0004; p for overall = 0.0002). The optimal cutoff for predicting ENI was determined as a NAR level of 10.20, with sensitivity and specificity values of 73.6 % and 60.9 %. NAR levels are associated with ENI in ACI patients after IVT. The decreased levels of NAR indicate an increased likelihood of post-thrombolysis ENI in ACI patients.

Albumin Levels and Risk of Early Cardiovascular Complications After Ischemic Stroke: A Propensity-Matched Analysis of a Global Federated Health Network

BACKGROUND

No studies have investigated the association between albumin levels and the risk of early cardiovascular complications in patients with ischemic stroke.

METHODS

Retrospective analysis with a federated research network (TriNetX) based on electronic medical records (International Classification of Diseases-Tenth Revision-Clinical Modification and logical observation identifiers names and codes) mainly reported between 2000 and 2023, from 80 health care organizations in the United States. Based on albumin levels measured at admission to the hospital, patients with ischemic stroke were categorized into 2 groups: (1) reduced (≤3.4 g/dL) and (2) normal (≥3.5 g/dL) albumin levels. The primary outcome was a composite of all-cause death, heart failure, atrial fibrillation, ventricular arrhythmias, myocardial infarction, and Takotsubo cardiomyopathy 30 days from the stroke. Secondary outcomes were the risk for each component of the primary outcome. Cox regression analyses were used to calculate hazard ratios (HRs) and 95% CIs following propensity score matching.

RESULTS

Overall, 320 111 patients with stroke had normal albumin levels (70.9±14.7 years; 48.9% females) and 183 729 (57.4%) had reduced albumin levels (72.9±14.3 years; 50.3% females). After propensity score matching, the primary outcomes occurred in 36.0% of patients with reduced and 26.1% with normal albumin levels (HR, 1.48 [95% CI, 1.46-1.50]). The higher risk in patients with reduced albumin levels was consistent also for all-cause death (HR, 2.77 [95% CI, 2.70-2.84]), heart failure (HR, 1.31 [95% CI, 1.29-1.34]), atrial fibrillation (HR, 1.11 [95% CI, 1.09-1.13]), ventricular arrhythmias (HR, 1.38 [95% CI, 1.30-1.46]), myocardial infarction (HR, 1.60 [95% CI, 1.54-1.65]), and Takotsubo cardiomyopathy (HR, 1.51 [95% CI, 1.26-1.82]). The association between albumin levels and the risk of cardiovascular events was independent of advanced age, sex, multimorbidity, and other causes of hypoalbuminemia. A progressively increased risk of adverse events was found in patients with mild and severe reduced compared to normal albumin levels.

CONCLUSIONS

Albumin levels are associated with the risk of early cardiovascular events and death in patients with ischemic stroke. The potential pathophysiological or therapeutic roles of albumin in patients with stroke warrant further investigation.

Acute albumin administration as therapy for intracerebral hemorrhage: A literature review

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality. Secondary brain injury after surviving the initial ictus leads to severe neurological deficits, and has emerged as an attractive therapeutic target. Human serum albumin (HSA), a pluripotent protein synthesized mainly in the liver, has shown remarkable efficacy by targeting secondary brain injury pathways in rodent models of ICH, while results from relevant clinical research on albumin therapy remain unclear. Preclinical studies have shown albumin-mediated neuroprotection may stem from its biological functions, including its major antioxidation activity, anti-inflammatory responses, and anti-apoptosis. HSA treatment provides neuroprotective and recovery enhancement effects via improving short and long-term neurologic function, maintaining blood-brain barrier (BBB) integrity and reducing neuronal oxidative stress and apoptosis. Retrospective clinical studies have shown that admission hypoalbuminemia is a prognostic factor for poor outcomes in patients with ICH. However, clinical trial was terminated due to poor enrollment and its potential adverse effects. This review provides an overview of the physiological properties of albumin, as well as its potential neuroprotective and prognostic value and the resulting clinical implications.

Optimal Randomization Designs for Large Multicenter Clinical Trials: From the National Institutes of Health Stroke Trials Network Funded by National Institutes of Health/National Institute of Neurological Disorders and Stroke Experience

From 2016 to 2021, the National Institutes of Health Stroke Trials Network funded by National Institutes of Health/National Institute of Neurological Disorders and Stroke initiated ten multicenter randomized controlled clinical trials. Optimal subject randomization designs are demanded with 4 critical properties: (1) protection of treatment assignment randomness, (2) achievement of the desired treatment allocation ratio, (3) balancing of baseline covariates, and (4) ease of implementation. For acute stroke trials, it is necessary to minimize the time between eligibility assessment and treatment initiation. This article reviews the randomization designs for 3 trials currently enrolling in Stroke Trials Network funded by National Institutes of Health/National Institute of Neurological Disorders and Stroke, the SATURN (Statins in Intracerebral Hemorrhage Trial), the MOST (Multiarm Optimization of Stroke Thrombolysis Trial), and the FASTEST (Recombinant Factor VIIa for Hemorrhagic Stroke Trial). Randomization methods utilized in these trials include minimal sufficient balance, block urn design, big stick design, and step-forward randomization. Their advantages and limitations are reviewed and compared with traditional stratified permuted block design and minimization.

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

Early hyperchloremia and outcomes after acute ischemic stroke

OBJECTIVE

Based on the relationship between hyperchloremia and mortality in critically ill patients, we investigated the effect of early hyperchloremia on 90-day outcomes in acute ischemic stroke patients.

MATERIALS AND METHODS

Acute ischemic stroke patients recruited within 5 h of symptom onset were analyzed. Hyperchloremia (defined as 110 mmol/L or greater) at either baseline, or 24, or 48 h after randomization was identified and classified as one occurrence or two or more occurrences. Logistic regression analyses were performed to determine the effects of hyperchloremia on: favorable outcomes (defined by a National Institutes of Health Stroke Scale and/or modified Rankin scale scores of 0-1) at 90-day, death or disability at 90-day, and death within 90-day after accounting for potential confounders.

RESULTS

Among the total of 1275 patients, one and two or more occurrence of hyperchloremia within 48 h were seen in 191 patients and 108 patients, respectively. Compared with patients without hyperchloremia, patients with two or more occurrences of hyperchloremia at significantly higher odds of lack of favorable outcomes (odds ratio 3.0, 95% confidence interval 1.8-5.1) and death or disability (odds ratio 2.6, 95% confidence interval 1.6-4.1) at 90-day after adjustment for age, National Institutes of Health Stroke Scale score strata (6-9, 10-19, ≥ 20), study intervention, initial SBP, and intra-arterial treatment.

CONCLUSIONS

The independent association between sustained hyperchloremia and lack of favorable outcomes at 90-day suggest that avoidance of hyperchloremia may reduce the rate of lack of favorable outcomes and death or disability in patients with acute ischemic stroke.

Adjunctive cytoprotective therapies in acute ischemic stroke: a systematic review

With the introduction of endovascular thrombectomy (EVT), a new era for treatment of acute ischemic stroke (AIS) has arrived. However, despite the much larger recanalization rate as compared to thrombolysis alone, final outcome remains far from ideal. This raises the question if some of the previously tested neuroprotective drugs warrant re-evaluation, since these compounds were all tested in studies where large-vessel recanalization was rarely achieved in the acute phase. This review provides an overview of compounds tested in clinical AIS trials and gives insight into which of these drugs warrant a re-evaluation as an add-on therapy for AIS in the era of EVT. A literature search was performed using the search terms "ischemic stroke brain" in title/abstract, and additional filters. After exclusion of papers using pre-defined selection criteria, a total of 89 trials were eligible for review which reported on 56 unique compounds. Trial compounds were divided into 6 categories based on their perceived mode of action: systemic haemodynamics, excitotoxicity, neuro-inflammation, blood-brain barrier and vasogenic edema, oxidative and nitrosative stress, neurogenesis/-regeneration and -recovery. Main trial outcomes and safety issues are summarized and promising compounds for re-evaluation are highlighted. Looking at group effect, drugs intervening with oxidative and nitrosative stress and neurogenesis/-regeneration and -recovery appear to have a favourable safety profile and show the most promising results regarding efficacy. Finally, possible theories behind individual and group effects are discussed and recommendation for promising treatment strategies are described.

Albumin therapy for acute ischemic stroke: a meta-analysis

Human serum albumin has shown remarkable efficacy in rodent models of ischemic stroke, while results from relevant clinical research on albumin therapy remain controversial. We conducted a meta-analysis of published studies to quantitatively analyze the neurofunctional outcomes of patients with ischemic stroke treated with albumin. PubMed, Embase, and Cochrane Library were searched in July 2020. A total of four studies and 1611 patients were included. The aggregated results indicated that there were 635 patients with good neurological outcomes, among which 321 patients were in the albumin group (39.8%) and 314 patients in the control group (39.1%), showing no statistically significant difference between the albumin and control groups (OR = 1.04, 95% CI 0.85-1.27). The results suggest that albumin therapy at the acute stage of ischemic stroke has no beneficial effect on the long-term neurological function of patients with ischemic stroke. Considering pulmonary edema and other complications are more likely to occur in such patients after albumin infusion, the administration of albumin therapy for acute ischemic stroke should be done with utmost caution.

Frequency of Hypoalbuminemia and In-Hospital Mortality in Acute Ischemic Stroke Patients Presenting at a Tertiary Care Hospital, Hyderabad

Background The aim of this study was to determine the frequency of hypoalbuminemia and in-hospital mortality in acute ischemic stroke patients at a tertiary care hospital in Hyderabad. Methodology This was a prospective observational study conducted at the Department of Medicine, Isra University Hospital, Hyderabad, from February 17, 2017 to August 18, 2017. A total of 196 consecutive cases of acute ischemic stroke were included. Hypoalbuminemia was defined as serum albumin of <3.5 mg/dL. In-hospital outcome in terms of survival or death within seven days of admission was assessed and recorded. Data were analyzed using SPSS, version 20.0. (IBM Corp., Armonk, NY, US). Chi-square test was applied, and p-value of ≤0.05 was considered significant. Results Out of the 196 acute ischemic stroke cases, 146 (74.5%) were males and 50 (25.5%) were females. The mean age was 49.31 ± 10.46 years. A total of 90 (45.9%) cases had hypoalbuminemia. Out of these 196 cases, 22 (11.2%) expired within seven days of presentation of acute ischemic stroke, and out of these 22 expired cases, 18 (81.8%) had hypoalbuminemia. In-hospital mortality was found to be strongly associated with hypoalbuminemia (p < 0.001). Conclusions Frequency of hypoalbuminemia was significantly higher in ischemic stroke patients and was found to be associated with in-hospital mortality, warranting monitoring at regular intervals, as well as recognizing and treating it early for risk stratification.

Applying density-based outlier identifications using multiple datasets for validation of stroke clinical outcomes

INTRODUCTION

Clinicians commonly use the modified Rankin Scale (mRS) and the Barthel Index (BI) to measure clinical outcome after stroke. These are potential targets in machine learning models for stroke outcome prediction. Therefore, the quality of the measurements is crucial for training and validation of these models. The objective of this study was to apply and evaluate density-based outlier detection methods for identifying potentially incorrect measurements in multiple large stroke datasets to assess the measurement quality.

METHOD

We applied three density-based outlier detection methods including density-based spatial clustering of applications (DBSCAN), hierarchical DBSCAN (HDBSCAN) and local outlier factor (LOF) based on a large dataset obtained from a nationwide prospective stroke registry in Taiwan. The testing of each method was done by using four different NINDS funded stroke datasets.

RESULT

The DBSCAN achieved a high performance across all mRS values where the highest average accuracy was 99.2 ± 0.7 at mRS of 4 and the lowest average accuracy was 92.0 ± 4.6 at mRS of 3. The LOF also achieved similar performance, however, the HDBSCAN with default parameters setting required further tuning improvement.

CONCLUSION

The density-based outlier detection methods were proven to be promising for validation of stroke outcome measures. The outlier detection algorithm developed from a large prospective registry dataset was effectively applied in four different NINDS stroke datasets with high performance results. The tool developed from this detection algorithm can be further applied to real world datasets to increase the data quality in stroke outcome measures.

Intensive vs Standard Treatment of Hyperglycemia and Functional Outcome in Patients With Acute Ischemic Stroke: The SHINE Randomized Clinical Trial

IMPORTANCE

Hyperglycemia during acute ischemic stroke is common and is associated with worse outcomes. The efficacy of intensive treatment of hyperglycemia in this setting remains unknown.

OBJECTIVES

To determine the efficacy of intensive treatment of hyperglycemia during acute ischemic stroke.

DESIGN, SETTING, AND PARTICIPANTS

The Stroke Hyperglycemia Insulin Network Effort (SHINE) randomized clinical trial included adult patients with hyperglycemia (glucose concentration of >110 mg/dL if had diabetes or ≥150 mg/dL if did not have diabetes) and acute ischemic stroke who were enrolled within 12 hours from stroke onset at 63 US sites between April 2012 and August 2018; follow-up ended in November 2018. The trial included 1151 patients who met eligibility criteria.

INTERVENTIONS

Patients were randomized to receive continuous intravenous insulin using a computerized decision support tool (target blood glucose concentration of 80-130 mg/dL [4.4-7.2 mmol/L]; intensive treatment group: n = 581) or insulin on a sliding scale that was administered subcutaneously (target blood glucose concentration of 80-179 mg/dL [4.4-9.9 mmol/L]; standard treatment group: n = 570) for up to 72 hours.

MAIN OUTCOMES AND MEASURES

The primary efficacy outcome was the proportion of patients with a favorable outcome based on the 90-day modified Rankin Scale score (a global stroke disability scale ranging from 0 [no symptoms or completely recovered] to 6 [death]) that was adjusted for baseline stroke severity.

RESULTS

Among 1151 patients who were randomized (mean age, 66 years [SD, 13.1 years]; 529 [46%] women, 920 [80%] with diabetes), 1118 (97%) completed the trial. Enrollment was stopped for futility based on prespecified interim analysis criteria. During treatment, the mean blood glucose level was 118 mg/dL (6.6 mmol/L) in the intensive treatment group and 179 mg/dL (9.9 mmol/L) in the standard treatment group. A favorable outcome occurred in 119 of 581 patients (20.5%) in the intensive treatment group and in 123 of 570 patients (21.6%) in the standard treatment group (adjusted relative risk, 0.97 [95% CI, 0.87 to 1.08], P = .55; unadjusted risk difference, -0.83% [95% CI, -5.72% to 4.06%]). Treatment was stopped early for hypoglycemia or other adverse events in 65 of 581 patients (11.2%) in the intensive treatment group and in 18 of 570 patients (3.2%) in the standard treatment group. Severe hypoglycemia occurred only among patients in the intensive treatment group (15/581 [2.6%]; risk difference, 2.58% [95% CI, 1.29% to 3.87%]).

CONCLUSIONS AND RELEVANCE

Among patients with acute ischemic stroke and hyperglycemia, treatment with intensive vs standard glucose control for up to 72 hours did not result in a significant difference in favorable functional outcome at 90 days. These findings do not support using intensive glucose control in this setting.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01369069.

Handling of Missing Outcome Data in Acute Stroke Trials: Advantages of Multiple Imputation Using Baseline and Postbaseline Variables

BACKGROUND

In acute stroke randomized trials, missingness of final functional outcome data reduces study power and potentially biases findings of treatment effect. Best methods for handling missing outcome data have not been well delineated for diseases with monophasic onset and subsequent improvement, like acute stroke.

METHODS

We simulated data missingness in the public dataset of the landmark, second NINDS-tPA trial, by randomly removing 5%-25% of actual values for the 3-month modified Rankin Scale (mRS) of global disability. We evaluated 5 missing data-handling methods: complete case analysis (CCA), worst case imputation (WCI), last observation carried forward (LOCF), multiple imputation using baseline covariates only (MI-B), and multiple imputation using baseline and postbaseline observations (MI-BP).

RESULTS

With the original trial's 333 patients, tissue plasminogen activator was associated with 3-month disability benefit, both for mRS dichotomized at 0-1 (P = .014) and shift analysis (P = .035). Distance (root mean square error) of imputed from actual mRS values was best for LOCF (1.17) and MI-BP (1.28), intermediate for MI-B (1.89) and worst for WCI (3.77). Directional bias (mean difference) was least for MI-BP (.01) and MI-B (-.16), intermediate for LOCF (-.37), and worst for WCI (-3.22). Preservation of formally positive results was greatest for MI-BP and LOCF (preserved at all missingness rates), intermediate for CCA and MI-B (preserved only with missingness <10%-20%), and least for WCI (preserved only with missingness <5%-20%).

CONCLUSIONS

For acute stroke trials, multiple imputation using baseline and postbaseline observations is an advantageous approach to missing outcome data-handling, yielding high accuracy, reduced directional bias, and greater preservation of study power.

Fixed Dose IV rt-PA and Clinical Outcome in Ischemic Stroke Patients With Body Weight >100 kg: Pooled Data From 3 Randomized Clinical Trials

BACKGROUND AND PURPOSE

The ASA/AHA guidelines recommend a fixed dose of 90 mg of intravenous (IV) recombinant tissue plasminogen activator (rt-PA) for acute stroke patients weighing more than 100 kg. We aimed to determine if body weight >100 kg (and receiving <0.9 mg/kg dose) independently influence patient clinical outcomes following IV rt-PA treatment.

METHODS

We pooled data from IV rt-PA treatment arms from 3 randomized controlled clinical trials; NINDS IV rt-PA study, Interventional Management of Stroke 3 and ALIAS (part 1 and 2). Baseline characteristic, hospital course and 90-day mRS were compared between patients >100 kg and those ≤100 kg body weight. Multivariate logistic regression model was used to identify the independent effect of >100 kg body weight on favorable 90-day outcome (defined as mRS 0-2), the rate of symptomatic intracranial hemorrhage, and poor 90-day outcome (mRS 4-6).

RESULTS

Among 873 patients treated with IV rt-PA, a total of 105 (12%) subjects had body weight >100 kg. Compared with patients having ≤100 kg body weight, the rate of favorable outcome at 90 days was not significantly different among patients with >100 kg body weight (OR: 0.99; 95% CI: 0.91-1.01; p=0.91) , after adjusting for potential confounders. The ordinal analysis did not show any significant shift in the distribution of 90-day mRS score in patients with >100 kg body weight (OR, 0.93; 95% CI, 0.64-1.37; P = 0.74) CONCLUSIONS: There was no reduction in the rate of favorable outcome in patients with acute ischemic stroke with body weight >100 kg who received <0.9 mg/kg dose of IV rt-PA. Our results support the current recommendations in the ASA/AHA guidelines.

Treatment effect on ordinal functional outcome using piecewise multistate Markov model with unobservable baseline: an application to the modified Rankin scale

In clinical trials, longitudinally assessed ordinal outcomes are commonly dichotomized and only the final measure is used for primary analysis, partly for ease of clinical interpretation. Dichotomization of the ordinal scale and failure to utilize the repeated measures can reduce statistical power. Additionally, in certain emergent settings, the same measure cannot be assessed at baseline prior to treatment. For such a data set, a piecewise-constant multistate Markov model that incorporates a latent model for the unobserved baseline measure is proposed. These models can be useful in analyzing disease history data and are advantageous in clinical applications where a disease process naturally moves through increasing stages of severity. Two examples are provided using acute stroke clinical trials data. Conclusions drawn in this article are consistent with those from the primary analysis for treatment effect in both of the motivating examples. Use of these models allows for a more refined examination of treatment effect and describes the movement between health states from baseline to follow-up visits which may provide more clinical insight into the treatment effect.

Bayesian dose selection design for a binary outcome using restricted response adaptive randomization

Background

In phase II trials, the most efficacious dose is usually not known. Moreover, given limited resources, it is difficult to robustly identify a dose while also testing for a signal of efficacy that would support a phase III trial. Recent designs have sought to be more efficient by exploring multiple doses through the use of adaptive strategies. However, the added flexibility may potentially increase the risk of making incorrect assumptions and reduce the total amount of information available across the dose range as a function of imbalanced sample size.

Methods

To balance these challenges, a novel placebo-controlled design is presented in which a restricted Bayesian response adaptive randomization (RAR) is used to allocate a majority of subjects to the optimal dose of active drug, defined as the dose with the lowest probability of poor outcome. However, the allocation between subjects who receive active drug or placebo is held constant to retain the maximum possible power for a hypothesis test of overall efficacy comparing the optimal dose to placebo. The design properties and optimization of the design are presented in the context of a phase II trial for subarachnoid hemorrhage.

Results

For a fixed total sample size, a trade-off exists between the ability to select the optimal dose and the probability of rejecting the null hypothesis. This relationship is modified by the allocation ratio between active and control subjects, the choice of RAR algorithm, and the number of subjects allocated to an initial fixed allocation period. While a responsive RAR algorithm improves the ability to select the correct dose, there is an increased risk of assigning more subjects to a worse arm as a function of ephemeral trends in the data. A subarachnoid treatment trial is used to illustrate how this design can be customized for specific objectives and available data.

Conclusions

Bayesian adaptive designs are a flexible approach to addressing multiple questions surrounding the optimal dose for treatment efficacy within the context of limited resources. While the design is general enough to apply to many situations, future work is needed to address interim analyses and the incorporation of models for dose response.

Expanding the concept of neuroprotection for acute ischemic stroke: The pivotal roles of reperfusion and the collateral circulation

This review surveys the efforts taken to achieve clinically efficacious protection of the ischemic brain and underscores the necessity of expanding our purview to include the essential role of cerebral perfusion and the collateral circulation. We consider the development of quantitative strategies to measure cerebral perfusion at the regional and local levels and the application of these methods to elucidate flow-related thresholds of ischemic viability and to characterize the ischemic penumbra. We stress that the modern concept of neuroprotection must consider perfusion, the necessary substrate upon which ischemic brain survival depends. We survey the major mechanistic approaches to neuroprotection and review clinical neuroprotection trials, focusing on those phase 3 multicenter clinical trials for acute ischemic stroke that have been completed or terminated. We review the evolution of thrombolytic therapies; consider the lessons learned from the initial, negative multicenter trials of endovascular therapy; and emphasize the highly successful positive trials that have finally established a clinical role for endovascular clot removal. As these studies point to the brain's collateral circulation as key to successful reperfusion, we next review the anatomy and pathophysiology of collateral perfusion as it relates to ischemic infarction, as well as the molecular and genetic influences on collateral development. We discuss the current MR and CT-based diagnostic methods for assessing the collateral circulation and the prognostic significance of collaterals in ischemic stroke, and we consider past and possible future therapeutic directions.

Topographic Assessment of Acute Ischemic Changes for Prognostication of Anterior Circulation Stroke

BACKGROUND

The location of acute ischemic infarct can affect the clinical outcome of stroke patients. We aimed to develop a prognostic tool based on the topographic distribution of early ischemic changes on admission computed tomography (CT) scans.

METHODS

Using the albumin in acute stroke (ALIAS) trials dataset, patients with anterior circulation stroke were included for analysis. A 3-month modified Rankin scale (mRs) score > 2 defined disability/death; and ≤2 defined favorable outcome. A penalized logistic regression determined independent predictors of disability/death among components of admission CT scan Alberta Stroke Program Early CT score (ASPECTS). Follow-up 24-hour CT/MRI scans were reviewed for intracranial hemorrhage (ICH).

RESULTS

A simplified ASPECTS (sASPECTS) was developed including the caudate, lentiform nucleus, insula, and M5 components of ASPECTS-which were independent predictors of disability/death on multivariate analysis. There was no significant difference between ASPECTS and sASPECTS in prediction of disability/death (P = .738). Among patients with sASPECTS ≥ 1, the rate of favorable outcome was higher in those with intravenous (IV) thrombolytic therapy (501/837, 59.9%) versus those without treatment (91/183, 49.7%, P = .013); whereas among patients with sASPECTS of 0, IV thrombolysis was not associated with improved outcome. Also, patients with sASPECTS of 0 were more likely to develop symptomatic ICH (odds ratio = 2.62, 95% confidence interval: 1.49-4.62), compared to those with sASPECTS ≥ 1 (P = .004).

CONCLUSIONS

Topographic assessment of acute ischemic changes using the sASPECTS (including caudate, lentiform nucleus, insula, and M5) can predict disability/death in anterior circulation stroke as accurately as the ASPECTS; and may help predict response to treatment and risk of developing symptomatic ICH.

ALIAS (Albumin in Acute Ischemic Stroke) Trials: Analysis of the Combined Data From Parts 1 and 2

BACKGROUND AND PURPOSE

The ALIAS (Albumin in Acute Ischemic Stroke) part 1 and 2 trials evaluated whether 25% human serum albumin improves clinical outcomes after acute ischemic stroke above and beyond standard of care using similar protocols. The part 1 trial ended prematurely because of safety concerns, and the part 2 trial terminated early because of futility of finding a statistically significant effect of albumin over saline (control) administration. We combine the subject-level data of the part 1 and 2 trials to reevaluate the efficacy and safety outcomes with the larger sample size.

METHODS

The combined data analyses closely follow those conducted in the part 2 trial. The primary outcome is the composite of the modified Rankin Scale and the National Institutes of Health Stroke Scale defined as a composite of modified Rankin Scale score 0 to 1 and National Institutes of Health Stroke Scale score 0 to 1 at 90 days from randomization. The unadjusted analyses use a simple Chi-square test, and those adjusting for baseline covariates use a generalized linear model with log link (to obtain relative risks).

RESULTS

The participant characteristics at baseline were generally similar between the treatment groups and between the trials; however, thrombolysis use was greater in part 2 (84% versus 75%), and the upper age limit imposed in part 2 resulted in a younger sample (mean age in part 1 was 69 versus 64 in part 2). In the combined sample, the proportions of good outcome in the 2 treatment groups were identical (41%). Similar results were observed in all secondary efficacy outcomes. Pulmonary edema was a consistent safety concern, with a 6-fold increase in the albumin arm (13%) compared with saline (2%; relative risk =7.76, 95% confidence interval 3.87-15.57).

CONCLUSIONS

Treatment with intravenous albumin 25% at 2 g/kg was not associated with improved outcome at 90 days and was associated with increased rates of intracerebral hemorrhage and pulmonary edema.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00235495.

An Outcome Model for Intravenous rt-PA in Acute Ischemic Stroke

Most early phase trials in stroke and brain trauma have failed in phase 3, including efforts to improve acute ischemic stroke outcomes beyond that achieved by intravenous recombinant tissue plasminogen activator (t-PA) (IVT). With the exception of more recent stent retriever trials, most subsequent phase 3 trials failed. We previously showed that baseline imbalances, non-linear relationships of these factors to outcome, and unrepresentative control populations invalidate traditional statistical analysis in early trials of heterogeneous diseases such as stroke. We developed an alternative approach using a pooled outcome model derived from control arms of randomized clinical trial (RCTs). This model then permits comparing treatment trials to an expected outcome of a pooled population. Here, we hypothesized we could develop such a model for IVT and tested it against outcomes without IVT. We surveyed literature for all trials involving one arm with IVT reporting baseline National Institute Stroke Scale (NIHSS), age, and outcome. A non-linear fit was performed including multi-dimensional statistical intervals (±95 %) permitting visual comparison of outcomes at their own baselines. We compared models derived from non-IVT control arms. Models from 24 IVT RCTs representing 3195 subjects were successfully generated for functional outcome, modified Rankin Scale (mRS) 0-2 (r(2) = 0. 83, p < 0.001), and mortality (r(2) = 0.54; p = 0.001). We confirmed better outcomes compared to no IVT and mixed use IVT models across the range of baseline factors. It was possible to generate an expected outcome model for IVT from existing literature. We confirmed benefit compared to placebo. This model should be useful to compare to new agents without the need for statistical manipulation.

Albumin Administration in Acute Ischemic Stroke: Safety Analysis of the ALIAS Part 2 Multicenter Trial

BACKGROUND

Albumin treatment of ischemic stroke was associated with cardiopulmonary adverse events in previous studies and a low incidence of intracranial hemorrhage. We sought to describe the neurological and cardiopulmonary adverse events in the ALIAS Part 2 Multicenter Trial.

METHODS

Ischemic stroke patients, aged 18-83 and a baseline NIHSS ≥ 6, were randomized to treatment with ALB or saline control within 5 hours of stroke onset. Neurological adverse events included symptomatic intracranial hemorrhage, hemicraniectomy, neurological deterioration and neurological death. Cardiopulmonary adverse events included pulmonary edema/congestive heart failure, acute coronary syndromes, atrial fibrillation, pneumonia and pulmonary thromboembolism.

RESULTS

Among 830 patients, neurological and cardiopulmonary adverse events were not differentially associated with poor outcome between ALB and saline control subjects. The rate of symptomatic intracranial hemorrhage in the first 24h was low overall (2.9%, 24/830) but more common in the ALB treated subjects (RR = 2.4, CI95 1.01-5.8). The rate of pulmonary edema/CHF in the first 48h was 7.9% (59/830) and was more common among ALB treated subjects (RR = 10.7, CI95 4.3-26.6); this complication was expected and was satisfactorily managed with mandated diuretic administration and intravenous fluid guidelines. Troponin elevations in the first 48h were common, occurring without ECG change or cardiac symptoms in 52 subjects (12.5%).

CONCLUSIONS

ALB therapy was associated with an increase in symptomatic ICH and pulmonary edema/congestive heart failure but this did not affect final outcomes. Troponin elevation occurs routinely in the first 48 hours after acute ischemic stroke.

TRIAL REGISTRATION

ClincalTrials.gov NCT00235495.

A Model for Predicting Development of Overt Hepatic Encephalopathy in Patients With Cirrhosis

BACKGROUND & AIMS

Overt hepatic encephalopathy (HE) affects patients' quantity and quality of life and places a burden on families. There is evidence that overt HE might be prevented pharmacologically, but prophylaxis would be justified and cost effective only for patients at risk. We aimed to identify patients with cirrhosis at risk for overt HE.

METHODS

We collected data from October 2009 through December 2012 for 216 consecutive patients with cirrhosis (based on liver biopsy, 96 patients with minimal HE), admitted to the Gastroenterology Unit at the University of Rome. Patients were followed up and evaluated for an average of 14.7 ± 11.6 months; development of overt HE was recorded. We analyzed end-stage liver disease scores, shunt placement, previous overt or minimal HE, psychometric hepatic encephalopathy score (PHES), and levels of albumin, bilirubin, creatinine, and sodium to develop a prediction model. We validated the model in 112 patients with cirrhosis seen at the University of Padua and followed up for 12 ± 9.5 months.

RESULTS

During the follow-up period, 68 patients (32%) developed at least 1 episode of overt HE. Based on multivariate analysis, the development of overt HE was associated with previous HE, minimal HE (based on PHES), and level of albumin less than 3.5 g/dL (area under curve [AUC], 0.74). A model that excluded minimal HE but included albumin level and previous HE also identified patients who would develop overt HE (AUC, 0.71); this difference in AUC values was not statistically significant (P = .104). Both models were validated in the independent group of patients (3 variables: AUC, 0.74; 95% confidence interval, 0.66-0.83; and 2 variables: AUC, 0.71; 95% confidence interval, 0.63-0.78).

CONCLUSIONS

We developed and validated a model to identify patients with cirrhosis at risk for overt HE based on previous HE, albumin levels, and PHES. If PHES was not available, previous HE and albumin levels still can identify patients at risk. Psychometric evaluation is essential for patients with no history of HE. These findings should aid in planning studies of pharmacologic prevention of overt HE.

Impaired leptomeningeal collateral flow contributes to the poor outcome following experimental stroke in the Type 2 diabetic mice

Collateral status is an independent predictor of stroke outcome. However, the spatiotemporal manner in which collateral flow maintains cerebral perfusion during cerebral ischemia is poorly understood. Diabetes exacerbates ischemic brain damage, although the impact of diabetes on collateral dynamics remains to be established. Using Doppler optical coherent tomography, a robust recruitment of leptomeningeal collateral flow was detected immediately after middle cerebral artery (MCA) occlusion in C57BL/6 mice, and it continued to grow over the course of 1 week. In contrast, an impairment of collateral recruitment was evident in the Type 2 diabetic db/db mice, which coincided with a worse stroke outcome compared with their normoglycemic counterpart db/+, despite their equally well-collateralized leptomeningeal anastomoses. Similar to the wild-type mice, both db/+ and db/db mice underwent collateral growth 7 d after MCA stroke, although db/db mice still exhibited significantly reduced retrograde flow into the MCA territory chronically. Acutely induced hyperglycemia in the db/+ mice did not impair collateral flow after stroke, suggesting that the state of hyperglycemia alone was not sufficient to impact collateral flow. Human albumin was efficacious in improving collateral flow and outcome after stroke in the db/db mice, enabling perfusion to proximal MCA territory that was usually not reached by retrograde flow from anterior cerebral artery without treatment. Our results suggest that the impaired collateral status contributes to the exacerbated ischemic injury in mice with Type 2 diabetes, and modulation of collateral flow has beneficial effects on stroke outcome among these subjects.

Effect of human albumin on TCD vasospasm, DCI, and cerebral infarction in subarachnoid hemorrhage: the ALISAH study

BACKGROUND AND PURPOSE

The neuroprotective effects of human albumin have been studied in animal models of stroke and in humans with various intracranial disorders. We investigated the effect of 25 % human albumin (ALB) on mean cerebral blood flow velocities (MCBFV), delayed cerebral ischemia (DCI), and cerebral infarction.

METHODS

We studied patients from the Albumin in Subarachnoid Hemorrhage (ALISAH) pilot clinical trial. We collected data on MCBFV as measured by transcranial Doppler ultrasound (TCD), incidence of DCI, and cerebral infarctions on head computed tomography (CT) scan at 90 days.

RESULTS

TCD showed vasospasm in 75 % (n = 15), 55 % (n = 11), and 29 % (n = 2) of subjects in dosage tiers 1, 2, and 3, respectively. DCI was present in 20 % (n = 4), 15 % (n = 3), and 14 % (n = 1) of subjects in dosage tiers 1, 2, and 3, respectively. Cerebral infarctions were seen in 45 % (5 of 9), 27 % (3 of 18), and 25 % (1 of 4) of subjects who had follow-up head CT scans in dosage tiers 1, 2, and 3, respectively.

CONCLUSIONS

Higher dosages of ALB were associated with a lower incidence of TCD vasospasm, DCI, and cerebral infarction at 90 days in a dose-dependent manner.

Endovascular treatment for Small Core and Anterior circulation Proximal occlusion with Emphasis on minimizing CT to recanalization times (ESCAPE) trial: methodology

ESCAPE is a prospective, multicenter, randomized clinical trial that will enroll subjects with the following main inclusion criteria: less than 12 h from symptom onset, age > 18, baseline NIHSS >5, ASPECTS score of >5 and CTA evidence of carotid T/L or M1 segment MCA occlusion, and at least moderate collaterals by CTA. The trial will determine if endovascular treatment will result in higher rates of favorable outcome compared with standard medical therapy alone. Patient populations that are eligible include those receiving IV tPA, tPA ineligible and unwitnessed onset or wake up strokes with 12 h of last seen normal. The primary end-point, based on intention-to-treat criteria is the distribution of modified Rankin Scale scores at 90 days assessed using a proportional odds model. The projected maximum sample size is 500 subjects. Randomization is stratified under a minimization process using age, gender, baseline NIHSS, baseline ASPECTS (8-10 vs. 6-7), IV tPA treatment and occlusion location (ICA vs. MCA) as covariates. The study will have one formal interim analysis after 300 subjects have been accrued. Secondary end-points at 90 days include the following: mRS 0-1; mRS 0-2; Barthel 95-100, EuroQOL and a cognitive battery. Safety outcomes are symptomatic ICH, major bleeding, contrast nephropathy, total radiation dose, malignant MCA infarction, hemicraniectomy and mortality at 90 days.

Human albumin administration in subarachnoid hemorrhage: results of an international survey

BACKGROUND

Subarachnoid hemorrhage (SAH) is a devastating disease. Nimodipine is the only medical treatment shown to improve outcome of SAH patients. Human albumin (ALB) may exert neuroprotection in SAH. However, current usage of ALB in SAH is not known. We conducted an international survey of clinicians involved in the care of SAH patients to determine current practice of ALB administration in SAH.

METHODS

We constructed a 27-question survey. Our sampling frame consisted of neurointensivists, general intensivists, neurocritical care nurses, critical care pharmacists, and neurosurgeons. The survey was available from 11/15/2012 to 12/15/2012. We performed mostly descriptive statistical analysis.

RESULTS

We obtained 362 responses from a diverse range of world regions. Most respondents were intensivist physicians (88 %), who worked in academic institutions (73.5 %) with a bed capacity >500 (64.1 %) and an established institutional management protocol for SAH patients (70.2 %). Most respondents (83.5 %) indicated that their institutions do not incorporate ALB in their protocol, but half of them (45.9 %) indicated using ALB outside it. ALB administration is influenced by several factors: geographic variation (more common among US respondents); institutions with a dedicated neuroICU; and availability of SAH management protocol. Most respondents (75 %) indicated that a clinical trial to test the efficacy of ALB in SAH is needed.

CONCLUSIONS

In this survey we found that ALB administration in SAH patients is common and influenced by several factors. Majority of respondents support a randomized clinical trial to determine the safety and efficacy of ALB administration in SAH patients.

Flow Augmentation in Acute Ischemic Stroke

There is an urgent need for additional therapeutic options for acute ischemic stroke considering the major pitfalls of the options available. Herein, we briefly review the role of cerebral blood flow, collaterals, vasoreactivity, and reperfusion injury in acute ischemic stroke. Then, we reviewed pharmacological and interventional measures such as volume expansion and induced hypertension, intra-aortic balloon counterpulsation, partial aortic occlusion, extracranial-intracranial carotid bypass surgery, sphenopalatine ganglion stimulation, and transcranial laser therapy with regard to their effects on flow augmentation and neuroprotection.

Haemodilution for acute ischaemic stroke

BACKGROUND

Ischaemic stroke interrupts the flow of blood to part of the brain. Haemodilution is thought to improve the flow of blood to the affected areas of the brain and thus reduce infarct size.

OBJECTIVES

To assess the effects of haemodilution in acute ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (February 2014), the Cochrane Central Register of Controlled Trials (Issue 1, 2014), MEDLINE (January 2008 to October 2013) and EMBASE (January 2008 to October 2013). We also searched trials registers, scanned reference lists and contacted authors. For the previous version of the review, the authors contacted manufacturers and investigators in the field.

SELECTION CRITERIA

Randomised trials of haemodilution treatment in people with acute ischaemic stroke. We included only trials in which treatment was started within 72 hours of stroke onset.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial quality and one review author extracted the data.

MAIN RESULTS

We included 21 trials involving 4174 participants. Nine trials used a combination of venesection and plasma volume expander. Twelve trials used plasma volume expander alone. The plasma volume expander was plasma alone in one trial, dextran 40 in 12 trials, hydroxyethyl starch (HES) in five trials and albumin in three trials. Two trials tested haemodilution in combination with another therapy. Evaluation was blinded in 14 trials. Five trials probably included some participants with intracerebral haemorrhage. Haemodilution did not significantly reduce deaths within the first four weeks (risk ratio (RR) 1.10; 95% confidence interval (CI) 0.90 to 1.34). Similarly, haemodilution did not influence deaths within three to six months (RR 1.05; 95% CI 0.93 to 1.20), or death and dependency or institutionalisation (RR 0.96; 95% CI 0.85 to 1.07). The results were similar in confounded and unconfounded trials, and in trials of isovolaemic and hypervolaemic haemodilution. No statistically significant benefits were documented for any particular type of haemodiluting agents, but the statistical power to detect effects of HES was weak. Six trials reported venous thromboembolic events. There was a tendency towards reduction in deep venous thrombosis or pulmonary embolism or both at three to six months' follow-up (RR 0.68; 95% CI 0.37 to 1.24). There was no statistically significant increased risk of serious cardiac events among haemodiluted participants.

AUTHORS' CONCLUSIONS

The overall results of this review showed no clear evidence of benefit of haemodilution therapy for acute ischaemic stroke.These results are compatible with no persuasive beneficial evidence of haemodilution therapy for acute ischaemic stroke. This therapy has not been proven to improve survival or functional outcome.

Discovery of prognostic biomarker candidates of lacunar infarction by quantitative proteomics of microvesicles enriched plasma

Background

Lacunar infarction (LACI) is a subtype of acute ischemic stroke affecting around 25% of all ischemic stroke cases. Despite having an excellent recovery during acute phase, certain LACI patients have poor mid- to long-term prognosis due to the recurrence of vascular events or a decline in cognitive functions. Hence, blood-based biomarkers could be complementary prognostic and research tools.

Methods and Finding

Plasma was collected from forty five patients following a non-disabling LACI along with seventeen matched control subjects. The LACI patients were monitored prospectively for up to five years for the occurrence of adverse outcomes and grouped accordingly (i.e., LACI-no adverse outcome, LACI-recurrent vascular event, and LACI-cognitive decline without any recurrence of vascular events). Microvesicles-enriched fractions isolated from the pooled plasma of four groups were profiled by an iTRAQ-guided discovery approach to quantify the differential proteome. The data have been deposited to the ProteomeXchange with identifier PXD000748. Bioinformatics analysis and data mining revealed up-regulation of brain-specific proteins including myelin basic protein, proteins of coagulation cascade (e.g., fibrinogen alpha chain, fibrinogen beta chain) and focal adhesion (e.g., integrin alpha-IIb, talin-1, and filamin-A) while albumin was down-regulated in both groups of patients with adverse outcome.

Conclusion

This data set may offer important insight into the mechanisms of poor prognosis and provide candidate prognostic biomarkers for validation on larger cohort of individual LACI patients.

Ginsenoside Rd for acute ischemic stroke: translating from bench to bedside

Numerous studies have identified pathophysiological mechanisms of acute ischemic stroke and have provided proof-of-principle evidence that strategies designed to impede the ischemic cascade, namely neuroprotection, can protect the ischemic brain. However, the translation of these therapeutic agents to the clinic has not been successful. Ginsenoside Rd, a dammarane-type steroid glycoside extracted from ginseng plants, has exhibited an encouraging neuroprotective efficacy in both laboratory and clinical studies. This article attempts to provide a synopsis of the physiochemical profile, pharmacokinetics, pharmacodynamics, clinical efficacy, safety and putative therapeutic mechanisms of Rd. Finally, the authors discuss the validity of Rd as a neuroprotective agent for acute ischemic stroke.

Effects of intravenous albumin in patients with cirrhosis and episodic hepatic encephalopathy: a randomized double-blind study

BACKGROUND & AIMS

Episodic hepatic encephalopathy is frequently precipitated by factors that induce circulatory dysfunction, cause oxidative stress-mediated damage or enhance astrocyte swelling. The administration of albumin could modify these factors and improve the outcome of hepatic encephalopathy. The aim of this study is to assess the efficacy of albumin in a multicenter, prospective, double-blind, controlled trial (ClinicalTrials.gov number, NCT00886925).

METHODS

Cirrhotic patients with an acute episode of hepatic encephalopathy (grade II-IV) were randomized to receive albumin (1.5g/kg on day 1 and 1.0g/kg on day 3) or isotonic saline, in addition to the usual treatment (laxatives, rifaximin 1200mg per day). The primary end point was the proportion of patients in which encephalopathy was resolved on day 4. The secondary end points included survival, length of hospital stay, and biochemical parameters.

RESULTS

Fifty-six patients were randomly assigned to albumin (n=26) or saline (n=30) stratified by the severity of HE. Both groups were comparable regarding to demographic data, liver function, and precipitating factors. The percentage of patients without hepatic encephalopathy at day 4 did not differ between both groups (albumin: 57.7% vs. saline: 53.3%; p>0.05). However, significant differences in survival were found at day 90 (albumin: 69.2% vs. saline: 40.0%; p=0.02).

CONCLUSIONS

Albumin does not improve the resolution of hepatic encephalopathy during hospitalization. However, differences in survival after hospitalization suggest that the development of encephalopathy may identify a subgroup of patients with advanced cirrhosis that may benefit from the administration of albumin.

High-dose albumin treatment for acute ischaemic stroke (ALIAS) Part 2: a randomised, double-blind, phase 3, placebo-controlled trial

BACKGROUND

In animal models of ischaemic stroke, 25% albumin reduced brain infarction and improved neurobehavioural outcome. In a pilot clinical trial, albumin doses as high as 2 g/kg were safely tolerated. We aimed to assess whether albumin given within 5 h of the onset of acute ischaemic stroke increased the proportion of patients with a favourable outcome.

METHODS

We did a randomised, double-blind, parallel-group, phase 3, placebo-controlled trial between Feb 27, 2009, and Sept 10, 2012, at 69 sites in the USA, 13 sites in Canada, two sites in Finland, and five sites in Israel. Patients aged 18-83 years with ischaemic (ie, non-haemorrhagic) stroke with a baseline National Institutes of Health stroke scale (NIHSS) score of 6 or more who could be treated within 5 h of onset were randomly assigned (1:1), via a central web-based randomisation process with a biased coin minimisation approach, to receive 25% albumin (2 g [8 mL] per kg; maximum dose 750 mL) or the equivalent volume of isotonic saline. All study personnel and participants were masked to the identity of the study drug. The primary endpoint was favourable outcome, defined as either a modified Rankin scale score of 0 or 1, or an NIHSS score of 0 or 1, or both, at 90 days. Analysis was by intention to treat. Thrombolytic therapies were permitted. This trial is registered with ClinicalTrials.gov, number NCT00235495.

FINDINGS

422 participants were randomly assigned to receive albumin and 419 to receive saline. On Sept 12, 2012, the trial was stopped early for futility (n=841). The primary outcome did not differ between patients in the albumin group and those in the saline group (186 [44%] vs 185 [44%]; risk ratio 0·96, 95% CI 0·84-1·10, adjusted for baseline NIHSS score and thrombolysis stratum). Mild-to-moderate pulmonary oedema was more common in patients given albumin than in those given saline (54 [13%] of 412 vs 5 [1%] of 412 patients); symptomatic intracranial haemorrhage within 24 h was also more common in patients in the albumin group than in the placebo group (17 [4%] of 415 vs 7 [2%] of 414 patients). Although the rate of favourable outcome in patients given albumin remained consistent at 44-45% over the course of the trial, the cumulative rate of favourable outcome in patients given saline rose steadily from 31% to 44%.

INTERPRETATION

Our findings show no clinical benefit of 25% albumin in patients with ischaemic stroke; however, they should not discourage further efforts to identify effective strategies to protect the ischaemic brain, especially because of preclinical literature showing convincing proof-of-principle for the possibility of this outcome.

FUNDING

National Institute of Neurological Disorders and Stroke, US National Institutes of Health; and Baxter Healthcare Corporation.

Bayesian adaptive trials offer advantages in comparative effectiveness trials: an example in status epilepticus

OBJECTIVE

We present a novel Bayesian adaptive comparative effectiveness trial comparing three treatments for status epilepticus that uses adaptive randomization with potential early stopping.

STUDY DESIGN AND SETTING

The trial will enroll 720 unique patients in emergency departments and uses a Bayesian adaptive design.

RESULTS

The trial design is compared to a trial without adaptive randomization and produces an efficient trial in which a higher proportion of patients are likely to be randomized to the most effective treatment arm while generally using fewer total patients and offers higher power than an analogous trial with fixed randomization when identifying a superior treatment.

CONCLUSION

When one treatment is superior to the other two, the trial design provides better patient care, higher power, and a lower expected sample size.

Molecular Dissection of Cyclosporin A's Neuroprotective Effect Reveals Potential Therapeutics for Ischemic Brain Injury

After the onset of brain ischemia, a series of events leads ultimately to the death of neurons. Many molecules can be pharmacologically targeted to protect neurons during these events, which include glutamate release, glutamate receptor activation, excitotoxicity, Ca²⁺ influx into cells, mitochondrial dysfunction, activation of intracellular enzymes, free radical production, nitric oxide production, and inflammation. There have been a number of attempts to develop neuroprotectants for brain ischemia, but many of these attempts have failed. It was reported that cyclosporin A (CsA) dramatically ameliorates neuronal cell damage during ischemia. Some researchers consider ischemic cell death as a unique process that is distinct from both apoptosis and necrosis, and suggested that mitochondrial dysfunction and Δψ collapse are key steps for ischemic cell death. It was also suggested that CsA has a unique neuroprotective effect that is related to mitochondrial dysfunction. Here, I will exhibit examples of neuroprotectants that are now being developed or in clinical trials, and will discuss previous researches about the mechanism underlying the unique CsA action. I will then introduce the results of our cDNA subtraction experiment with or without CsA administration in the rat brain, along with our hypothesis about the mechanism underlying CsA’s effect on transcriptional regulation.

Serum albumin levels in ischemic stroke and its subtypes: correlation with clinical outcome

OBJECTIVE

Previous studies have associated low serum albumin levels with poor outcome in ischemic stroke. Animal studies also demonstrated neuroprotective effects of serum albumin in focal ischemia. However, there are very limited studies on the association of serum albumin levels with stroke outcome in ischemic stroke divided into subtypes. The present study was carried out to investigate the association of serum albumin levels with outcome in ischemic stroke and its subtypes.

METHODS

The study involved 560 patients. Serum albumin levels were estimated and follow-up interviews were conducted at 3 mo postevent to determine stroke outcome. The association between serum albumin levels and stroke outcome was evaluated by multiple logistic regression analysis after adjustment for potential confounders.

RESULTS

Low levels of albumin associated significantly with poor outcome (score of >3 on the modified Rankin Scale). The adjusted odds ratio was 1.972 (95% confidence interval, 1.103-4.001; P < 0.001). The recurrence of stroke and death rate also was high in patients with low levels of albumin compared with patients with elevated levels of albumin. The reduced level of serum albumin associated significantly with poor outcome in all the stroke subtypes classified according to TOAST (Trial of ORG 10172 in Acute Stroke Treatment).

CONCLUSIONS

Relatively high serum albumin levels in acute stroke decrease poor outcome.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.

Albumin therapy enhances collateral perfusion after laser-induced middle cerebral artery branch occlusion: a laser speckle contrast flow study

Laser speckle contrast (LSC) was used to compare the extent of cortical ischemia in two inbred mouse strains that differed in their degree of collateral circulation, after laser occlusion of the distal middle cerebral artery, and after treatment with 25% albumin (ALB) or saline (control). Sequential LSC images acquired over ∼90 minutes were coaligned, converted to relative flow, and normalized to baseline. After 3-day survival, infarction was quantified by triphenyl tetrazolium chloride or magnetic resonance imaging. In the sparsely collateralized BALB/c strain, mean flow fell to 13% to 14% and 33% to 34% of baseline in central (core) and peripheral (penumbral) regions of interest, and ALB treatment at 30 minutes enhanced perfusion in both regions by ∼2-fold relative to saline, restoring flow to the benign-oligemic range centrally, and to the hyperemic range peripherally. The ALB-induced increment in parenchymal perfusion was disproportionate to the subtle flow increase in the occluded artery itself, suggesting that ALB improved collateral circulation. Cortical infarction in BALB/c mice was reduced 45% by ALB treatment. In contrast to BALB/c mice, the better-collateralized CD-1 strain developed milder ischemia, had smaller infarcts, and showed no differential benefit of ALB. We conclude that where native collateralization is insufficient (BALB/c strain), ALB treatment exerts a significant therapeutic effect after ischemia by augmenting collateral perfusion.

Neuroprotection for stroke: current status and future perspectives

Neuroprotection aims to prevent salvageable neurons from dying. Despite showing efficacy in experimental stroke studies, the concept of neuroprotection has failed in clinical trials. Reasons for the translational difficulties include a lack of methodological agreement between preclinical and clinical studies and the heterogeneity of stroke in humans compared to homogeneous strokes in animal models. Even when the international recommendations for preclinical stroke research, the Stroke Academic Industry Roundtable (STAIR) criteria, were followed, we have still seen limited success in the clinic, examples being NXY-059 and haematopoietic growth factors which fulfilled nearly all the STAIR criteria. However, there are a number of neuroprotective treatments under investigation in clinical trials such as hypothermia and ebselen. Moreover, promising neuroprotective treatments based on a deeper understanding of the complex pathophysiology of ischemic stroke such as inhibitors of NADPH oxidases and PSD-95 are currently evaluated in preclinical studies. Further concepts to improve translation include the investigation of neuroprotectants in multicenter preclinical Phase III-type studies, improved animal models, and close alignment between clinical trial and preclinical methodologies. Future successful translation will require both new concepts for preclinical testing and innovative approaches based on mechanistic insights into the ischemic cascade.

Docosahexaenoic acid complexed to human albumin in experimental stroke: neuroprotective efficacy with a wide therapeutic window

BACKGROUND

Docosahexaenoic acid (DHA) complexed to human serum albumin (Alb) is neuroprotective after experimental stroke. Here we tested using lower concentrations of albumin as part of the complex to achieve neuroprotection. We found that lower Alb concentrations extend the therapeutic window of protection beyond 5 h after stroke onset.

METHODS

Sprague-Dawley rats were received 2 h middle cerebral artery occlusion (MCAo). The behavior was evaluated on day 1, 2, 3 and 7 after MCAo. In the dose-response study, animals were given either DHA (5mg/kg), Alb (0.63g/kg), DHA-Alb (5mg/kg + 0.32, 0.63 or 1.25 g/kg) or saline, i.v. 3 h after onset of stroke (n=6-8 per group). In the therapeutic window study, DHA-Alb (5mg/kg + 1.25g/kg) was administered i.v. at either 3, 4, 5, 6 or 7 h after onset of stroke (n=7-9 per group). Alb (1.25g/kg) was given at 3 h or 5 h and saline at 3h after onset of reperfusion. Seven days after MCAo, infarct volumes and number of GFAP, ED-1, NeuN, SMI-71 positive cells and vessels were counted.

RESULTS

Moderate DHA-Alb doses (0.63 and 1.25 g/kg) improved neurological scores compared to albumin-treated rats on days 1, 2, 3 and 7. All DHA-Alb doses (0.32, 0.63 and 1.25 g/kg) markedly reduced cortical (by 65-70%), striatal (by 52-63%) and total infarct volumes (by 60-64%) compared to native Alb group. In the therapeutic window study DHA-Alb led to improved neurological score and significant reductions of infarct volumes (especially in the cortical or penumbral region), even when treatment was initiated as late as 7 hours after onset of MCAo.

CONCLUSIONS

The DHA-Alb complex affords high-grade neurobehavioral neuroprotection in focal cerebral ischemia, equaling or exceeding that afforded by native Alb or DHA, at considerably moderate doses. It has a broad therapeutic window extending to 7 h after stroke onset. Taken together, these finding support the potential clinical feasibility of administering DHA-Alb therapy to patients with acute ischemic stroke.

Albumin induces upregulation of matrix metalloproteinase-9 in astrocytes via MAPK and reactive oxygen species-dependent pathways

BACKGROUND

Astrocytes are an integral component of the blood-brain barrier (BBB) which may be compromised by ischemic or traumatic brain injury. In response to trauma, astrocytes increase expression of the endopeptidase matrix metalloproteinase (MMP)-9. Compromise of the BBB leads to the infiltration of fluid and blood-derived proteins including albumin into the brain parenchyma. Albumin has been previously shown to activate astrocytes and induce the production of inflammatory mediators. The effect of albumin on MMP-9 activation in astrocytes is not known. We investigated the molecular mechanisms underlying the production of MMP-9 by albumin in astrocytes.

METHODS

Primary enriched astrocyte cultures were used to investigate the effects of exposure to albumin on the release of MMP-9. MMP-9 expression was analyzed by zymography. The involvement of mitogen-activated protein kinase (MAPK), reactive oxygen species (ROS) and the TGF-β receptor-dependent pathways were investigated using pharmacological inhibitors. The production of ROS was observed by dichlorodihydrofluorescein diacetate fluorescence. The level of the MMP-9 inhibitor tissue inhibitor of metalloproteinase (TIMP)-1 produced by astrocytes was measured by ELISA.

RESULTS

We found that albumin induces a time-dependent release of MMP-9 via the activation of p38 MAPK and extracellular signal regulated kinase, but not Jun kinase. Albumin-induced MMP-9 production also involves ROS production upstream of the MAPK pathways. However, albumin-induced increase in MMP-9 is independent of the TGF-β receptor, previously described as a receptor for albumin. Albumin also induces an increase in TIMP-1 via an undetermined mechanism.

CONCLUSIONS

These results link albumin (acting through ROS and the p38 MAPK) to the activation of MMP-9 in astrocytes. Numerous studies identify a role for MMP-9 in the mechanisms of compromise of the BBB, epileptogenesis, or synaptic remodeling after ischemia or traumatic brain injury. The increase in MMP-9 produced by albumin further implicates both astrocytes and albumin in the acute and long-term complications of acute CNS insults, including cerebral edema and epilepsy.

The Albumin in Subarachnoid Hemorrhage (ALISAH) multicenter pilot clinical trial: safety and neurologic outcomes

BACKGROUND AND PURPOSE

Human albumin has been shown to exert neuroprotective effects in animal models of cerebral ischemia and humans with various intracranial pathologies. We investigated the safety and tolerability of 25% human albumin in patients with subarachnoid hemorrhage.

METHODS

The Albumin in Subarachnoid Hemorrhage (ALISAH) Pilot Clinical Trial was an open-label, dose-escalation study. We intended to study 4 different dosages of albumin of increasing magnitude (0.625 g/kg: Tier 1; 1.25 g/kg: Tier 2; 1.875 g/kg: Tier 3; and 2.5 g/kg: Tier 4). Each dosage was to be given to 20 adult patients. Treatment was administered daily for 7 days. We investigated the maximum tolerated dose of albumin based on the rate of severe-to-life-threatening heart failure and anaphylactic reaction and functional outcome at 3 months.

RESULTS

We treated 47 adult subjects: 20 in Tier 1; 20 in Tier 2; and 7 in Tier 3. We found that doses ranging up to 1.25 g/kg/day×7 days were tolerated by patients without major dose-limiting complications. We also found that outcomes trended toward better responses in those subjects enrolled in Tier 2 compared with Tier 1 (OR, 3.0513; CI, 0.6586-14.1367) and with the International Intraoperative Hypothermia for Aneurysm Surgery Trial cohort (OR, 3.1462; CI, 0.9158-10.8089).

CONCLUSIONS

Albumin in doses ranging up to 1.25 g/kg/day×7 days was tolerated by patients with subarachnoid hemorrhage without major complications and may be neuroprotective. Based on these results, planning of the ALISAH II, a Phase III, randomized, placebo-controlled trial to test the efficacy of albumin, is underway.

CLINICAL TRIAL REGISTRATION

URL: http://clinicaltrials.gov. Unique identifier: NCT00283400.

A simple, assumption-free, and clinically interpretable approach for analysis of modified Rankin outcomes

BACKGROUND AND PURPOSE

There is debate regarding the approach for analysis of modified Rankin scale scores, the most common functional outcome scale used in acute stroke trials.

METHODS

We propose to use tests to assess treatment differences addressing the metric, "if a patient is chosen at random from each treatment group and if they have different outcomes, what is the chance the patient who received the investigational treatment will have a better outcome than will the patient receiving the standard treatment?" This approach has an associated statement of treatment efficacy easily understood by patients and clinicians, and leads to statistical testing of treatment differences by tests closely related to the Mann-Whitney U test (Wilcoxon Rank-Sum test), which can be tested precisely by permutation tests (randomization tests).

RESULTS

We show that a permutation test is as powerful as are other approaches assessing ordinal outcomes of the modified Rankin scores, and we provide data from several examples contrasting alternative approaches.

DISCUSSION

Whereas many approaches to analysis of modified Rankin scores outcomes have generally similar statistical performance, this proposed approach: captures information from the ordinal scale, provides a powerful clinical interpretation understood by both patients and clinicians, has power at least equivalent to other ordinal approaches, avoids assumptions in the parameterization, and provides an interpretable parameter based on the same foundation as the calculation of the probability value.

Antioxidant strategies in neurocritical care

An increase in oxidative stress and overproduction of oxidizing reactive species plays an important role in the pathophysiology of several conditions encountered in the neurocritical care setting including: ischemic and hemorrhagic strokes, traumatic brain injury, acute respiratory distress syndrome, sepsis, and organ failure. The presence of oxidative stress in these conditions is supported by a large body of pre-clinical and clinical studies, and provides a rationale to support a potential therapeutic role for antioxidants. The purpose of this article is to briefly review the basic mechanisms and molecular biology of oxidative stress, summarize its role in critically ill neurological patients, and review available data regarding the potential role of antioxidant strategies in neurocritical care and future directions.

Serum albumin as a determinant of cortisol release in patients with acute ischemic stroke

OBJECTIVE

Animal studies demonstrated that protein malnutrition increases pituitary-adrenorcortical activity and leads to excessive cortisol release. The aim of our study was to determine the association between serum albumin and cortisol level in patients with acute ischemic stroke.

METHODS

Fifty-nine patients with first-ever ischemic stroke were included. Serum albumin level was measured within 36 h after stroke symptoms onset. Serum cortisol was measured between 36 and 72 h after stroke onset at 6 a.m., 10 a.m., 6 p.m. and 10 p.m.

RESULTS

The patients in upper tertile of serum albumin had significantly lower cortisol level measured at 6 a.m. (median with interquartiles: 549.0 [430.4-667.7] nmol/L vs 590.4 [482.8-918.7] nmol/L, P=0.047) and 10 a.m. (402.8 [344.9-510.4] nmol/L vs 634.6 [482.8-827.7] nmol/L, P<0.01) than patients in lower and middle tertiles. On logistic regression analysis adjusted for age and stroke severity, patients in lower and middle tertile of serum albumin had about 7-times higher risk of hypercortisolemia than patients in upper tertile (P<0.01).

CONCLUSIONS

Low serum albumin level in patients with ischemic stroke is associated with higher serum cortisol level and predisposes to hypercortisolemia.