A three-item scale for the early prediction of stroke recovery

Risk of recurrence following acute cardioembolic stroke according to lesion size and NIHSS on admission

INTRODUCTION

This study evaluated the risk of stroke recurrence and bleeding in patients with cardioembolic ischemic stroke, according to lesion size and the NIHSS score on admission.

METHODS

Stroke severity was categorized as minor, NIHSS 0-4; moderate, 5-15; severe, >15, while infarct size was categorized as small, medium, or large. The primary outcome was the composite at 90 days of either ischemic (stroke or systemic embolism) or hemorrhagic events (symptomatic intracranial or severe extracranial bleeding).

RESULTS

The cohort for this analysis comprised 2824 patients. At 90 days, 230 outcome events (8.1 %) were recorded. Regarding NIHSS, with the NIHSS 0-4 group as the reference group, on multivariable analysis, NIHSS 5-15 and NIHSS >15 were significantly associated with combined and hemorrhagic outcomes. NIHSS >15 group resulted also significantly associated with ischemic outcome. Concerning lesion size, with the small lesion group as the reference group, on multivariable analysis, medium and large lesions were significantly associated with all outcomes. The ROC graphs suggest that lesion size better-predicted outcome events, compared to NIHSS even on the DeLong test the differences were not statistically significant. In fact, regarding combined outcome, the AUC for lesion size resulted being 0.618 compared to 0.599 for NIHSS. Furthermore, regarding hemorrhagic outcome, the AUC for lesion size was recorded to be 0.649, compared to 0.601. Finally, for ischemic outcome, the AUCs resulted being 0.575 and 0.577, for lesion size and NIHSS, respectively.

CONCLUSION

Lesion size, compared to NIHSS, slightly better-predicted study outcome events in patients with cardioembolic ischemic stroke.

Neuroprotective Effects of Metformin in Stroke Patients: A Systematic Review and Meta-analysis of Cohort Studies

OBJECTIVES

People with diabetes are 1.5 times more likely to experience stroke than those without diabetes, underlining the urgent need to address this issue. Metformin is often the initial medication chosen to manage diabetes mellitus (DM). The purpose of our systematic review and meta-analysis is to explore the potential neuroprotective effects of metformin in individuals who have received it prior to stroke.

METHOD

Our study encompassed cohort studies that drew a comparison between the severity and diverse outcomes of stroke among individuals with DM who were administered metformin prior to the stroke event and those with DM who did not receive the treatment.

RESULTS

Ten studies met the eligibility criteria. Prestroke metformin use was associated with a significantly lower National Institutes of Health Stroke Scale score (mean difference = -1.29, 95% confidence interval: -2.11 to -0.47) in ischemic stroke. Metformin pretreatment in ischemic stroke was associated with increased odds of favorable outcome (mRS < 2) at 90 days (odds ratio [OR] = 1.45, 95% confidence interval [CI]: 1.06 to 1.99), but it was not significant at discharge. Metformin was found to be associated with reduced mortality (OR = 0.52, 95% CI: 0.42 to 0.64) in ischemic stroke. In hemorrhagic stroke, the results showed a significantly lower intracranial hemorrhage volume in prestroke metformin use (mean difference = -4.77, 95% CI: -6.56 to -2.98).

CONCLUSIONS

We found that prestroke metformin use in diabetic patients yielded neuroprotective effects. In ischemic strokes, metformin reduces stroke severity and 90-day mortality; it also improves 90-day functional outcomes. In hemorrhagic strokes, prestroke metformin use can also cause less intracranial hemorrhage volume. Further clinical trials are needed to confirm its efficacy and verify its benefits in stroke management.

David G. Sherman Lecture: Improving Stroke Diagnosis and Treatment-A Journey Toward the End of Time

In the 2024 David G. Sherman Lecture, Steven J. Warach, illustrating with examples from his research, walks through the history of magnetic resonance imaging in acute stroke from the 1990s and early 2000s with the introduction, validation, and application of diffusion-weighted imaging, penumbral imaging (the diffusion-perfusion mismatch), and other imaging markers of the acute stroke pathology into routine clinical practice and stroke trials. The adaptation of diffusion-weighted imaging for clinical scanners in the acute hospital setting began a revolution in ischemic stroke diagnosis as the presence, location, and size of ischemic lesions could now be visualized at the earliest times after stroke onset when computed tomography and conventional magnetic resonance imaging still appeared normal. In combination with perfusion magnetic resonance imaging, diffusion-weighted imaging made imaging of the ischemic penumbra a practical reality for routine clinical use and feasible for integration as a selection tool into clinical trials. It was apparent from the initial use of diffusion-perfusion imaging in acute stroke that many patients had persistence of penumbra as late as 24 hours after stroke onset although the probability of penumbra decreased over time. The therapeutic time window for ischemic stroke selected by clinical and temporal criteria reflected the decreased proportion of patients with the therapeutic target over time rather than the absence of the penumbral target in all patients at later times. This work provided the empirical and conceptual framework for the shift toward selection and evaluation of patients for acute stroke therapies based on direct observation of the target pathology and away from the exclusive dependence on clinical and temporal surrogates to infer the presence of stroke therapeutic targets, a shift that has expanded the indications for acute reperfusion therapies over the last 10 years.

Bioinformatic Exploration of Circulating microRNAs Related to Functional Outcomes in Patients With Acute Ischemic Stroke: An Exploratory Prospective Study

Background Although epigenetic modifications have been expected to play an important role in neuroplasticity for stroke recovery, the role of dynamic microRNA (miRNA) regulation related to functional outcomes after ischemic stroke remains unclear. Therefore, the current study performed a comprehensive miRNA expression analysis in serum to identify specifically altered circulating miRNAs associated with different grades of functional outcomes in patients with acute ischemic stroke (AIS). Methods Twelve patients with AIS in the middle cerebral artery region were included in this study. Peripheral blood samples were collected from patients one or two days after hospitalization. Total RNA, including small RNAs, was extracted from 400 µL of serum, and comprehensive miRNA expression analysis was performed to identify specifically altered circulating miRNAs associated with different grades of functional outcomes. Functional outcomes were evaluated three months after stroke onset using the modified Rankin Scale (mRS), classified as favorable (mRS score of 0 or 1) or unfavorable (mRS score of 2 to 5). Differentially expressed miRNAs were analyzed using the DESeq2 package. Target genes of the miRNAs were explored using miRTargetLink 2.0. Results Acute miRNA expression dynamics were characterized by differences in the patients' functional outcomes following ischemic stroke. The favorable outcome group exhibited significantly downregulated miRNAs, including hsa-miR-218-1, hsa-miR-218-2, hsa-miR-320e, hsa-miR-320d-1, hsa-miR-320d-2, hsa-miR-326, and hsa-miR-4429. In addition, 15 miRNAs, including hsa-miR-223, hsa-miR-18a, hsa-miR-411, and hsa-miR-128-1, were significantly upregulated in the favorable outcome group compared to the unfavorable outcome group. Interesting and strong validated networks between miRNAs and their target genes were identified. Conclusion This study identified specifically altered circulating miRNAs in serum associated with varying grades of functional outcomes in AIS patients and explored miRNA-target gene networks that might contribute to these outcomes. Although further studies are needed, this study highlights their potential role as biomarkers for predicting functional outcomes in patients with AIS.

Endovascular thrombectomy in patients with anterior circulation stroke: an emulated real-world comparison

BACKGROUND

Endovascular thrombectomy (EVT) has been proven effective in anterior circulation stroke due to large vessel occlusion (LVO). However, translation from randomized clinical trials (RCTs) with highly selected patients to real-world requires confirmation, particularly to identify associations outside of strict selection criteria.

AIMS

This study aims to compare functional outcomes after EVT in real-world with those reported in RCTs, and to identify associations with functional outcome after EVT outside RCT-criteria.

METHODS

This study analyzed longitudinal German real-world data from the Stroke Research Consortium in Northern Bavaria (STAMINA) cohort from January, 2015 to June, 2019. We conducted a trial emulation, comparing patients with anterior circulation stroke and LVO meeting selection criteria for RCTs investigating EVT (1) predominantly within 6 hours with those from HERMES meta-analysis, and (2) within 6-24 hours with those from AURORA meta-analysis. We (3) analyzed treatment effects of EVT and association with functional outcome in patients treated outside RCT criteria.

RESULTS

Of 598 patients, 281 (47.0%) met RCT-criteria for treatment within 6 hours (hereinafter STAMINA-HERMES), 74 (12.4%) met RCT-criteria for treatment within 6-24 hours (STAMINA-AURORA), and 277 (46.3%) patients received EVT outside RCT-criteria. We observed no difference in rates of functional independence or mortality, comparing STAMINA-HERMES with HERMES meta-analysis (mRS 0-1: n=120/281 [43%] vs. 291/633 [46%], p=0.36; mortality: n=34/281 [12%] vs. 97/633 [15%], p=0.20), and STAMINA-AURORA with AURORA meta-analysis (mRS 0-1: n=26/74 [35%] vs. 122/266 [46%], p=0.10, mortality: n=10/74 [14%] vs. 45/266 [17%], p=0.48). Patients treated outside RCT-criteria had worse outcome (mRS 0-1: n=38/277 [14%], mortality: n=90/277 [32%], both p<0.001); possibly driven by pre-existing functional dependence (n=172/277 [62%]). Compared to matched controls, EVT outside of RCT-criteria was associated with lower mortality (absolute treatment effect: -14%, 95% Confidence Interval [CI] -23 to -5, p<0.01), but not with recovery to functional independence or premorbid functional status (treatment effect: 4%, CI -4 to 11, p=0.34), which was associated with lower NIHSS (Odds ratio [OR] 0.86, CI 0.80-0.92, p<0.001) and age (OR 0.95, CI 0.93-0.98, p=0.002).

CONCLUSIONS

Translation of EVT outcomes reported in RCTs into real-world is possible, however, almost half of patients did not meet trial criteria. Identification of patients who functionally benefit from frequently performed EVT outside RCT-criteria requires further investigation.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04357899.

S100B and brain ultrasound: Novel predictors for functional outcome in acute ischemic stroke patients

OBJECTIVE

Stroke is a leading cause of mortality and disability worldwide. This study aimed to assess the prognostic value of serum S100B protein, transcranial color-coded duplex sonography (TCCD), and optic nerve sheath diameter (ONSD) in predicting functional outcomes in critically ill patients with acute ischemic stroke (AIS).

METHODS

In this prospective observational study, 80 adult AIS patients were evaluated. Serum S100B protein levels, ONSD, and middle cerebral artery pulsatility index (MCA PI) were measured on days 1 and 3. Functional outcomes at 90 days were assessed using the modified Rankin Scale (mRS) and categorized into favourable (mRS 0-2) or unfavourable (mRS 3-6) groups. The association of demographic, clinical, laboratory, and imaging parameters with mRS outcomes was analyzed.

RESULTS

Poor mRS outcomes occurred in 82.5 % of patients. Factors significantly associated with poor outcomes were female sex, higher National Institutes of Health Stroke Scale (NIHSS) scores on days 1, 3, and 7, and larger stroke size. Receiver Operating Characteristic (ROC) curve analysis revealed that ONSD at days 1 and 3, serum S100B levels at day 1, and right MCA PI at day 1 had significant predictive value for poor mRS outcome. Multivariate analysis identified female sex, S100B on day 1, and NIHSS on days 1, 3, and 7 as independent predictors of poor mRS outcomes.

CONCLUSIONS

The combination of S100B, ONSD, and MCA PI improved the prediction of functional outcomes in critically ill AIS patients. Early S100B measurement and brain ultrasound evaluation may serve as valuable prognostic tools for guiding therapeutic decision-making. This study provides novel insights into the role of S100B and brain ultrasound in stroke outcome prediction, particularly in critically ill AIS patients.

Prognosticating Acute Ischemic Stroke and Estimating the Feasibility of Mapping Stroke Volume to the Functional Outcomes Using Diffusion-Weighted Images: A Systematic Review Protocol

Introduction

Diffusion-weighted image or DWI is commonly used to provide valuable and diverse information on acute stroke in tertiary care hospitals. DWI is a sensitive and accurate method for identifying the infarct core and can expose the area of cerebral infarction within a few hours of onset. This systematic review is planned to evaluate the measurement of stroke volume on DWI and correlate it with functional outcomes (modified ranking scale).

Method

We have adhered to the PRISMA-P checklist to report this systematic review protocol. PubMed, Web of Science, Scopus, and TRIP (Turning Research into Practice) databases will be searched. Two independent reviewers will screen the records, extract data, and critically appraise the studies. A checklist for critical appraisal will be applied for data abstraction, and data extraction will be done using predictive modeling for systematic reviews. The risk of bias will be measured by the Prediction Model Risk of Bias Assessment Tool (PROBAST). The meta-analysis will be considered only if included studies have adequate data, and STATA statistical package version 13.1 will be used for performing a meta-analysis. A narrative synthesis will be performed if meta-analysis is not possible.

Ethics and Dissemination

As this review will focus on secondary information, there is no ethical consideration required. We will disseminate our findings by publishing our analysis in a peer-reviewed journal.

Protocol Registration

In Prospective Register of Systematic Reviews (CRD42019141840).

Influence of Acupuncture and Other Clinical Factors on the Recovery of Limb Motor Function in Patients After Stroke: A Retrospective Study

Background

Limb motor disorders after stroke are very common, and the clinical related factors of improving limb motor function are still unclear. As a part of comprehensive rehabilitation strategy, acupuncture has been widely used in rehabilitation after stroke in China. But more evidence is needed for the influence of acupuncture and some other clinical factors on post-stroke motor disorders.

Patients and Methods

A retrospective study was conducted using the database of patients with post-stroke motor disorders admitted to the Neurological Rehabilitation Unit of the First Teaching Hospital of Tianjin University of Traditional Chinese Medicine. The included patients were grouped according to whether NIHSS improved or muscle strength improved. The positive logistic regression was used to analyze the influencing factors of possible NIHSS improvement. Combined with the influencing factors of NIHSS improvement and muscle strength improvement, the influencing factors of limb motor function recovery after stroke were obtained.

Results

When analyzing the baseline of the included patients, it was found that patients with NIHSS improvement had earlier acupuncture intervention time (M, (IQR):13.5 (14), OR=0.716, 95% CI [0.591-0.869], p=0.001), more cumulative acupuncture treatment times (M,(IQR):29 (12), OR=0.744, 95% CI [0.608-0.910], p=0.004), and less hypertension history (OR=0.256, 95% CI [0.082-0.801], p=0.019). Smoking history only has positive significance in univariate and multivariate analysis of NIHSS, not muscle strength (OR=0.274, 95% CI [0.097-0.779], p=0.015).

Conclusion

The earlier acupuncture intervention and the more cumulative acupuncture treatment times are, the more beneficial the limb function of stroke patients with motor disorders will be. The previous history of hypertension is the influencing factor of limb motor function not improving in patients with limb motor disorder after a stroke. The effect of smoking history on limb movement function of patients with limb motor disorder after stroke needs further study.

A Focus on the Role of DSC-PWI Dynamic Radiomics Features in Diagnosis and Outcome Prediction of Ischemic Stroke

Background: The ability to accurately detect ischemic stroke and predict its neurological recovery is of great clinical value. This study intended to evaluate the performance of whole-brain dynamic radiomics features (DRF) for ischemic stroke detection, neurological impairment assessment, and outcome prediction. Methods: The supervised feature selection (Lasso) and unsupervised feature-selection methods (five-feature dimension-reduction algorithms) were used to generate four experimental groups with DRF in different combinations. Ten machine learning models were used to evaluate their performance by ten-fold cross-validation. Results: In experimental group_A, the best AUCs (0.873 for stroke detection, 0.795 for NIHSS assessment, and 0.818 for outcome prediction) were obtained by outstanding DRF selected by Lasso, and the performance of significant DRF was better than the five-feature dimension-reduction algorithms. The selected outstanding dimension-reduction DRF in experimental group_C obtained a better AUC than dimension-reduction DRF in experimental group_A but were inferior to the outstanding DRF in experimental group_A. When combining the outstanding DRF with each dimension-reduction DRF (experimental group_B), the performance can be improved in ischemic stroke detection (best AUC = 0.899) and NIHSS assessment (best AUC = 0.835) but failed in outcome prediction (best AUC = 0.806). The performance can be further improved when combining outstanding DRF with outstanding dimension-reduction DRF (experimental group_D), achieving the highest AUC scores in all three evaluation items (0.925 for stroke detection, 0.853 for NIHSS assessment, and 0.828 for outcome prediction). By the method in this study, comparing the best AUC of Ft-test in experimental group_A and the best_AUC in experimental group_D, the AUC in stroke detection increased by 19.4% (from 0.731 to 0.925), the AUC in NIHSS assessment increased by 20.1% (from 0.652 to 0.853), and the AUC in prognosis prediction increased by 14.9% (from 0.679 to 0.828). This study provided a potential clinical tool for detailed clinical diagnosis and outcome prediction before treatment.

The Association of Serum Neurofilament Light Chain and Acute Ischaemic Stroke Is Influenced by Effective Revascularization

Objective

To explore associations of serum neurofilament light chain (sNfL) at admission with clinical deficits and the long-term prognosis of acute ischaemic stroke (AIS).

Methods

We recruited 110 AIS patients with serum sampled at hospital arrival. The concentrations of sNfL were detected by a Simoa HD-1 analyser. We first investigated the determinants of sNfL levels at admission within the study population. Associations of sNfL levels with National Institutes of Health Stroke Scale (NIHSS) scores and modified Rankin Scale (mRS) scores were then tested. We further divided the patients into revascularized and nonrevascularized groups, and the associations of sNfL levels with NIHSS and mRS scores were assessed in these subgroups.

Results

Age, sex, stroke history, and the time between the onset of illness and arrival at the hospital were independent influencing factors of sNfL levels within the study population. The sNfL levels at admission were correlated with the NIHSS scores 7 days after stroke (p = 0.004) across all subjects but showed no correlation with the NIHSS scores at admission (p = 0.293) or the mRS scores 6 months after stroke (p = 0.065). Further analysis revealed that in the nonrevascularized group of AIS patients, the sNfL levels at admission were positively correlated with NIHSS scores (NIHSS at admission, p = 0.005; NIHSS 7 days after stroke, p = 0.003) and negatively correlated with mRS scores (p = 0.011).

Conclusion

sNfL levels at admission could be a potential biomarker for predicting clinical deficits and prognosis in the natural course of AIS.

Stroke Core Volume Weighs More Than Recanalization Time for Predicting Outcome in Large Vessel Occlusion Recanalized Within 6 h of Symptoms Onset

Introduction

Current guidelines suggest that perfusion imaging should only be performed > 6 h after symptom onset. Pathophysiologically, brain perfusion should matter whatever the elapsed time. We aimed to compare relative contribution of recanalization time and stroke core volume in predicting functional outcome in patients treated by endovascular thrombectomy within 6-h of stroke-onset.

Methods

Consecutive patients presenting between January 2015 and June 2021 with (i) an acute ischaemic stroke due to an anterior proximal occlusion, (ii) a successful thrombectomy (TICI >2a) within 6-h of symptom-onset and (iii) CT perfusion imaging were included. Core stroke volume was automatically computed using RAPID software. Two linear regression models were built that included in the null hypothesis the pre-treatment NIHSS score and the hypoperfusion volume (Tmax > 6 s) as confounding variables and 24 h post-recanalization NIHSS and 90 days mRS as outcome variables. Time to recanalization was used as covariate in one model and stroke core volume as covariate in the other.

Results

From a total of 377 thrombectomies, 94 matched selection criteria. The Model null hypothesis explained 37% of the variability for 24 h post-recanalization NIHSS and 42% of the variability for 90 days MRS. The core volume as covariate increased outcome variability prediction to 57 and 56%, respectively. Time to recanalization as covariate marginally increased outcome variability prediction from 37 and 34% to 40 and 42.6%, respectively.

Conclusion

Core stroke volume better explains outcome variability in comparison to the time to recanalization in anterior large vessel occlusion stroke with successful thrombectomy done within 6 h of symptoms onset. Still, a large part of outcome variability prediction fails to be explained by the usual predictors.

Predictors of stroke favorable functional outcome in Guinea, results from the Conakry stroke registry

Low- to middle-income countries (LMICs) now bear most of the stroke burden. In LMICs, stroke epidemiology and health care systems are different from HICs. Therefore, a high-income country (HIC)-based predictive model may not correspond to the LMIC stroke context. Identify the impact of modifiable variables in acute stroke management in Conakry, Guinea as potential predictors of favorable stroke outcome. Data were extracted from the Conakry stroke registry that includes 1018 patients. A logistic regression model was built to predict favorable stroke outcomes, defined as mRS 0–2. Age, admission NIHSS score, mean arterial blood pressure and capillary glycemia were chosen as covariates. Delay to brain CT imaging under 24 h from symptom onset, fever, presence of sores and abnormal lung auscultation were included as factors. NIHSS score on admission, age and ischemic stroke were included in the null model as nuisance parameters to determine the contribution of modifiable variables to predict stroke favorable outcome. Lower admission NIHSS, brain CT imaging within 24 h of symptoms onset and lower mean arterial blood pressure emerged as a significant positive predictors of favorable stroke outcome with respective odd ratios (OR) of 1.35 [1.28–1.43], 2.1 [1.16–3.8] and 1.01 [1.01–1.04]. The presence of fever or sores impacted negatively stroke favorable outcomes with OR of 0.3 [0.1–0.85] and 0.25 [0.14–0.45]. The area under receiver operating characteristic curves (AUC) of the model was 0.86. This model explained 44.5% of the variability of the favorable stroke outcome with 10.2% of the variability explained by the modifiable variables when admission NIHSS, and ischemic stroke were included in the null model as nuisance parameter. In the Conakry stroke registry, using a logistic regression to predict stroke favorable outcome, five variables that led to an AUC of 0.86: admission NIHSS, early brain CT imaging, fever, sores and mean blood pressure. This paves the way for future public health interventions to test whether modulating amendable variables leads to increased favorable stroke outcomes in LMICs.

Frailty is an outcome predictor in patients with acute ischemic stroke receiving endovascular treatment

INTRODUCTION

Frailty is a disorder of multiple physiological systems impairing the capacity of the organism to cope with insult or stress. It is associated with poor outcomes after acute illness. Our aim was to study the impact of frailty on the functional outcome of patients with acute ischemic stroke (AIS) submitted to endovascular stroke treatment (EST).

METHODS

We performed a retrospective study of patients with AIS of the anterior circulation submitted to EST between 2012 and 2017, based on a prospectively collected local registry of consecutive patients. The Hospital Frailty Risk Score (HFRS) at discharge was calculated for each patient. We compared groups of patients with and without favourable 3-month outcome after index AIS (modified Rankin Scale 0-2 and 3-6, respectively). A multivariable logistic regression model was used to identify variables independently associated with favourable 3-month outcome. Diagnostic test statistics were used to compare HFRS with other prognostic scores for AIS.

RESULTS

We included 489 patients with median age 75.6 years (interquartile range [IQR] = 65.3-82.3) and median NIHSS 15 (IQR = 11-19). About 29.7% presented a high frailty risk (HFRS >15 points). Patients with favourable 3-month outcome presented lower HFRS and lower prevalence of high frailty risk. High frailty risk was independently associated with decreased likelihood of favourable 3-month outcome (adjusted odds ratio = 0.48, 95% confidence interval = 0.26-0.89). Diagnostic performances of HFRS and other prognostic scores (THRIVE and PRE scores, SPAN-100 index) for outcome at 3-months were similar.

DISCUSSION

Frailty is an independent predictor of outcome in AIS patients submitted to EST.

Diffusion MRI tractography for neurosurgery: the basics, current state, technical reliability and challenges

Diffusion magnetic resonance imaging (dMRI) tractography is currently the only imaging technique that allows for non-invasive delineation and visualisation of white matter (WM) tractsin vivo,prompting rapid advances in related fields of brain MRI research in recent years. One of its major clinical applications is for pre-surgical planning and intraoperative image guidance in neurosurgery, where knowledge about the location of WM tracts nearby the surgical target can be helpful to guide surgical resection and optimise post-surgical outcomes. Surgical injuries to these WM tracts can lead to permanent neurological and functional deficits, making the accuracy of tractography reconstructions paramount. The quality of dMRI tractography is influenced by many modifiable factors, ranging from MRI data acquisition through to the post-processing of tractography output, with the potential of error propagation based on decisions made at each and subsequent processing steps. Research over the last 25 years has significantly improved the anatomical accuracy of tractography. An updated review about tractography methodology in the context of neurosurgery is now timely given the thriving research activities in dMRI, to ensure more appropriate applications in the clinical neurosurgical realm. This article aims to review the dMRI physics, and tractography methodologies, highlighting recent advances to provide the key concepts of tractography-informed neurosurgery, with a focus on the general considerations, the current state of practice, technical challenges, potential advances, and future demands to this field.

The association between telomere length and ischemic stroke risk and phenotype

The chronological age of a person is a key determinant of etiology and prognosis in the setting of ischemic stroke. Telomere length, an indicator of biological aging, progressively shortens with every cell cycle. Herein, we determined telomere length from peripheral blood leukocytes by Southern blot analyses in a prospective cohort of ischemic stroke patients (n = 163) and equal number of non-stroke controls and evaluated its association with various ischemic stroke features including etiology, severity, and outcome. A shorter telomere length (i.e. lowest quartile; ≤ 5.5 kb) was significantly associated with ischemic stroke (OR 2.95, 95% CI 1.70–5.13). This significant relationship persisted for all stroke etiologies, except for other rare causes of stroke. No significant association was present between admission lesion volume and telomere length; however, patients with shorter telomeres had higher admission National Institutes of Health Stroke Scale scores when adjusted for chronological age, risk factors, etiology, and infarct volume (p = 0.046). On the other hand, chronological age, but not telomere length, was associated with unfavorable outcome (modified Rankin scale > 2) and mortality at 90 days follow-up. The association between shorter telomere length and more severe clinical phenotype at the time of admission, might reflect reduced resilience of cerebral tissue to ischemia as part of biological aging.

Modeling and simulation to predict the degree of disability over time in acute ischemic stroke patients

Disability in patients with acute stroke varies over time, with the prediction of outcomes being critical for proper management. This study aimed to develop a model to predict the cumulative probability of each modified Rankin Scale (mRS) score over time with inclusion of significant covariates. Longitudinal data obtained from 193 patients, 1–24 months after onset of acute ischemic stroke, were included for a modeling analysis using nonlinear mixed‐effect modeling (NONMEM). After selecting a model that best described the time course of the probability of different mRS scores, potential covariates were tested. Visual predicted check plots, parameter estimates, and decreases in minimum objective function values were used for model evaluation. The inclusion of disease progression (DP) in the baseline proportional odds cumulative logit model significantly improved the model compared to the baseline model without DP. An inhibitory maximum effect (E_max) model was determined to be the best DP model for describing the probability of specific mRS scores over time. In the final model, DP was multiplied with the baseline cumulative logit probability with a baseline adjustment. In addition to differences in lesion volume (DLV), the final model included comorbid diabetes mellitus (DM) and baseline National Institutes of Health Stroke Scale (NIHSS) scores on E_max as statistically significant covariates. This study developed a model including DLV, NIHSS score, and comorbid DM for predicting the disability time course in patients with acute ischemic stroke. This model may help to predict disease outcomes and to develop more appropriate management plans for patients with acute stroke.

EASY score (Eloquent, Age and baseline SYmptoms score) for outcome prediction in patients with acute ischemic stroke

OBJECTIVE

A pragmatic tool for the early and reliable prediction of recovery in patients with acute ischemic stroke is needed. We aimed to test the addition of brain eloquent areas involvement in variables predicting poor outcome, using a simple scoring system.

METHODS

Retrospective study of patients with anterior circulation acute ischemic stroke treated with best medical treatment and/or endovascular reperfusion. Primary outcome measure was 3-months poor outcome (mRs 3-6). We developed a prognostic model based on clinical data and a quantitative scoring system of the main eloquent brain areas involved on early follow-up CT, and analyzed its accuracy to predict poor outcome comparatively to three other prognostic models. The final model was used to develop a score for outcome prediction based on the multivariable analysis.

RESULTS

A total of 197 patients were included (poor outcome = 62; mean age 67 ± 15.1 years; 44% females). Independent predictors of poor outcome were increasing age (p < 0.001), baseline NIHSS (p = 0.03), and the involvement of two brain areas: posterior limb of internal capsule (p < 0.001) and postero-superior corona radiata (p < 0.001). This model showed to be the most accurate to predict poor outcome (Balance Accuracy = 77.74%; C-Statistic = 0.891). The derived risk score attributing points for each of these variables (EASY score) showed similar performances (Balance Accuracy = 82.11%; C-Statistic = 0.90).

CONCLUSION

The EASY score is an easy-to-apply and accurate tool to predict the 3-months functional outcome after ischemic stroke, relying on simple clinical features and the assessment of two key eloquent brain areas on early follow-up CT.

Multimodal CT pc-ASPECTS in infratentorial stroke: diagnostic and prognostic value

BACKGROUND AND PURPOSE

Diagnosis of posterior circulation stroke may be challenged. National Institutes of Health Stroke Scale (NIHSS) and brain imaging (non-contrast brain computed tomography-CT) are used for diagnosis; evaluation on posterior circulation stroke remains a limit of NIHSS, and the value of non-contrast CT (NCCT) is limited due to artifacts caused by the bones of the base of the skull. We tested the validity and prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) in patients with posterior circulation stroke.

METHODS

Pc-ASPECTS allots the posterior circulation 10 points. We studied 50 patients with posterior circulation stroke. We applied pc-ASPECTS to NCCT, CT angiography, and CT Perfusion. We evaluated the correlation of pc-ASPECT with outcome parameters for stroke.

RESULTS

Out of 50 patients, CTP showed abnormalities in 34 cases. The pc-ASPECT score calculated on brain CT and on the brain CT + angio CT had a sensibility of 24%, calculated on brain CT, angio CT and CTPerfusion gain a sensibility of 72%. Pc-ASPECT MTT resulted to be the more reliable parameter: outcome given by NIHSS score at discharge, mRS at discharge, and at 3 months was more severe in patients with Pc-ASPECT MTT alteration. Outcome given by NIHSS score at discharge and mRS at discharge and 1 at 3 months was more severe in patients with higher NIHSS score at admission.

CONCLUSION

We evaluated the usefulness of pc-ASPECTS on CTP in predicting functional outcome in acute posterior circulation stroke that appears to be a powerful marker for predicting functional outcome.

Cilostazol Addition to Aspirin could not Reduce the Neurological Deterioration in TOAST Subtypes: ADS Post-Hoc Analysis

BACKGROUND

Our previous trial acute dual study (ADS) reported that dual antiplatelet therapy (DAPT) using cilostazol and aspirin did not reduce the rate of short-term neurological worsening in non-cardioembolic stroke patients. Present post-hoc analysis investigated whether the impact of combined cilostazol and aspirin differed among stroke subtypes and factors associated with neurological deterioration and/or stroke recurrence.

METHODS

Using the ADS registry, the rate of neurological deterioration, defined as clinical worsening and/or recurrent stroke, including transient ischemic attack was calculated. Stroke subtypes included large-artery atherosclerosis (LAA), small vessel occlusion (SVO), other determined etiology (Others), and undetermined etiology of stroke (Undetermined).

RESULTS

Data of 1022 patients were analyzed. Deterioration was seen in 104 (10%) patients, and the rates were not markedly different between patients treated with DAPT vs. aspirin in any stroke subtypes: LAA, 19% vs. 11%, (p=0.192); SVO, 10% vs. 10% (p=1.000); Others, 6% vs. 6% (p=1.000); Undetermined, 11% vs. 8% (p=0.590). Diabetes mellitus was the independent factor associated with deterioration (odds ratio 4.360, 95% confidence interval 1.139-16.691, p=0.032) in the LAA group. Age (1.030 [1.004-1.057], p=0.026), systolic blood pressure (1.012 [1.003-1.022], p=0.010), and infarct size (2.550 [1.488-4.371], p=0.001) were associated with deterioration in SVO group, and intracranial stenosis/occlusion was associated with it in the Undetermined group (3.744 [1.138-12.318], p=0.030).

CONCLUSIONS

Combined cilostazol and aspirin did not reduce the rate of short-term neurological deterioration in any clinical stroke subtype. The characteristics of patients whose condition deteriorates in the acute period may differ based on the stroke subtypes.

Prognostic yield of imaging before and after recanalization treatments in ischemic stroke

OBJECTIVES

The scores to predict outcome in ischemic stroke were validated prior to the approval of modern revascularization treatments. We evaluated the accuracy of pre and post-treatment models in a recent recanalization therapy cohort and whether radiological and ultrasound findings could improve their accuracy.

MATERIAL & METHODS

We included 375 anterior circulation ischemic stroke patients treated with intravenous thrombolysis or thrombectomy during 2017 and 2018. We collected demographic, clinical, and imaging data. We built pre and post-treatment logistic regression models to predict independence (modified Rankin Scale 0-2) at 3 months. The models included the Alberta Stroke Program Early CT Score (ASPECTS), infarct volume (ABC/2 method), and the Thrombolysis in Brain Ischemia (TIBI) ultrasonographic grade of recanalization. We compared areas under the receiver operating characteristic curve (AUC).

RESULTS

Our preintervention model, combining neurological deficit severity, age, and admission glycemia, was not improved by the inclusion of ASPECTS (AUC 0.80 vs 0.79, P = .28). Early neurological recovery at 24-hour significantly increased prognostic performance (AUC = 0.85, P < .01), which did not change by adding final infarct volume or the persistence of arterial occlusion of the affected territory (AUC = 0.86 and 0.85, P > .05).

CONCLUSIONS

Models that combine simple variables such as neurological deficit severity, age, and admission glycemia were the most useful for predicting functional outcome in ischemic stroke patients submitted to revascularization treatments. Pre and post-treatment imaging findings did not enhance prognostic accuracy when compared to the patient's clinical improvement.

Individualized Prediction Of Stroke-Associated Pneumonia For Patients With Acute Ischemic Stroke

Background

Stroke-associated pneumonia (SAP) is a serious and common complication in stroke patients.

Purpose

We aimed to develop and validate an easy-to-use model for predicting the risk of SAP in acute ischemic stroke (AIS) patients.

Patients and methods

The nomogram was established by univariate and multivariate binary logistic analyses in a training cohort of 643 AIS patients. The prediction performance was determined based on the receiver operating characteristic curve (ROC) and calibration plots in a validation cohort (N=340). Individualized clinical decision-making was conducted by weighing the net benefit in each AIS patient by decision curve analysis (DCA).

Results

Seven predictors, including age, NIHSS score on admission, atrial fibrillation, nasogastric tube intervention, mechanical ventilation, fibrinogen, and leukocyte count were incorporated to construct the nomogram model. The nomogram showed good predictive performance in ROC analysis [AUROC of 0.845 (95% CI: 0.814-0.872) in training cohort, and 0.897 (95% CI: 0.860-0.927) in validation cohort], and was superior to the A²DS², ISAN, and PANTHERIS scores. Furthermore, the calibration plots showed good agreement between actual and nomogram-predicted SAP probabilities, in both training and validation cohorts. The DCA confirmed that the SAP nomogram was clinically useful.

Conclusion

Our nomogram may provide clinicians with a simple and reliable tool for predicting SAP based on routinely available data. It may also assist clinicians with respect to individualized treatment decision-making for patients differing in risk level.

Biomarkers of immune capacity, infection and inflammation are associated with poor outcome and mortality after stroke - the PREDICT study

Background

Almost 40% of stroke patients have a poor outcome at 3 months after the index event. Predictors for stroke outcome in the early acute phase may help to tailor stroke treatment. Infection and inflammation are considered to influence stroke outcome.

Methods

In a prospective multicenter study in Germany and Spain, including 486 patients with acute ischemic stroke, we used multivariable regression analysis to investigate the association of poor outcome with monocytic HLA-DR (mHLA-DR) expression, interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-alpha) and lipopolysaccharide-binding protein (LBP) as markers for immunodepression, inflammation and infection. Outcome was assessed at 3 months after stroke via a structured telephone interview using the modified Rankin Scale (mRS). Poor outcome was defined as a mRS score of 3 or higher which included death. Furthermore, a time-to-event analysis for death within 3 months was performed.

Results

Three-month outcome data was available for 391 patients. Female sex, older age, diabetes mellitus, atrial fibrillation, stroke-associated pneumonia (SAP) and higher National Institute of Health Stroke Scale (NIHSS) score as well as lower mHLA-DR levels, higher IL-6 and LBP-levels at day 1 were associated with poor outcome at 3 months in bivariate analysis. Furthermore, multivariable analysis revealed that lower mHLA-DR expression was associated with poor outcome.

Female sex, older age, atrial fibrillation, SAP, higher NIHSS score, lower mHLA-DR expression and higher IL-6 levels were associated with shorter survival time in bivariate analysis. In multivariable analysis, SAP and higher IL-6 levels on day 1 were associated with shorter survival time.

Conclusions

SAP, lower mHLA-DR-expression and higher IL-6 levels on day one are associated with poor outcome and shorter survival time at 3 months after stroke onset.

Trial registration

www.clinicaltrials.gov, NCT01079728, March 3, 2010.

Clinical characteristics and risk score for poor clinical outcome of acute ischemic stroke patients treated with intravenous thrombolysis therapy

BACKGROUND

Tissue plasminogen activator (t-PA) is an effective therapy for acute ischemic stroke, but some patients still have poor clinical outcome. In this study, we investigated clinical characteristics of stroke patients and determined predictors for poor clinical outcome in response to t-PA treatment.

METHODS

Clinical data from 247 patients were retrospectively reviewed. Clinical parameters that were associated with survival of patients were analyzed. Areas under receiver operating characteristic curves (ROC) were used to determine the feasibility of using various combinations of the clinical parameters to predict poor clinical response. The clinical outcome was defined according to the changes in Modified Rankin Scale.

RESULTS

Overall, 145 patients had improved/complete recovery, 73 had no change, and 29 had worsening conditions or died during the in-clinic period. A univariate analysis showed that baseline characteristics including age, CRP, blood glucose level, systolic blood pressure, and admission NIHSS were significantly different (p < 0.05) among patients with different clinical outcome. A further multivariate analysis was then performed. Variables associated with poor clinical outcome (worsening/death) (p < 0.1) were included in the logistic regression model. Four parameters were retained in the model: Age, CRP, Blood glucose level, and Systolic blood pressure (ACBS). To allow a convenient usage of the ACBS classifier, the parameters were put into a scoring system, and the score at 7.7 was chosen as a cut-off. The ROC curve of this ACBS classifier has an area under the curve (AUC) of 0.7788, higher than other individual parameters. The ACBS classifier provided enhanced sensitivity of 69.2% and specificity of 74.3%.

CONCLUSION

The ACBS classifier provided a satisfactory power in estimating the patients' clinical outcome. After further validating, the classifier may provide important information to clinicians for making clinical decisions.

Prognostic Value of Cystatin C in Acute Ischemic Stroke Patients with Intravenous Thrombolysis

BACKGROUND

Less is known about the prognostic value of serum cystatin C in acute ischemic stroke (AIS) patients treated with intravenous thrombolysis (IVT). The aim of the present study was to examine the association between serum cystatin C levels and prognosis of AIS patients after IVT.

METHODS

Serum cystatin C was measured within 24 hours after recombinant tissue plasminogen activator (rt-PA) treatment in 280 consecutively recruited patients with AIS. The main outcomes included combination of death and major disability, death, major disability (modified Rankin Scale score 3-5) and vascular events at 3-month follow-up.

RESULTS

During the 3-month follow-up, 94 patients (33.6%) experienced death or major disability (28 deaths and 66 major disability) and 49 patients (17.5%) experienced vascular events. After multivariate adjustment, serum cystatin C was significantly associated with an increased risk of the combined outcome of death and major disability (OR=4.51, P = 0.006). Adding serum cystatin C quartiles to a model containing conventional risk factors improved the predictive power for the combined outcome of death and major disability (continuous net reclassification index 43.88%, P < 0.001; categorical net reclassification index 9.15%, P = 0.013; integrated discrimination improvement 2.31%, P = 0.025). Similar phenomena were also observed in major disability and vascular events.

CONCLUSION

Higher levels of serum cystatin C in AIS patients after IVT were independently associated with increased risks of poor functional outcomes and vascular events, especially combining conventional risk factors, suggesting that serum cystatin C might improve risk prediction for poor prognosis in AIS patients receiving rt-PA treatment.

Derivation of a Prediction Rule for Unfavorable Outcome after Ischemic Stroke in the Chinese Population

BACKGROUND

Efficient assessment of patients after ischemic stroke has important reference value for doctors to choose appropriate treatment for patients. Our study aimed to develop a new prognostic model for predicting outcomes 3 months after ischemic stroke among Chinese Population.

METHODS

A prospective observational cohort study among ischemic stroke patients presenting to Emergency Department in the Second Affiliated Hospital of Guangzhou Medical University was conducted from May 2012 to June 2013. Demographic data of ischemic stroke patients, assessment of NIHSS and laboratory results were collected. Based on 3-month modified Rankin Scale (mRS) ischemic stroke patients were divided into either favorable outcome (mRS: 0-2) or unfavorable outcome groups (mRS: 3-6). The variables closely associated with prognosis of ischemic stroke were selected to develop the new prognostic model (NAAP) consisted of 4 parameters: NIHSS, age, atrial fibrillation, and prealbumin. The prognostic value of the modified prognostic model was then compared with NIHSS alone.

RESULTS

A total of 454 patients with suspected stroke were recruited. One hundred eighty-six patients with ischemic stroke were included in the final analysis. A new prognostic model, NAAP was developed. The area under curve (AUC) of NAAP was .861 (95%confidence interval: .803-.907), whilst the AUC of NIHSS was .783 (95%CI: .717-.840), (P = .0048). Decision curve analysis showed that NAAP had a higher net benefit for threshold probabilities of 65% for predictive risk of poor outcomes.

CONCLUSIONS

The modified prognostic model, NAAP may be a better prognostic tool for predicting 3-month unfavorable outcomes for ischemic stroke than NIHSS alone.

Serum neurofilament light: A biomarker of neuroaxonal injury after ischemic stroke

OBJECTIVE

To explore the utility of serum neurofilament light chain (NfL) as a biomarker for primary and secondary neuroaxonal injury after ischemic stroke (IS) and study its value for the prediction of clinical outcome.

METHODS

We used an ultrasensitive single-molecule array assay to measure serum NfL levels in healthy controls (n = 30) and 2 independent cohorts of patients with IS: (1) with serial serum sampling at hospital arrival (n = 196), at days 2, 3, and 7 (n = 89), and up to 6 months post stroke; and (2) with standardized MRI at baseline and at 6 months post stroke, and with cross-sectional serum sampling at 6 months (n = 95). We determined the temporal profile of serum NfL levels, their association with imaging markers of neuroaxonal injury, and with clinical outcome.

RESULTS

Patients with IS had higher serum NfL levels compared with healthy controls starting from admission until 6 months post stroke. Serum NfL levels peaked at day 7 (211.2 pg/mL [104.7-442.6], median [IQR]) and correlated with infarct volumes (day 7: partial r = 0.736, p = 1.5 × 10^-15). Six months post stroke, patients with recurrent ischemic lesions on MRI (n = 19) had higher serum NfL levels compared to those without new lesions (n = 76, p = 0.002). Serum NfL levels 6 months post stroke further correlated with a quantitative measure of secondary neurodegeneration obtained from diffusion tensor imaging MRI (r = 0.361, p = 0.001). Serum NfL levels 7 days post stroke independently predicted modified Rankin Scale scores 3 months post stroke (cumulative odds ratio [95% confidence interval] = 2.35 [1.60-3.45]; p = 1.24 × 10^-05).

CONCLUSION

Serum NfL holds promise as a biomarker for monitoring primary and secondary neuroaxonal injury after IS and for predicting functional outcome.

ASPECTS-based reperfusion status on arterial spin labeling is associated with clinical outcome in acute ischemic stroke patients

The purpose of this study was to develop and evaluate a scoring system for assessing reperfusion status based on arterial spin labeled (ASL) perfusion MRI in acute ischemic stroke (AIS) patients receiving thrombolysis and/or endovascular treatment. Pseudo-continuous ASL with background suppressed 3D GRASE was acquired along with DWI in 90 patients within 24 h post-treatment. An automatic reperfusion scoring system (auto-RPS) was devised based on the Alberta Stroke Program Early CT Score (ASPECTS) template, and compared with manual RPS and DWI-ASPECTS. TICI (thrombolysis in cerebral infarction) scores were graded in 48 patients who received endovascular treatment. Favorable outcomes were defined by a modified Rankin Scale score of 0-2 at three months. Auto-RPS was positively correlated with DWI-ASPECTS (ρ = 0.6, P < 0.001) and was on average 1 point lower than DWI-ASPECTS ( P < 0.001). The area under the receiver operating characteristic curve for discriminating poor functional outcome (n = 90) was 0.75 (95% CI, 0.64-0.86) for manual RPS, 0.85 (95% CI, 0.76-0.94) for auto-RPS, and 0.81 (95% CI, 0.71-0.90) for DWI-ASPECTS. Multiple logistic regression analysis in the TICI-graded patients (n = 48) showed that auto-RPS is highly associated with functional outcome (OR = 25.2, 95% CI 4.02-496, P < 0.01). Post treatment auto-RPS within 24 h provides a useful tool to predict functional outcome in AIS patients.

The Role of Serum Ferritin, Pro-Brain Natriuretic Peptide and Homocysteine Levels in Determining Ischaemic Stroke Subtype, Severity and Mortality

Background

In ischaemic stroke, there are many biochemical and immunological reactions secondary to a reduced cerebral blood flow. The purpose of this study is to investigate the correlation between stroke subtype, stroke severity, mortality, and serum ferritin, pro-brain natriuretic peptide (pro-BNP), homocysteine values before a specific treatment is given to stroke patients in the emergency department.

Methods

Consecutive acute ischaemic stroke patients admitted between December 2007 and April 2008 were enrolled into the study. Serum ferritin, pro-BNP and homocysteine levels were studied before specific treatment was carried out. Stroke subtypes were determined according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) and Oxfordshire Community Stroke Project (OCSP) criteria. The severity of stroke was determined by the National Institutes of Health Stroke Scale (NIHSS). Fifteen healthy individuals who matched the study group in terms of sex and age were chosen as control.

Results

Ninety-two patients were included in the study. There was a significant difference in the serum ferritin, pro-BNP and homocysteine levels between patients who died and those who survived (p=0.013, p<0.001 and p=0.003 respectively). Serum ferritin, pro-BNP and homocysteine levels were higher in all stroke subtypes than in the control group. Comparing among stroke subtypes, only serum pro-BNP levels were higher in the cardioembolic stroke group than in the atherothrombotic stroke and lacunar stroke groups (p=0.003 and p<0.001 respectively); and only serum pro-BNP levels were higher in the total anterior circulation infarct group than in the posterior circulation infarct and lacunar infarct groups (p=0.010 and p=0.017 respectively). Pro-BNP levels were significantly higher in patients with NIHSS score >15 than NIHSS=8-15 and NIHSS=1-7 (p=0.016 and p<0.001 respectively).

Conclusion

Ferritin, pro-BNP and homocysteine levels were raised in acute ischaemic stroke patients. However, only serum pro-BNP level is clinically useful in predicting stroke subtype, severity and mortality that could provide an insight to the choice of treatment.

Early Rehabilitation After Stroke: a Narrative Review

PURPOSE OF REVIEW

Despite current rehabilitative strategies, stroke remains a leading cause of disability in the USA. There is a window of enhanced neuroplasticity early after stroke, during which the brain's dynamic response to injury is heightened and rehabilitation might be particularly effective. This review summarizes the evidence of the existence of this plastic window, and the evidence regarding safety and efficacy of early rehabilitative strategies for several stroke domain-specific deficits.

RECENT FINDINGS

Overall, trials of rehabilitation in the first 2 weeks after stroke are scarce. In the realm of very early mobilization, one large and one small trial found potential harm from mobilizing patients within the first 24 h after stroke, and only one small trial found benefit in doing so. For the upper extremity, constraint-induced movement therapy appears to have benefit when started within 2 weeks of stroke. Evidence for non-invasive brain stimulation in the acute period remains scant and inconclusive. For aphasia, the evidence is mixed, but intensive early therapy might be of benefit for patients with severe aphasia. Mirror therapy begun early after stroke shows promise for the alleviation of neglect. Novel approaches to treating dysphagia early after stroke appear promising, but the high rate of spontaneous improvement makes their benefit difficult to gauge. The optimal time to begin rehabilitation after a stroke remains unsettled, though the evidence is mounting that for at least some deficits, initiation of rehabilitative strategies within the first 2 weeks of stroke is beneficial. Commencing intensive therapy in the first 24 h may be harmful.

The Impact of Discrepancy between Measured versus Stated Weight on Hemorrhagic Transformation and Clinical Outcomes after Intravenous Alteplase Thrombolysis

BACKGROUND

An accurate measurement of patient weight is important in determining the dosage for intravenous alteplase thrombolysis. In most emergency rooms, however, weight is not measured. We investigated the difference between stated and measured weight and its effect on hemorrhagic transformation and clinical outcomes.

METHODS

We enrolled 128 consecutive patients who had hyperacute stroke and were treated by alteplase. Alteplase dose was calculated using the weight provided by patient or guardian/caregiver, and the actual weight was measured after administration. Patients were classified into 2 groups: overused group (stated weight >measured weight) and underused group (measured weight ≥stated weight). The prevalence of hemorrhagic transformation on follow-up, determined by gradient-recalled echo MRI or non-enhanced CT, was compared between the 2 groups. The predictors for hemorrhage with progression, defined as an increase in the National Institutes of Health Stroke Scale (NIHSS) by a value of 4 or more accompanied by hemorrhage, were determined using multivariable logistic regression analysis and included the overused or underused alteplase and baseline clinical and laboratory findings.

RESULTS

Sixty-six (51.6%) of 128 patients were in the underused group and 62 patients (48.4%) in the overused group. The median difference between the stated and measured weights was 1.5 (interquartile range 0.56-3.81) kg, with the largest difference being 25.6 kg. Although there were no significant difference in baseline clinical and laboratory findings between the 2 groups, the overused group showed a significantly higher prevalence of hemorrhagic transformation (p = 0.012) and hemorrhage with progression (p = 0.025). The multivariable logistic regression analysis demonstrated that overused alteplase (OR 7.26; 95% CI 1.24-42.45; p = 0.028), baseline glucose (>144 mg/dL; OR 5.03; 95% CI 1.00-25.26; p = 0.050), and initial NIHSS (OR 1.13 per 1-point NIHSS increase; 95% CI 1.00-1.27; p = 0.047) in model 1 that use alteplase overdose as a categorical variable and overused alteplase (OR 1.67 1-mg increase; 95% CI 1.05-2.66; p = 0.027) in model 2 that use an overused alteplase dose as numerical variable were significant predictors for hemorrhage with progression.

CONCLUSION

More alteplase usage than actual weight led to higher hemorrhagic transformation. As one of the predictors for clinical deterioration, it is important to administrate alteplase based on an accurately measured weight.

The Role of Imaging in Clinical Stroke Scales That Predict Functional Outcome: A Systematic Review

BACKGROUND AND PURPOSE

Numerous stroke scales have been developed to predict functional outcomes following acute ischemic stroke. The goal of this study was to summarize functional outcome scores in stroke that incorporate neuroimaging with those that don't incorporate neuroimaging.

METHODS

Searches were conducted in Ovid MEDLINE, Ovid Embase, and the Cochrane Library Database from inception to January 23, 2015. Additional records were identified by employing the "Cited by" and "View References" features in Scopus. We included studies that described stroke prognosis models or scoring systems that predict functional outcome based on clinical and/or imaging data available on presentation. Score performance was evaluated based on area under the receiver operating characteristic curve (AUC).

RESULTS

A total of 3300 articles were screened, yielding 14 scores that met inclusion criteria. Half (7) of the scores included neuroimaging as a predictor variable. Neuroimaging parameters included infarct size on magnetic resonance diffusion-weighted imaging, infarct size defined by computed tomography hypodensity, and hemodynamic abnormality on perfusion imaging. The modified Rankin Scale at 3 months poststroke was the most common functional outcome reported (13 of 14 scores). The AUCs ranged from 0.64 to 0.84 for scores that included neuroimaging as a predictor and 0.64 to 0.94 for scores that did not include neuroimaging. External validation has been performed for 7 scores.

CONCLUSIONS

Due to the marked heterogeneity in the scores and populations in which they were applied, it is unclear whether current imaging-based scores offer advantages over simpler approaches for predicting poststroke function.

Astrocyte-specific insulin-like growth factor-1 gene transfer in aging female rats improves stroke outcomes

Middle aged female rats sustain larger stroke infarction and disability than younger female rats. This older group also shows age-related reduction of insulin like growth factor (IGF)-1 in serum and in astrocytes, a cell type necessary for poststroke recovery. To determine the impact of astrocytic IGF-1 for ischemic stroke, these studies tested the hypothesis that gene transfer of IGF-1 to astrocytes will improve stroke outcomes in middle aged female rats. Middle aged (10-12 month old), acyclic female rats were injected with recombinant adeno-associated virus serotype 5 (AAV5) packaged with the coding sequence of the human (h)IGF-1 gene downstream of an astrocyte-specific promoter glial fibrillary acidic protein (GFAP) (AAV5-GFP-hIGF-1) into the striatum and cortex. The AAV5-control consisted of an identical shuttle vector construct without the hIGF-1 gene (AAV5-GFAP-control). Six to eight weeks later, animals underwent transient (90 min) middle cerebral artery occlusion via intraluminal suture. While infarct volume was not altered, AAV5-GFAP-hIGF-1 treatment significantly improved blood pressure and neurological score in the early acute phase of stroke (2 days) and sensory-motor performance at both the early and late (5 days) acute phase of stroke. AAV5-GFAP-hIGF-1 treatment also reduced circulating serum levels of GFAP, a biomarker for blood brain barrier permeability. Flow cytometry analysis of immune cells in the brain at 24 hr poststroke showed that AAV5-GFAP-hIGF-1 altered the type of immune cells trafficked to the ischemic hemisphere, promoting an anti-inflammatory profile. Collectively, these studies show that targeted enhancement of IGF-1 in astrocytes of middle-aged females improves stroke-induced behavioral impairment and neuroinflammation.

A statistical model for stroke outcome prediction and treatment planning

Stroke is a major cause of mortality and long-term disability in the world. Predictive outcome models in stroke are valuable for personalized treatment, rehabilitation planning and in controlled clinical trials. We design a new multi-class classification model to predict outcome in the short-term, the putative therapeutic window for several treatments. Our model addresses the challenges of class imbalance, where the training data is dominated by samples of a single class, and highly correlated predictor and outcome variables, which makes learning the effects of treatments on the outcome difficult. Empirically our model outperforms the best-known previous predictive models and can infer the most effective treatments in improving outcome that have been independently validated in clinical studies.

Stroke unit care in germany: the german stroke registers study group (ADSR)

BACKGROUND

Factors influencing access to stroke unit (SU) care and data on quality of SU care in Germany are scarce. We investigated characteristics of patients directly admitted to a SU as well as patient-related and structural factors influencing adherence to predefined indicators of quality of acute stroke care across hospitals providing SU care.

METHODS

Data were derived from the German Stroke Registers Study Group (ADSR), a voluntary network of 9 regional registers for monitoring quality of acute stroke care in Germany. Multivariable logistic regression analyses were performed to investigate characteristics influencing direct admission to SU. Generalized Linear Mixed Models (GLMM) were used to estimate the influence of structural hospital characteristics (percentage of patients admitted to SU, year of SU-certification, and number of stroke and TIA patients treated per year) on adherence to predefined quality indicators.

RESULTS

In 2012 180,887 patients were treated in 255 hospitals providing certified SU care participating within the ADSR were included in the analysis; of those 82.4% were directly admitted to a SU. Ischemic stroke patients without disturbances of consciousness (p < .0001), an interval onset to admission time ≤3 h (p < .0001), and weekend admission (p < .0001) were more likely to be directly admitted to a SU. A higher proportion of quality indicators within predefined target ranges were achieved in hospitals with a higher proportion of SU admission (p = 0.0002). Quality of stroke care could be maintained even if certification was several years ago.

CONCLUSIONS

Differences in demographical and clinical characteristics regarding the probability of SU admission were observed. The influence of structural characteristics on adherence to evidence-based quality indicators was low.

Haemorrhagic Transformation after Ischaemic Stroke in Patients Taking Non-vitamin K Antagonist Oral Anticoagulants

Background and Purpose

To evaluate the frequency and outcome of haemorrhagic transformation (HT) after ischaemic stroke in patients treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Methods

Patients with stroke on treatment with a NOAC were prospectively enrolled in this multicentre observational study between February 2012 and 2015. Brain imaging at admission and follow-up imaging until day 7 were reviewed for HT. Functional outcome was assessed by the modified Rankin scale (mRS) before the index event, at discharge, and at 3-months.

Results

231 patients without recanalisation therapy (no-RT), and 32 patients with RT were eligible for analysis. Any HT was present at admission in 9/231 no-RT patients (3.9%, 95% CI 2.0 to 7.3) and in none of the patients with RT. In patients with follow-up imaging (no-RT, n=129, and RT, n=32), HT was present in 14.0% (no-RT; 95% CI, 8.9 to 21.1), and 40.6% (RT, 95% CI, 25.5 to 57.8), respectively. After adjustment for stroke severity, this difference between the no-RT and RT groups became non-significant. Symptomatic ICH was observed in 1 patient per group. HT was not associated with unfavourable outcome (mRS 3-6) at 3-months in multivariable analysis. Resumption of OAC after stroke was delayed in patients with HT compared to those without (15 d [IQR, 5–26] vs. 1 d [0–4], P<0.001).

Conclusions

The frequency and severity of HT after stroke on NOAC appears similar to previous reports for vitamin K antagonists and no anticoagulation. Whether asymptomatic HT should delay resumption of preventive anticoagulation requires further investigation.

Elevated hemoglobin A1c Is Associated with Carotid Plaque Vulnerability: Novel Findings from Magnetic Resonance Imaging Study in Hypertensive Stroke Patients

The association between hemoglobin A1c (HbA1c) level and carotid plaque vulnerability has been rarely studied by magnetic resonance imaging (MRI). The present study of MRI-identified carotid atherosclerotic lesions in hypertensive patients with acute stroke therefore sought to determine the associations between HbA1c level and plaque morphological and compositional characteristics and acute cerebral infarction (ACI) severity. Eighty hypertensive patients with acute stroke were enrolled; stratified into high (≥6.5%) and low (<6.5%) HbA1c groups; and underwent carotid and brain MRI to assess carotid plaque features and ACI volume in the region supplied by the internal carotid artery (ICA) in the symptomatic side. Plaque burden [percent wall volume (PWV), max wall thickness (max-WT)] and lipid-rich necrotic core (LRNC) were larger in the high as compared to the low HbA1c group. High HbA1c was an independent risk factor for the presence of plaque (odds ratio [OR] = 3.71) and LRNC plaque (OR = 7.08). HbA1c independently correlated with ACI severity among patients with ICA region cerebral infarction and carotid plaque. Our study suggested that an elevated HbA1c may have an adverse effect on carotid plaque vulnerability especially those with larger LRNC volumes in hypertensive stroke patients, which might exacerbate the severity of ACIs.

Transcranial Magnetic Stimulation and Diffusion Tensor Tractography for Evaluating Ambulation after Stroke

BACKGROUND AND PURPOSE

We aimed to investigate the usefulness of combining transcranial magnetic stimulation (TMS) and diffusion tensor tractography (DTT) to evaluate corticospinal tract (CST) integrity and subsequently predict ambulatory function after middle cerebral artery (MCA) stroke.

METHODS

Forty-three patients with first MCA stroke underwent TMS and DTT to evaluate CST integrity. Patients were classified into four groups according to the presence of motor-evoked potentials (MEPs) obtained from the tibialis anterior muscle and CST integrity. Motor impairment and functional status were assessed using the Fugl-Meyer Assessment, Functional Ambulation Category, and Korean modified Barthel Index, both at the time of admission and after 4 weeks of rehabilitation.

RESULTS

Patients with the presence of both measurable MEPs and a preserved CST showed better motor recovery and ambulatory function than other groups at the 4-week follow-up. Intact CSTs were not visualized in patients without detectable MEPs. Among the patients displaying MEPs, those with preserved CSTs showed better recovery of paretic lower extremities.

CONCLUSIONS

Combined assessment using TMS and DTT to evaluate CST integrity confers advantages in predicting motor and ambulation recovery in patients with MCA stroke.

Predictors of clinical outcome in patients with acute perforating artery infarction

BACKGROUND AND PURPOSE

We aimed to determine the predictive factors for super-acute perforating artery infarctions (PAI) involving lenticulostriate arteries infarctions (LSAI), anterior pontine arteries infarctions (APAI) and thalamic arteries infarctions (TAI). Whether intravenous thrombolysis (iv-tPA) therapy would influence the clinical outcome was also studied.

METHODS

We analyzed 84 consecutive patients within 12h of stroke symptom onset from January 2008 to June 2015. All patients had an imaging-proven acute infarction in the perforating territory of LSA (n=53), TA (n=21) and APA (n=10). Favorable clinical outcome was defined as modified Rankin Scale ≤1 at 90days. Patients were divided into groups according to clinical outcome, lesion location and thrombolysis therapy. Baseline demographic data, past medical history, National Institutes of Health Stroke Scale (NIHSS) score and infarction volume were compared between groups.

RESULTS

Eighty-four patients were recruited (median age: 61y; 67.9% male). All patients with TAI (n=21), 34/53 (64.2%) patients with LSAI and 4/10 (40%) patients with APAI achieved favorable clinical outcome (mRS≤1). Ninety-day clinical outcome was associated with age, previous stroke, baseline NIHSS, infarct location, infarct volume. Intravenous thrombolysis improved 24h NIHSS, but was not significantly associated with favorable outcome at 90days. In multivariate analysis, only previous stroke/TIA (OR 0.09, 95%CI 0.01-0.68, p=0.020) and infarct volume (OR 0.64, 95%CI 0.43-0.96, p=0.032) were independently associated with the outcome of acute PAI at 90days.

CONCLUSIONS

Previous stroke/TIA, infarct location and infarct volume were independently associated with the short-term clinical outcome of acute PAI.

Younger Stroke Patients With Large Pretreatment Diffusion-Weighted Imaging Lesions May Benefit From Endovascular Treatment

BACKGROUND AND PURPOSE

Lesion volume on diffusion-weighted magnetic resonance imaging (DWI) before acute stroke therapy is a predictor of outcome. Therefore, patients with large volumes are often excluded from therapy. The aim of this study was to analyze the impact of endovascular treatment in patients with large DWI lesion volumes (>70 mL).

METHODS

Three hundred seventy-two patients with middle cerebral or internal carotid artery occlusions examined with magnetic resonance imaging before treatment since 2004 were included. Baseline data and 3 months outcome were recorded prospectively. DWI lesion volumes were measured semiautomatically.

RESULTS

One hundred five patients had lesions >70 mL. Overall, the volume of DWI lesions was an independent predictor of unfavorable outcome, survival, and symptomatic intracerebral hemorrhage (P<0.001 each). In patients with DWI lesions >70 mL, 11 of 31 (35.5%) reached favorable outcome (modified Rankin scale score, 0-2) after thrombolysis in cerebral infarction 2b-3 reperfusion in contrast to 3 of 35 (8.6%) after thrombolysis in cerebral infarction 0-2a reperfusion (P=0.014). Reperfusion success, patient age, and DWI lesion volume were independent predictors of outcome in patients with DWI lesions >70 mL. Thirteen of 66 (19.7%) patients with lesions >70 mL had symptomatic intracerebral hemorrhage with a trend for reduced risk with avoidance of thrombolytic agents.

CONCLUSIONS

There was a growing risk for poor outcome and symptomatic intracerebral hemorrhage with increasing pretreatment DWI lesion volumes. Nevertheless, favorable outcome was achieved in every third patient with DWI lesions >70 mL after successful endovascular reperfusion, whereas after poor or failed reperfusion, outcome was favorable in only every 12th patient. Therefore, endovascular treatment might be considered in patients with large DWI lesions, especially in younger patients.

The predictive value of the Boston Acute Stroke Imaging Scale (BASIS) in acute ischemic stroke patients among Chinese population

Objective

Evaluate the predictive value of Boston Acute Stroke Imaging Scale (BASIS) in acute ischemic stroke in Chinese population.

Methods

This was a retrospective study. 566 patients of acute ischemic stroke were classified as having a major stroke or minor stroke based on BASIS. We compared short-term outcome (death, occurrence of complications, admission to intensive care unit [ICU] or neurological intensive care unit [NICU]), long-term outcome (death, recurrence of stroke, myocardial infarction, modified Rankin scale) and economic index including in-hospital cost and length of hospitalization. Continuous variables were compared by using the Student t test or Kruskal-Wallis test. Categorical variables were tested with the Chisquare test. Cox regression analysis was applied to identify whether BASIS was the independent predictive variable of death.

Results

During hospitalization, 9 patients (4.6%) died in major stroke group while no patients died in minor stroke group (p<0.001), 12 patients in the major stroke group and 5 patients in minor stroke group were admitted to ICU/NICU (p = 0.001). There were more complications (cerebral hernia, pneumonia, urinary tract infection) in major stroke group than minor stroke group (p<0.05). Meanwhile, the average cost of hospitalization in major stroke group was 3,100 US$ and 1,740 US$ in minor stroke group (p<0.001); the average length of stay in major and minor stroke group was 21.3 days and 17.3 days respectively (p<0.001). Results of the follow-up showed that 52 patients (26.7%) died in major stroke group while 56 patients (15.1%) died in minor stroke group (P<0.001). 62.2% of the patients in major stroke group and 80.4% of the patients in minor stroke group were able to live independently (P = 0.002). The survival analysis showed that patients with major stroke had 80% higher of risk of death than patients with minor stroke even after adjusting traditional atherosclerotic factors and NIHSS at baseline (HR = 1.8, 95% CI: 1.1–3.1).

Conclusion

BASIS can predict in-hospital mortality, occurrence of complication, length of stay and hospitalization cost of the acute ischemic stroke patients and can also estimate the long term outcome (death and the dependency). BASIS could and should be used as a dichotomous stroke classification system in the daily practice.