Treatment of Acute Ischemic Stroke: The Last 30 Years of Trials and Tribulations

The landscape of acute ischemic stroke management has undergone a substantial transformation over the past 3 decades, mirroring our enhanced comprehension of the pathology and progress in diagnostic techniques, therapeutic interventions, and preventive measures. The 1990s marked a pivotal moment in stroke care with the integration of intravenous thrombolytics. However, the most significant paradigm shift in recent years has undoubtedly been the advent of endovascular thrombectomy. This article endeavors to deliver an exhaustive analysis of this revolutionary progression.

Effect of chronic antiplatelet therapy on clinical outcomes of endovascular thrombectomy for treatment of acute ischemic stroke

OBJECTIVE

The objective of this study was to investigate the prognostic significance of chronic antiplatelet therapy (APT) usage in acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). Long-term APT may enhance recanalization but may also predispose patients to an increased risk of hemorrhagic transformation.

METHODS

Weighted hospitalizations for anterior-circulation AIS treated with EVT were identified in a large United States claims-based registry. Baseline clinical characteristics and outcomes were compared between patients with and without chronic APT usage prior to admission. Multivariable logistic regression analysis was performed to assess adjusted associations between APT and study endpoints.

RESULTS

This analysis identified 36,560 patients, of whom 8170 (22.3%) were on a chronic APT regimen prior to admission. These patients were older and demonstrated a higher burden of comorbid disease, but had similar stroke severity on presentation in comparison with those not on APT. On unadjusted analysis, patients with prior APT demonstrated higher rates of favorable outcomes (24.3% vs 21.5%, p < 0.001), lower rates of mortality (7.0% vs 10.1%, p < 0.001), and lower rates of any intracranial hemorrhage (ICH; 20.3% vs 24.2%, p < 0.001), but no difference in rates of symptomatic ICH (sICH). Following multivariable adjustment for baseline clinical characteristics including age, acute stroke severity, and comorbidity burden, prior APT was associated with favorable outcome (adjusted odds ratio [aOR] 1.21, 95% CI 1.17-1.24, p < 0.001) and a lower likelihood of mortality (aOR 0.73, 95% CI 0.70-0.77, p < 0.001), without an increased likelihood of ICH (any ICH aOR 0.84, 95% CI 0.81-0.87, p < 0.001; sICH aOR 0.92, 95% CI 0.82-1.03, p = 0.131).

CONCLUSIONS

Retrospective evaluation of patients with AIS treated with EVT using registry-based data demonstrated an association of prior APT usage with favorable outcomes, without an increased risk of hemorrhagic transformation.

Intravenous thrombolysis for treatment of pediatric acute ischemic stroke: Analysis of 20 years of population-level data in the United States

BACKGROUND AND AIMS

Although intravenous thrombolysis (IVT) represents standard-of-care treatment for acute ischemic stroke (AIS) in eligible adult patients, definitive evidence-based guidelines and randomized clinical trial data evaluating its safety and efficacy in the pediatric population remain absent from the literature. We aimed to evaluate the utilization and outcomes of IVT for the treatment of pediatric AIS using a large national registry.

METHODS

Weighted hospitalizations for pediatric (<18 years of age) AIS patients were identified in the National Inpatient Sample during the period of 2001 to 2019. Complex sample statistical methods were performed to assess unadjusted and adjusted outcomes in patients treated with IVT or other medical management.

RESULTS

Among 13,901 pediatric AIS patients, 270 (1.9%) were treated with IVT monotherapy (median age 12.8 years). IVT-treated patients developed any intracranial hemorrhage (ICH) at a rate of 5.6% (n = 15), and 71.9% (n = 194) experienced favorable functional outcomes at discharge (to home or to acute rehabilitation). Following propensity-score adjustment for age, acute stroke severity, infarct location, and etiological/comorbid conditions, IVT was not associated with an increased risk of any ICH (5.6% vs 5.4%, p = 0.931; adjusted odds ratio (aOR) = 1.01, 95% confidence interval (CI) = 0.48-2.14, p = 0.971), nor with favorable functional outcome (71.9% vs 74.5%, p = 0.489; aOR = 0.88, 95% CI = 0.60-1.29, p = 0.511) in comparison with other medical therapy.

CONCLUSIONS

Twenty years of population-level data in the United States demonstrate that pediatric AIS patients treated with IVT experienced high rates of favorable outcomes without an increased risk of hemorrhagic transformation.

Association of Elevated Body Mass Index with Functional Outcome and Mortality following Acute Ischemic Stroke: The Obesity Paradox Revisited

BACKGROUND

Previous literature has identified a survival advantage in acute ischemic stroke (AIS) patients with elevated body mass indices (BMIs), a phenomenon termed the "obesity paradox."

OBJECTIVE

The aim of this study was to evaluate the independent association between obesity and clinical outcomes following AIS.

METHODS

Weighted discharge data from the National Inpatient Sample were queried to identify AIS patients from 2015 to 2018. Multivariable logistic regression and Cox proportional hazards modeling were performed to evaluate associations between obesity (BMI ≥ 30) and clinical endpoints following adjustment for acute stroke severity and comorbidity burden.

RESULTS

Among 1,687,805 AIS patients, 216,775 (12.8%) were obese. Compared to nonobese individuals, these patients were younger (64 vs. 72 mean years), had lower baseline NIHSS scores (6.9 vs. 7.9 mean score), and a higher comorbidity burden. Multivariable analysis demonstrated independent associations between obesity and lower likelihood of mortality (adjusted odds ratio [aOR] 0.76, 95% confidence interval [CI]: 0.71, 0.82, p < 0.001; hazard ratio 0.84, 95% CI: 0.73, 0.97, p = 0.015), intracranial hemorrhage (aOR 0.87, 95% CI: 0.82, 0.93, p < 0.001), and routine discharge to home (aOR 0.97, 95% CI: 0.95, 0.99; p = 0.015). Mortality rates between obese and nonobese patients were significantly lower across stroke severity thresholds, but this difference was attenuated among high severity (NIHSS > 20) strokes (21.6% vs. 23.2%, p = 0.358). Further stratification of the cohort into BMI categories demonstrated a "U-shaped" association with mortality (underweight aOR 1.58, 95% CI: 1.39, 1.79; p < 0.001, overweight aOR 0.64, 95% CI: 0.42, 0.99; p = 0.046, obese aOR 0.77, 95% CI: 0.71, 0.83; p < 0.001, severely obese aOR 1.18, 95% CI: 0.74, 1.87; p = 0.485). Sub-cohort assessment of thrombectomy-treated patients demonstrated an independent association of obesity (BMI 30-40) with lower mortality (aOR 0.79, 95% CI: 0.65, 0.96; p = 0.015), but not with routine discharge.

CONCLUSION

This cross-sectional analysis demonstrates a lower likelihood of discharge to home as well as in-hospital mortality in obese patients following AIS, suggestive of a protective effect of obesity against mortality but not against all poststroke neurological deficits in the short term which would necessitate placement in acute rehabilitation and long-term care facilities.

Obstructive sleep apnea confers lower mortality risk in acute ischemic stroke patients treated with endovascular thrombectomy: National Inpatient Sample analysis 2010-2018

BackgroundObstructive sleep apnea (OSA) portends increased morbidity and mortality following acute ischemic stroke (AIS). Evaluation of OSA in the setting of AIS treated with endovascular mechanical thrombectomy (MT) has not yet been evaluated in the literature.

METHODS

The National Inpatient Sample from 2010 to 2018 was utilized to identify adult AIS patients treated with MT. Those with and without OSA were compared for clinical characteristics, complications, and discharge disposition. Multivariable logistic regression analysis and propensity score adjustment (PA) were employed to evaluate independent associations between OSA and clinical outcome.

RESULTS

Among 101 093 AIS patients treated with MT, 6412 (6%) had OSA. Those without OSA were older (68.5 vs 65.6 years old, p<0.001), female (50.5% vs 33.5%, p<0.001), and non-caucasian (29.7% vs 23.7%, p<0.001). The OSA group had significantly higher rates of obesity (41.4% vs 10.5%, p<0.001), atrial fibrillation (47.1% vs 42.2%, p=0.001), hypertension (87.4% vs 78.5%, p<0.001), and diabetes mellitus (41.2% vs 26.9%, p<0.001). OSA patients treated with MT demonstrated lower rates of intracranial hemorrhage (19.1% vs 21.8%, p=0.017), treatment of hydrocephalus (0.3% vs 1.1%, p=0.009), and in-hospital mortality (9.7% vs 13.5%, p<0.001). OSA was independently associated with lower rate of in-hospital mortality (aOR 0.76, 95% CI 0.69 to 0.83; p<0.001), intracranial hemorrhage (aOR 0.88, 95% CI 0.83 to 0.95; p<0.001), and hydrocephalus (aOR 0.51, 95% CI 0.37 to 0.71; p<0.001). Results were confirmed by PA.

CONCLUSIONS

Our findings suggest that MT is a viable and safe treatment option for AIS patients with OSA.

Socioecological differences in factors associated with inconsistent condom use with female sex workers and casual partners: an observational study of heterosexual men attending an anonymous HIV testing clinic in Singapore

Sexual practices among heterosexual men may differ between female sex workers (FSWs) and casual partners. We surveyed 203 heterosexual men and investigated the attributes associated with inconsistent condom use among them. Lower educational attainment was positively associated with inconsistent condom use with FSWs (adjusted prevalence ratio (aPR) 2.63; P = 0.018) and casual partners (aPR 1.55; P = 0.022), whereas early age of sexual debut (aPR 3.00; P = 0.012) and alcohol use during sex (aPR 7.95; P < 0.001) were positively associated with inconsistent condom use with FSWs. Socioecological factors may explain such differences.

Abstract 75: Predictors of Poor Outcome After Intracerebral Hemorrhage: Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) Study

Introduction: Intracerebral hemorrhage (ICH) is the most severe subtype of stroke with a high mortality rate and majority of survivors suffering significant disability. The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study prospectively recruited 1000 white, 1000 black and 1000 Hispanic spontaneous ICH cases. Herein, we report the main results of the predictors of 3 month outcome after ICH.

Hypothesis: We hypothesized that ICH Score variables of age, ICH volume, ICH location, presence of intraventricular hemorrhage (IVH), and presenting Glasgow Coma Scale would predict long-term disability in addition to prior validation of mortality.

Methods: Between 2010-2015, cases were prospectively recruited with uniform phenotype definitions, centralized neuroimaging review and with telephone follow-up at 3 months. Apolipoprotein E genotyping was performed centrally. Individual characteristics were screened for association under a logistic regression model, 90-day mRS ≥ 4 versus 0-3, and those meeting P<0.2 were entered into multivariate model building where the final model was determined by minimum AIC score. Analyses were repeated removing subjects with withdrawal of care.

Results: The Table presents the prevalence/average of each variable entering the final multivariate model for association with poor (mRS 4-6) compared to good (mRS 0-3) outcome at 3 months. When analyses were repeated excluding withdrawal of care, overall Graeb (IVH) score fell out of the model (with presence of IVH replacing it) but the remaining variables were retained and in the same direction of effect. C-statistic for the multivariate model = 0.884 compared to 0.763 for ICH score alone (p=1.7E-22).

Conclusion: ICH score elements were validated as predictive of 3 month outcome. Novel baseline characteristics such as white matter hyperintensity as well as subsequent clinical events that may affect outcomes were identified. Location specific results to be presented.

Racial-ethnic disparities in acute blood pressure after intracerebral hemorrhage

OBJECTIVE

To assess race-ethnic differences in acute blood pressure (BP) following intracerebral hemorrhage (ICH) and the contribution to disparities in ICH outcome.

METHODS

BPs in the field (emergency medical services [EMS]), emergency department (ED), and at 24 hours were compared and adjusted for group differences between non-Hispanic black (black), non-Hispanic white (white), and Hispanic participants in the Ethnic Racial Variations of Intracerebral Hemorrhage case-control study. Outcome was obtained by modified Rankin Scale (mRS) score at 3 months. We analyzed race-ethnic differences in good outcome (mRS ≤ 2) and mortality after adjusting for baseline differences and included BP recordings in this model.

RESULTS

Of 2,069 ICH cases enrolled, 30% were white, 37% black, and 33% Hispanic. Black and Hispanic patients had higher EMS and ED systolic and diastolic BPs compared with white patients (p = 0.0001). Although attenuated, at 24 hours after admission, black patients had higher systolic and diastolic BPs. After adjusting for baseline differences, significant race/ethnic differences persisted for EMS systolic, ED systolic and diastolic, and 24-hours diastolic BP. Only ED systolic and diastolic BP was associated with poor functional outcome, and no BP predicted mortality. We found no race-ethnic differences in 3-month functional outcome or mortality after adjusting for group differences, including acute BPs.

CONCLUSIONS

Although black and Hispanic patients had higher BPs than white patients at presentation, we did not find race-ethnic disparities in 3-month functional outcome or mortality. ED systolic and diastolic BP was associated with poor functional outcome, but not mortality, in this race-ethnically diverse population.

Critical Care Management of Increased Intracranial Pressure

Increased intracranial pressure (ICP) is a pathologic state common to a variety of serious neurologic conditions, all of which are characterized by the addition of volume to the intracranial vault. Hence all ICP therapies are directed toward reducing intracranial volume. Elevated ICP can lead to brain damage or death by two principle mechanisms: (1) global hypoxic-ischemic injury, which results from reduction of cerebral perfusion pressure (CPP) and cerebral blood flow, and (2) mechanical compression, displacement, and herniation of brain tissue, which results from mass effect associated with compartmentalized ICP gradients. In unmonitored patients with acute neurologic deterioration, head elevation (30 degrees), hyperventilation (pCO2 26-30 mmHg), and mannitol (1.0-1.5 g/kg) can lower ICP within minutes. Fluid-coupled ventricular catheters and intraparenchymal pressure transducers are the most accurate and reliable devices for measuring ICP in the intensive care unit (ICU) setting. In a monitored patient, treatment of critical ICP elevation (>20 mmHg) should proceed in the following steps: (1) consideration of repeat computed tomography (CT) scanning or consideration of definitive neurosurgical intervention, (2) intravenous sedation to attain a quiet, motionless state, (3) optimization of CPP to levels between 70 and 110 mmHg, (4) osmotherapy with mannitol or hypertonic saline, (5) hyperventilation (pCO2 26-30 mmHg), (6) high-dose pentobarbital therapy, and (7) systemic cooling to attain moderate hypothermia (32-33°C). Placement of an ICP monitor and use of a stepwise treatment algorithm are both essential for managing ICP effectively in the ICU setting.

UV-Enhanced Sacrificial Layer Stabilised Graphene Oxide Hollow Fibre Membranes for Nanofiltration

Graphene oxide (GO) membranes have demonstrated great potential in gas separation and liquid filtration. For upscale applications, GO membranes in a hollow fibre geometry are of particular interest due to the high-efficiency and easy-assembly features at module level. However, GO membranes were found unstable in dry state on ceramic hollow fibre substrates, mainly due to the drying-related shrinkage, which has limited the applications and post-treatments of GO membranes. We demonstrate here that GO hollow fibre membranes can be stabilised by using a porous poly(methyl methacrylate) (PMMA) sacrificial layer, which creates a space between the hollow fibre substrate and the GO membrane thus allowing stress-free shrinkage. Defect-free GO hollow fibre membrane was successfully determined and the membrane was stable in a long term (1200 hours) gas-tight stability test. Post-treatment of the GO membranes with UV light was also successfully accomplished in air, which induced the creation of controlled microstructural defects in the membrane and increased the roughness factor of the membrane surface. The permeability of the UV-treated GO membranes was greatly enhanced from 0.07 to 2.8 L m⁻² h⁻¹ bar⁻¹ for water, and 0.14 to 7.5 L m⁻² h⁻¹ bar⁻¹ for acetone, with an unchanged low molecular weight cut off (~250 Da).

Abstract W MP36: IV tPA Utilization and Outcomes in Asian Americans

Intro: Studies have shown race/ethnic differences in IV tPA utilization and outcomes after acute ischemic stroke (IS). Most studies in the US have examined differences in Black, White, and Hispanic populations. We aimed to examine tPA utilization and outcomes in Asian Americans.

Methods: We used administrative claims data on all discharges from nonfederal EDs and acute care hospitals in CA, FL, and NY from 2006 through 2011 (CA and NY) or 2012 (FL). We identified patients with a first-recorded hospitalization for IS using a validated algorithim and included discharge diagnosis of ICH or SAH if treated with tPA to capture cases of hemorrhagic transformation of an infarct. IV tPA was identified by ICD-9-CM procedure code 99.10. We used descriptive statistics to compare rates of IV tPA among different races. We used multiple logistic regression to assess the relationship between race and IV tPA use while adjusting for other demographic characteristics, vascular risk factors, and Elixhauser comorbid conditions. We assessed rates of ICH/SAH and inhospital mortality by race in patients treated with tPA.

Results: Among 587,560 IS patients, 63.9% were White, 14.1% Black, 12.5% Hispanic, 4.5% Asian, 0.2% American Indian, and 2.8% other; 2.0% had missing data on race. Mean age was 72 years and 52% were women. Overall 4.8% received IV tPA. tPA use was 5.1% in Whites, 3.9% in Blacks, 3.9% in Hispanics, and 4.7% in Asians. After adjusting for age, gender, insurance status, and comorbidities, tPA use was less likely in non-White patients: Black OR 0.78 (95% CI 0.75-0.81), Hispanic OR 0.78 (95% CI 0.75-0.81), and Asian OR 0.94 (95% CI 0.88-0.995). ICH/SAH after tPA occurred in 16.9% of Asians compared with 11.3% of Whites, 12.2% of Blacks, and 13.6% of Hispanics. In multivariable analysis, Asian race was independently associated with ICH/SAH (OR 1.51; 95% CI 1.29-1.77). In-hospital mortality was also significantly higher in Asians (14.7%) compared to whites (12.6%); OR 1.19 (1.00-1.4).

Conclusion: Asian patients less often receive tPA for IS. They also have higher rates of hemorrhage and in-hospital death after tPA. These findings are limited by lack of data on stroke severity, mechanisms, and treatment times. Further studies including these patient characteristics are warranted.

Risk factor management for stroke prevention

PURPOSE OF REVIEW

This review focuses on the recommendations for management of hypertension, dyslipidemia, diabetes mellitus, diet, physical activity, and lifestyle choices commonly encountered in neurologic practice. Specific studies, including those relevant to lipid targets, blood pressure targets, and adherence to medications after stroke, are reviewed.

RECENT FINDINGS

In addition to traditional risk factors such as hypertension, dyslipidemia, and diabetes mellitus, this review discusses sleep apnea, diet, physical activity, and other novel risk factors that are potentially modifiable. Recent studies confirm that pharmacologic strategies to achieve aggressive targets for lipid and blood pressure lowering have significant impact on recurrent stroke risk.

SUMMARY

Optimal secondary prevention strategies can prevent as much as 80% of all recurrent strokes.

Abstract 179: Racial-ethnic Blood Pressure Differences in Acute Intracerebral Hemorrhage

Background: Intracerebral hemorrhage (ICH) incidence and hypertension prevalence vary among racial-ethnic groups. Elevated blood pressure (BP) is common following ICH, but there are few racial/ethnic comparisons of acute BP. This study assessed the BP response to acute ICH in a multi-ethnic population.

Methods: We examined BP in the field (EMS), emergency department (ED) and at 24 hours after ICH in subjects enrolled in the Ethnic Racial Variations of Intracerebral Hemorrhage (ERICH) study. ERICH is a multi-center prospective case-control study of ICH in non-Hispanic whites (whites), non-Hispanic blacks (blacks) and Hispanics. Baseline characteristics and BP recordings by EMS, in the ED and at 24 hours were analyzed for group differences.

Results: Of 1052 subjects enrolled, BP recordings were available by EMS in 370, ED in 1041 and at 24 hours in 1014 cases of which 24% were white, 42% black and 34% Hispanic. Whites were significantly older 68± 14 years than blacks (58±13 years) and Hispanics (59± 15 years) (p≤0.0001) and had more lobar hemorrhages (39% vs. 23% blacks and 26% Hispanics; p≤0.0001). Baseline differences included larger hematoma volumes, in whites, and more frequent hypertension history and substance use, including cocaine use and smoking, in blacks. Blacks and Hispanics had significantly higher EMS (p=0.0001) and ED (p=0.0001) systolic BPs compared to whites (blacks: 198± 39, 195± 37; Hispanics: 191± 41, 191± 39; whites: 173± 37, 176± 37 mmHg). At 24 hours blacks had a higher systolic BP (144± 25 mmHg; p=0.0014) than Hispanics and whites (139± 21 and 138± 22 mmHg). These differences remained significant after adjustment for baseline group differences, including lobar and deep location. In multivariate analysis, low GCS and being black were associated with a systolic BP> 140mmHg at 24h. Blacks were more likely to receive BP treatment in the ER when compared to whites and Hispanics (76% vs. 52% and 68%).

Conclusion: We found significant differences in the acute BP response to ICH, with blacks and Hispanics having a higher systolic BP at acute presentation. At 24 hours systolic BP remained elevated in blacks. These findings contribute to our understanding of racial-ethnic differences in BP and identify groups at risk for continued BP elevation.

The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study protocol

BACKGROUND AND PURPOSE

Epidemiological studies of intracerebral hemorrhage (ICH) have consistently demonstrated variation in incidence, location, age at presentation, and outcomes among non-Hispanic white, black, and Hispanic populations. We report here the design and methods for this large, prospective, multi-center case-control study of ICH.

METHODS

The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study is a multi-center, prospective case-control study of ICH. Cases are identified by hot-pursuit and enrolled using standard phenotype and risk factor information and include neuroimaging and blood sample collection. Controls are centrally identified by random digit dialing to match cases by age (±5 years), race, ethnicity, sex, and metropolitan region.

RESULTS

As of March 22, 2013, 1655 cases of ICH had been recruited into the study, which is 101.5% of the target for that date, and 851 controls had been recruited, which is 67.2% of the target for that date (1267 controls) for a total of 2506 subjects, which is 86.5% of the target for that date (2897 subjects). Of the 1655 cases enrolled, 1640 cases had the case interview entered into the database, of which 628 (38%) were non-Hispanic black, 458 (28%) were non-Hispanic white, and 554 (34%) were Hispanic. Of the 1197 cases with imaging submitted, 876 (73.2%) had a 24 hour follow-up CT available. In addition to CT imaging, 607 cases have had MRI evaluation.

CONCLUSIONS

The ERICH study is a large, case-control study of ICH with particular emphasis on recruitment of minority populations for the identification of genetic and epidemiological risk factors for ICH and outcomes after ICH.

Intravascular ultrasound of symptomatic intracranial stenosis demonstrates atherosclerotic plaque with intraplaque hemorrhage: a case report

BACKGROUND

Intracranial artery stenosis is assumed to represent atherosclerotic plaque. Catheter cerebral arteriography shows that intracranial stenosis may progress, regress, or remain unchanged. It is counterintuitive that atherosclerotic plaque should spontaneously regress, raising questions about the composition of intracranial stenoses. Little is known about this disease entity in vivo. We provide the first demonstration of in vivo atherosclerotic plaque with intraplaque hemorrhage using intravascular ultrasound (IVUS).

CASE DESCRIPTION

A 35-year-old man with multiple vascular risk factors presented with recurrent stroke failing medical therapy. Imaging demonstrated left internal carotid artery occlusion, severe intracranial right internal carotid artery stenosis, and cerebral perfusion failure. Cerebral arteriography with IVUS confirmed 85% stenosis of the petrous right carotid artery due to atherosclerotic plaque with intraplaque hemorrhage. Intracranial stent-supported angioplasty was performed with IRB approval. The patient recovered without complication.

CONCLUSIONS

This case supports the premise that symptomatic intracranial stenosis can be caused by atherosclerotic plaque complicated by intraplaque hemorrhage similar to coronary artery plaque. IVUS provides additional characteristics that define intracranial atherosclerosis and high-risk features. To our knowledge, this is the first report of stroke due to unstable atherosclerotic plaque with intraplaque hemorrhage in vivo.

A Computerized Algorithm for Etiologic Classification of Ischemic Stroke

Background and Purpose— The SSS-TOAST is an evidence-based classification algorithm for acute ischemic stroke designed to determine the most likely etiology in the presence of multiple competing mechanisms. In this article, we present an automated version of the SSS-TOAST, the Causative Classification System (CCS), to facilitate its utility in multicenter settings.

Methods— The CCS is a web-based system that consists of questionnaire-style classification scheme for ischemic stroke (http://ccs.martinos.org). Data entry is provided via checkboxes indicating results of clinical and diagnostic evaluations. The automated algorithm reports the stroke subtype and a description of the classification rationale. We evaluated the reliability of the system via assessment of 50 consecutive patients with ischemic stroke by 5 neurologists from 4 academic stroke centers.

Results— The kappa value for inter-examiner agreement was 0.86 (95% CI, 0.81 to 0.91) for the 5-item CCS (large artery atherosclerosis, cardio-aortic embolism, small artery occlusion, other causes, and undetermined causes), 0.85 (95% CI, 0.80 to 0.89) with the undetermined group broken into cryptogenic embolism, other cryptogenic, incomplete evaluation, and unclassified groups (8-item CCS), and 0.80 (95% CI, 0.76 to 0.83) for a 16-item breakdown in which diagnoses were stratified by the level of confidence. The intra-examiner reliability was 0.90 (0.75–1.00) for 5-item, 0.87 (0.73–1.00) for 8-item, and 0.86 (0.75–0.97) for 16-item CCS subtypes.

Conclusions— The web-based CCS allows rapid analysis of patient data with excellent intra- and inter-examiner reliability, suggesting a potential utility in improving the fidelity of stroke classification in multicenter trials or research databases in which accurate subtyping is critical.

Inter-individual variability in the capacity for motor recovery after ischemic stroke

BACKGROUND

Motor recovery after stroke is predicted only moderately by clinical variables, implying that there is still a substantial amount of unexplained, biologically meaningful variability in recovery. Regression diagnostics can indicate whether this is associated simply with Gaussian error or instead with multiple subpopulations that vary in their relationships to the clinical variables.

OBJECTIVE

To perform regression diagnostics on a linear model for recovery versus clinical predictors.

METHODS

Forty-one patients with ischemic stroke were studied. Impairment was assessed using the upper extremity Fugl-Meyer Motor Score. Motor recovery was defined as the change in the upper extremity Fugl-Meyer Motor Score from 24 to 72 hours after stroke to 3 or 6 months later. The clinical predictors in the model were age, gender, infarct location (subcortical vs cortical), diffusion weighted imaging infarct volume, time to reassessment, and acute upper extremity Fugl-Meyer Motor Score. Regression diagnostics included a Kolmogorov-Smirnov test for Gaussian errors and a test for outliers using Studentized deleted residuals.

RESULTS

In the random sample, clinical variables explained only 47% of the variance in recovery. Among the patients with the most severe initial impairment, there was a set of regression outliers who recovered very poorly. With the outliers removed, explained variance in recovery increased to 89%, and recovery was well approximated by a proportional relationship with initial impairment (recovery congruent with 0.70 x initial impairment).

CONCLUSIONS

Clinical variables only moderately predict motor recovery. Regression diagnostics demonstrated the existence of a subpopulation of outliers with severe initial impairment who show little recovery. When these outliers were removed, clinical variables were good predictors of recovery among the remaining patients, showing a tight proportional relationship to initial impairment.

Impact of Abnormal Diffusion-Weighted Imaging Results on Short-term Outcome Following Transient Ischemic Attack

OBJECTIVE

To characterize short-term prognoses among patients with transient ischemic attack (TIA) and normal diffusion-weighted imaging (DWI) results, TIA patients with abnormal DWI results (transient symptoms associated with infarction [TSI]), and patients with completed ischemic stroke (IS).

DESIGN

Retrospective study.

SETTING

University hospital.

PATIENTS

We reviewed patient medical records between January 2003 and December 2004 with International Classification of Diseases, Ninth Revision codes for TIA at admission, resolution of neurological symptoms within 24 hours, magnetic resonance imaging within 48 hours, and a discharge diagnosis of TIA or IS. A random sample of 50 IS patients was selected from all IS admissions and discharges by International Classification of Diseases, Ninth Revision codes. Demographic, clinical, radiographic, and in-hospital outcome data were recorded. Three diagnostic categories were created: TIA with normal DWI results, TSI, and IS. Multivariate logistic regression was used to estimate the association between diagnostic category and rate of in-hospital stroke or recurrent TIA among the 3 groups.

RESULTS

We identified 146 classic TIA (25% with TSI) and 50 IS cases. There were 4 recurrent TIAs and 6 strokes among patients with TSI (27.0%); 3 recurrent TIAs and no strokes among patients with normal DWI results (2.8%); and 1 recurrent stroke and no TIAs among IS patients (2.0%). Transient symptoms associated with infarction was independently associated with in-hospital recurrent TIA or stroke (adjusted odds ratio, 11.2; P < .01).

CONCLUSIONS

Transient symptoms associated with infarction is associated with a greater rate of early recurrent TIA and stroke than both IS and TIA with normal DWI results. These data suggest that TSI may be a separate clinical entity with unique prognostic implications.

Experimental treatments for acute ischaemic stroke

Treatments for acute ischaemic stroke continue to evolve. Experimental approaches to restore cerebral perfusion include techniques to augment recanalising therapies, including combination of antiplatelet agents with intravenous thrombolysis, bridging therapy of combining intravenous with intra-arterial thrombolysis, and trials of new thrombolytic agents. Trials with MRI selection criteria are underway to expand the window of opportunity for thrombolysis. Sonothrombolysis and novel endovascular mechanical devices to retrieve or dissolve acute cerebral occlusions are being tested. Approaches to improve cerebral perfusion with other devices and induced hypertension are also being considered. Although numerous neuroprotective agents have not shown benefit, trials of hypothermia, magnesium, caffeinol, high doses of statins, and albumin are continuing. The findings of these randomised trials are anticipated to allow improved treatment of patients with acute stroke.

Gender differences in self-report of recovery after stroke: the Northern Manhattan Study

We compared subjective responses to simple questions after stroke with interviewer-assessed stroke outcome measures. Among those in the highest functional category, women were more likely to report incomplete recovery and greater need for help than men. Among these women, depressed mood was associated with a response of a need for help despite a good functional recovery. Self-reported responses in stroke outcome assessments require further validation by gender and may need to consider the confounding effects of depression.

Epidemiology of stroke in young adults: race/ethnic differences

Stroke is the third leading cause of death and the leading cause of disability in the United States. Stroke incidence is clearly associated with advancing age. Although younger adults are at lower risk, stroke in this population has a particularly high public health impact because of associated indirect costs, such as longer years of lost productivity.There have been many epidemiological studies addressing race ethnic differences in overall stroke incidence and mortality, but few specifically examining these differences in the young adult population. There is evidence that race ethnic differences may have a greater effect on stroke incidence and mortality in young adults. An understanding of these differences may help better identify high risk populations and focus preventative strategies. Furthermore, analysis of race/ethnic differences in stroke subtypes may help clarify mechanisms of stroke in young adults and potential race-ethnic differences in early stroke risk factors.

Stroke as a complication of congenital heart disease

Patent foramen ovale is a common finding in the general population. It is associated with an increased risk of stroke, but it may not have a significant effect on recurrent stroke risk in medically treated patients. Recently, many questions have arisen with respect to best treatment for preventing recurrent stroke. Some data from a clinical trial of anticoagulation compared with antiplatelet therapy support antiplatelet treatment for secondary prevention. There are not enough data currently to support surgical or percutaneous closure of patent foramen ovale for stroke prevention.

Anticoagulation and platelet antiaggregation therapy in stroke prevention

PURPOSE OF REVIEW

The results of recent large clinical trials have modified treatment plans formerly based on inferred mechanisms of ischemic stroke and hazards of certain forms of therapy.

RECENT FINDINGS

Strong data have emerged to support anticoagulation with warfarin for stroke associated with inferred embolism in a setting of atrial fibrillation. No clear advantage for warfarin over aspirin exists for ischemic stroke in a setting of intracranial atheroma, patent cardiac foramen ovale, or elevated levels of antiphospholipid antibody. Among antiplatelet agents, aspirin and clopidogrel have a similar recurrent stroke risk. Combination therapies with aspirin and warfarin show no additional benefits with regard to stroke prevention and carry higher risks of hemorrhage. Treatment with aspirin combined with specially formulated long-acting dipyridamole carries a lower risk of stroke than aspirin alone and does not increase the risk of hemorrhage significantly. The combination of aspirin and clopidogrel does not reduce the risk of stroke over clopidogrel alone and carries a greater risk of bleeding than clopidogrel alone.

SUMMARY

Choice of antithrombotic therapy depends on the etiology of the stroke. Oral anticoagulation treatment is the preferred choice for inferred cardioembolism in the setting of atrial fibrillation, while the varying rates of hemorrhage with oral anticoagulants continue to favor antiplatelet therapy in other settings of inferred etiology. Combinations of antithrombotic therapy vary in their lowering of stroke rate, and some raise the risk of hemorrhage. Insufficient data exist to determine whether antithrombotic therapy combined with antihypertensives, statins or other agents will further reduce the risk of stroke in synergistic or supplemental fashion, or give no additional benefit.

Intravenous thrombolytic treatment of acute ischemic stroke associated with left atrial myxoma: A case report

There are few data available regarding the safety or efficacy of thrombolysis of acute ischemic stroke secondary to myxoma. We present a patient treated with intravenous recombinant tissue plasminogen activator who developed hemorrhage remote from the location of ischemic stroke. Intra-arterial local thrombolysis may be a preferable alternative because of greater risk of hemorrhage from occult tumor emboli or microaneurysms in these patients.

Dural arteriovenous fistula presents like an ischemic stroke

OBJECTIVE

We report the case of a patient with a dural arteriovenous fistula whose neurobehavioral syndrome was indistinguishable from that of an ischemic stroke.

BACKGROUND

Case studies of dural arteriovenous fistulas primarily describe global cognitive changes like dementia, but detailed neurocognitive evaluations of dural arteriovenous fistula patients are rarely reported.

METHOD

We provide a dural arteriovenous fistula case of a patient who presented with aphasia and other symptoms of stroke. Background history, serial neuropsychological data, and angiographic images are presented.

RESULTS AND CONCLUSIONS

Serial neurocognitive data show the extent to which cognitive deficits are reversed with embolization. The case demonstrates that the mechanisms underlying neurocognitive deficits are specific to the fistula's unique hemodynamic features in addition to the location of the dural arteriovenous fistula.

Hashimoto encephalopathy: syndrome or myth?

BACKGROUND

Hashimoto encephalopathy has been described as a syndrome of encephalopathy and high serum antithyroid antibody concentrations that is responsive to glucocorticoid therapy, but these could be chance associations.

OBJECTIVE

To study a patient with Hashimoto encephalopathy and to review the literature to determine whether Hashimoto encephalopathy is an identifiable syndrome.

DATA SOURCES AND EXTRACTION

We searched the MEDLINE database to June 2002 for "Hashimoto" or "autoimmune thyroiditis" and "encephalopathy" and examined all identified articles and articles referenced therein, including all languages. We included all patients with noninfectious encephalopathy (clouding of consciousness and impaired cognitive function) and high serum antithyroid antibody concentrations. We excluded patients if they did not meet these inclusion criteria or if their symptoms could be explained by another neurologic disorder. We recorded clinical features and the results of imaging, electroencephalographic, thyroid function, and cerebrospinal fluid studies.

DATA SYNTHESIS

We identified 85 patients (69 women and 16 men; mean age, 44 years) with encephalopathy and high serum antithyroid antibody concentrations. Among these patients, 23 (27%) had strokelike signs, 56 (66%) had seizures, 32 (38%) had psychosis, 66 (78%) had a high cerebrospinal fluid protein concentration, and 80 (98%) of 82 had abnormal electroencephalographic findings. Thyroid function varied from overt hypothyroidism to overt hyperthyroidism; the most common abnormality was subclinical hypothyroidism (30 patients [35%]). Among patients treated with glucocorticoids, 66 (96%) improved.

CONCLUSIONS

The combination of encephalopathy, high serum antithyroid antibody concentrations, and responsiveness to glucocorticoid therapy seems unlikely to be due to chance. However, there is no evidence of a pathogenic role for the antibodies, which are probably markers of some other autoimmune disorder affecting the brain.

Delirium from nicotine withdrawal in neuro-ICU patients

Five cases of presumed nicotine withdrawal delirium among brain-injured patients treated in a neurologic intensive care unit are presented. Each patient had a history of heavy tobacco use and experienced dramatic and sustained clinical improvement within hours of transdermal nicotine replacement. These preliminary observations suggest that nicotine withdrawal may be an under-recognized cause of delirium in patients with acute brain injury.