The Greater Cincinnati/Northern Kentucky Stroke Study: preliminary first-ever and total incidence rates of stroke among blacks

Deaths from stroke in US young adults, 1989-2009

OBJECTIVE

To determine what the trends in stroke mortality have been over 2 decades in young adults.

METHODS

In this cohort study, we analyzed death certificate data for ischemic and hemorrhagic stroke (intracerebral hemorrhage [ICH] and subarachnoid hemorrhage [SAH]) in adults aged 20-44 in the United States for 1989 through 2009, covering approximately 2.2 billion person-years. Poisson regression was used to calculate and compare time trend data between groups and to compare trends in young adults to those in adults over age 45.

RESULTS

Mortality from stroke in young adults declined by 35% over the study period, with reductions in all 3 stroke subtypes (ischemic stroke decreased by 15%, ICH by 47%, and SAH by 50%). Black race was a risk factor for all 3 stroke subtypes (relative risk 2.4 for ischemic stroke, 4.0 for ICH, and 2.1 for SAH), but declines in all stroke subtypes were more dramatic in black compared to white participants (p < 0.001 for all stroke subtypes).

CONCLUSIONS

Although hospitalizations for stroke in young patients have been increasing, the apparent decrease in mortality rates and in racial disparities suggests that recognition and treatment in this group may be improving.

Outcomes of endovascular versus intravenous thrombolytic treatment for acute ischemic stroke in dialysis patients

BACKGROUND AND OBJECTIVES

To compare the outcomes of IV thrombolytics (tissue plasminogen activator or tPA) with endovascular treatment (intra-arterial tPA ± mechanical thrombectomy) in dialysis patients who suffered from acute ischemic stroke.

STUDY DESIGN

Observational study.

SETTING AND PARTICIPANTS

Data analysis from Nationwide Inpatient Sample (NIS 2005- 2010) including dialysis patients presenting with acute ischemic stroke, either treated with IV thrombolytics or endovascular treatment.

OUTCOMES

Baseline characteristics, in-hospital complications, and discharge outcomes were compared between the two groups. We determined the effect of endovascular treatment on in-hospital mortality, disability at discharge, and post-thrombolytic intracerebral hemorrhages (ICH) after adjusting for potential confounders using multivariate analysis.

RESULTS

Of the 2 313 dialysis patients with ischemic stroke, 1 398 (60%) received IV thrombolytics and 915 (40%) were treated with endovascular treatment. The in-hospital mortality rate and moderate-to-severe disability were lower in dialysis patients receiving endovascular treatment (7.6% vs. 14.5% p = 0.04) and (30% vs. 52% p = <.0001), respectively. After adjusting for age, gender, and potential confounders, endovascular treatment was associated with lower in-hospital mortality (OR 0.5, 95% CI 0.2-0.9) and moderate-to-severe disability (OR 0.3, 95% CI 0.2-0.5).

CONCLUSIONS

The odds of both in-hospital mortality and moderate to severe disability were lower with endovascular treatment in dialysis patients. Such data support the preferential use of endovascular treatment in this patient population.

Randomized controlled trial of yoga for chronic poststroke hemiparesis: motor function, mental health, and quality of life outcomes

PURPOSE

To assess the efficacy of yoga for motor function, mental health, and quality of life outcomes in persons with chronic poststroke hemiparesis.

METHOD

Twenty-two individuals participated in a randomized controlled trial involving assessment of task-orientated function, balance, mobility, depression, anxiety, and quality of life domains before and after either a 10-week yoga intervention (n = 11) or no treatment (n = 11).

RESULTS

The yoga intervention did not result in any significant improvements in objective motor function measures, however there was a significant improvement in quality of life associated with perceived motor function (P = .0001) and improvements in perceived recovery approached significance (P = .072). Memory-related quality of life scores significantly improved after yoga intervention (P = .022), and those participating in the intervention exhibited clinically relevant decreases in state and trait anxiety.

CONCLUSIONS

Preliminary results offer promise for yoga as an intervention to address mental health and quality of life in persons with stroke-related activity limitations. There is a need to more rigorously evaluate these yoga benefits with a larger randomized controlled trial, which, based on this preliminary trial, is feasible.

The adverse effect of spasticity on 3-month poststroke outcome using a population-based model

Several devices and medications have been used to address poststroke spasticity. Yet, spasticity's impact on outcomes remains controversial. Using data from a cohort of 460 ischemic stroke patients, we previously published a validated multivariable regression model for predicting 3-month modified Rankin Score (mRS) as an indicator of functional outcome. Here, we tested whether including spasticity improved model fit and estimated the effect spasticity had on the outcome. Spasticity was defined by a positive response to the question "Did you have spasticity following your stroke?" on direct interview at 3 months from stroke onset. Patients who had expired by 90 days (n = 30) or did not have spasticity data available (n = 102) were excluded. Spasticity affected the 3-month functional status (β = 0.420, 95 CI = 0.194 to 0.645) after accounting for age, diabetes, leukoaraiosis, and retrospective NIHSS. Using spasticity as a covariable, the model's R (2) changed from 0.599 to 0.622. In our model, the presence of spasticity in the cohort was associated with a worsened 3-month mRS by an average of 0.4 after adjusting for known covariables. This significant adverse effect on functional outcomes adds predictive value beyond previously established factors.

Stroke and active life expectancy in the United States, 1999-2009

BACKGROUND

Stroke reduces active life expectancy, both years lived and their proportion without disability. However, active life expectancy studies have provided limited information about strokes in the United States, those occurring throughout older life, or those affecting African Americans.

OBJECTIVE

To measure associations between strokes throughout older life and active life expectancy for African American and White women and men.

METHODS

Using data from the Panel Study of Income Dynamics, 1999-2009 (n = 1862, 13,603 person-years), we estimated monthly probabilities of death and disability in activities of daily living with multinomial logistic Markov models adjusted for age, sex, ethnicity, stroke in the past two years, earlier stroke, and education. A random effect accounted for the panel data repeated measures. Microsimulation created large populations with stroke incidence throughout older life, identifying life expectancy and the proportions of remaining life with and without disability. We matched individuals with strokes with randomly selected persons without strokes by age at first stroke, sex, ethnicity, and previous disability.

RESULTS

Average age at first stroke was higher for women, lower for African Americans. African American and White women were disabled for about two-thirds of life after stroke; results for men were 61.8% for African Americans and 37.2% for Whites. Compared to matched participants, those with strokes lived 33% fewer remaining years (95% confidence interval, CI 30.9%-34.7%) with a 31.6% greater proportion of remaining life with disability (CI 14.4%-55.6%).

CONCLUSIONS

Stroke greatly reduces both life expectancy and the proportion of life without disability, particularly for women and African Americans.

Validity of claims-based stroke algorithms in contemporary Medicare data: reasons for geographic and racial differences in stroke (REGARDS) study linked with medicare claims

BACKGROUND

The accuracy of stroke diagnosis in administrative claims for a contemporary population of Medicare enrollees has not been studied. We assessed the validity of diagnostic coding algorithms for identifying stroke in the Medicare population by linking data from the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study to Medicare claims.

METHODS AND RESULTS

The REGARDS Study enrolled 30 239 participants ≥45 years in the United States between 2003 and 2007. Stroke experts adjudicated suspected strokes, using retrieved medical records. We linked data for participants enrolled in fee-for-service Medicare to claims files from 2003 through 2009. Using adjudicated strokes as the gold standard, we calculated accuracy measures for algorithms to identify incident and recurrent strokes. We linked data for 15 089 participants, among whom 422 participants had adjudicated strokes during follow-up. An algorithm using primary discharge diagnosis codes for acute ischemic or hemorrhagic stroke (International Classification of Diseases, Ninth Revision, Clinical Modification codes: 430, 431, 433.x1, 434.x1, 436) had a positive predictive value of 92.6% (95% confidence interval, 88.8%-96.4%), a specificity of 99.8% (99.6%-99.9%), and a sensitivity of 59.5% (53.8%-65.1%). An algorithm using only acute ischemic stroke codes (433.x1, 434.x1, 436) had a positive predictive value of 91.1% (95% confidence interval, 86.6%-95.5%), a specificity of 99.8% (99.7%-99.9%), and a sensitivity of 58.6% (52.4%-64.7%).

CONCLUSIONS

Claims-based algorithms to identify stroke in a contemporary Medicare cohort had high positive predictive value and specificity, supporting their use as outcomes for etiologic and comparative effectiveness studies in similar populations. These inpatient algorithms are unsuitable for estimating stroke incidence because of low sensitivity.

Methodology for a community-based stroke preparedness intervention: the Acute Stroke Program of Interventions Addressing Racial and Ethnic Disparities Study

BACKGROUND AND PURPOSE

Acute stroke education has focused on stroke symptom recognition. Lack of education about stroke preparedness and appropriate actions may prevent people from seeking immediate care. Few interventions have rigorously evaluated preparedness strategies in multiethnic community settings.

METHODS

The Acute Stroke Program of Interventions Addressing Racial and Ethnic Disparities (ASPIRE) project is a multilevel program using a community-engaged approach to stroke preparedness targeted to underserved black communities in the District of Columbia. This intervention aimed to decrease acute stroke presentation times and increase intravenous tissue-type plasminogen activator utilization for acute ischemic stroke.

RESULTS

Phase 1 included (1) enhancement of focus of emergency medical services on acute stroke; (2) hospital collaborations to implement and enrich acute stroke protocols and transition District of Columbia hospitals toward primary stroke center certification; and (3) preintervention acute stroke patient data collection in all 7 acute care District of Columbia hospitals. A community advisory committee, focus groups, and surveys identified perceptions of barriers to emergency stroke care. Phase 2 included a pilot intervention and subsequent citywide intervention rollout. A total of 531 community interventions were conducted, reaching >10,256 participants; 3289 intervention evaluations were performed, and 19,000 preparedness bracelets and 14,000 stroke warning magnets were distributed. Phase 3 included an evaluation of emergency medical services and hospital processes for acute stroke care and a year-long postintervention acute stroke data collection period to assess changes in intravenous tissue-type plasminogen utilization.

CONCLUSIONS

We report the methods, feasibility, and preintervention data collection efforts of the ASPIRE intervention.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00724555.

Apolipoprotein E gene polymorphism and the risk of intracerebral hemorrhage: a meta-analysis of epidemiologic studies

Background

Studies investigating the association between the apolipoprotein E (APOE) gene polymorphism and the risk of intracerebral hemorrhage (ICH) have reported conflicting results. We here performed a meta-analysis based on the evidence currently available from the literature to make a more precise estimation of this relationship.

Methods

Published literature from the National Library of Medline and Embase databases were retrieved. Odds ratio (OR) and 95% confidence interval (CI) were calculated in fixed- or random-effects models when appropriate. Subgroup analyses were performed by race.

Results

This meta-analysis included 11 case–control studies, which included 1,238 ICH cases and 3,575 controls. The combined results based on all studies showed that ICH cases had a significantly higher frequency of APOE ϵ4 allele (OR= 1.42, 95% CI= 1.21,1.67, P<0.001). In the subgroup analysis by race, we also found that ICH cases had a significantly higher frequency of APOE ϵ4 allele in Asians (OR= 1.52, 95% CI= 1.20,1.93, P<0.001) and in Caucasians (OR= 1.34, 95% CI= 1.07,1.66, P=0.009). There was no significant relationship between APOE ϵ2 allele and the risk of ICH.

Conclusion

Our meta-analysis suggested that APOE ϵ4 allele was associated with a higher risk of ICH.

Angioplasty and stenting of intracranial atherosclerosis with the Wingspan system: 1-year clinical and radiological outcome in a single Asian center

BACKGROUND

This study aimed to evaluate the 1-year clinical and angiographic outcome of angioplasty and stenting of intracranial atherosclerosis using Wingspan and Gateway system.

METHODS

In this prospective study, patients with symptomatic lesions were treated and followed clinically and angiographically by digital subtraction angiography (DSA) for 1 year. The two primary endpoints were recurrent ipsilateral ischemic stroke and in-stent restenosis (ISR) at 1 year. Secondary endpoints included periprocedural death or stroke and all strokes at 1 year. Potential factors correlated with ISR were studied using univariate and multivariate analysis.

RESULTS

Treatment was attempted in 65 patients and successfully completed in 61 (93.8%). Fifty-nine patients (44 men, 15 women) aged 62.86 ± 11.38 years with 66 stenoses (average degree of stenosis 71.78 ± 11.23%) underwent clinical and DSA follow-up at 1 year. There were 66 stenotic lesions. ISR occurred in 11 of the 66 lesions (16.7%). Luminal gain occurred in 32 of the lesions (48.5%), an unchanged lumen in 4 (6%) and luminal loss in 30 (45.4%). The periprocedural stroke or death rate was 6.1% (4/65), including three hemorrhagic and one ischemic stroke, all of which occurred at the corresponding site and resulted in death. There were no interval strokes between the periprocedural time and the 1-year follow-up. The occurrence of ISR was correlated with the degree of stenosis before treatment and was not correlated with patient age or sex, vessel diameter, location of stenosis or failure to control risk factors for atherosclerosis.

CONCLUSIONS

One-year clinical and angiographic outcomes of angioplasty and stenting are promising for symptomatic intracranial atherosclerosis.

Validation of Diagnostic and Procedural Codes for Identification of Acute Cardiovascular Events in US Veterans with Rheumatoid Arthritis

Objective:

To assess the accuracy of International Classification of Diseases, Ninth Revision, and Current Procedural Terminology codes for identifying cardiovascular (CV) events (myocardial infarction [MI], stroke, coronary artery bypass graft [CABG], and percutaneous coronary intervention [PCI]) in enrollees of the Veterans Affairs Rheumatoid Arthritis (VARA) registry.

Design:

We performed a validation study from VARA enrollment until 6/1/2010 to compare the accuracy of CV events in those with and without CV-event coding in inpatient and outpatient records to evaluate for CV events +/− 3 months of the coding. The positive predictive value (PPV) was calculated, and codes with a PPV ≥50% were included in a composite coding algorithm.

Results:

We evaluated 107 individuals for 21 CV-event codes and 60 individuals without CV-event coding. The PPV varied between 0–100%. Composite coding algorithms’ PPV ranged from 70–100%.

Conclusions:

Validation of these algorithms allows for identification of acute CV events with known accuracy. The sensitivity and PPV of coding algorithms for CABG and PCI exceed that of stroke and MI.

Early and intermediate prognosis of intravenous thrombolytic therapy in acute ischemic stroke subtypes according to the causative classification of stroke system

Objectives: Intravenous thrombolytic therapy has established acceptable results in treating ischemic stroke. However, there is little information on treatment outcome especially in different subtypes. The aim of current study was to evaluate early and intermediate prognosis in intravenous thrombolytic therapy for acute ischemic stroke subtypes.

Methodology: Forty eligible patients (57.5% male with mean age of 63.18±13.49 years) with definite ischemic stroke who were admitted to emergency department of Imam Reza University Hospital, in the first 180 minutes after occurrence received recombinant tissue plasminogen activator. All investigation findings were recorded and stroke subtypes were determined according to the Causative Classification of Stroke System. Stroke severity forms including modified Rankin Scale (mRS) and National Institutes of Health Stroke Scale (NIHSS) scores were recorded for all patients in first, seven and 90 days after stroke and disease outcome was evaluated.

Results: The etiology of stroke was large artery atherosclerosis in 20%, cardio-aortic embolism in 45%, small artery occlusion in 17.5% and undetermined causes in 17.5%. NIHSS and mRS scores were significantly improved during time (P < 0.001 in both cases). Three months mortality rate was 25%. Among the etiologies, patients with small artery occlusion and then cardio-aortic embolism had lower NIHSS score at arrival (P = 0.04). Caplan-meier analysis showed that age, sex and symptom to needle time could predict disease outcome.

Conclusion: Intravenous thrombolytic therapy is accompanied by good early and intermediate outcome in most patients with ischemic stroke. Small artery occlusion subtype had less disease severity and higher improvement.

The mirror neuron system in post-stroke rehabilitation

Different treatments for stroke patients have been proposed; among them the mirror therapy and motion imagery lead to functional recovery by providing a cortical reorganization. Up today the basic concepts of the current literature on mirror neurons and the major findings regarding the use of mirror therapy and motor imagery as potential tools to promote reorganization and functional recovery in post-stroke patients. Bibliographic research was conducted based on publications over the past thirteen years written in English in the databases Scielo, Pubmed/MEDLINE, ISI Web of Knowledge. The studies showed how the interaction among vision, proprioception and motor commands promotes the recruitment of mirror neurons, thus providing cortical reorganization and functional recovery of post-stroke patients. We conclude that the experimental advances on Mirror Neurons will bring new rational therapeutic approaches to post-stroke rehabilitation.

Intima-media thickness of the carotid arteries is related to serum osteoprotegerin levels in healthy postmenopausal women

Osteoprotegerin (OPG) regulates bone mass by inhibiting osteoclast differentiation and activation, and also plays a role in vascular calcification. The objective of this study was to evaluate the relationship between serum OPG levels, and carotid artery intima-media thickness (IMT) and carotid plaque formation in healthy postmenopausal women. We recruited 68 healthy postmenopausal women for the study. Carotid plaque presence and IMT were evaluated by high resolution B-mode ultrasound. IMT was positively correlated with presence of plaque, age, menopause age and OPG, and inversely correlated with Apolipoprotein A1 (Apo A1). Serum OPG level was positively correlated with IMT (r = 0.366; p < 0.003) and age (r = 0.324; p < 0.008), and negatively correlated with Apo A1 (r = -0.481; p < 0.0001). We did not observe any significant relation between plaque occurrence and levels of serum OPG. In regression analysis OPG (p < 0.02) and menopause age (p < 0.05) were independent risk factors for IMT, and age (p < 0.05) and IMT (p < 0.05) were independent risk factors for plaque formation. Although the role of OPG in the vascular biology is poorly understood, our results suggest that elevated levels of serum OPG is associated with IMT and may play a role in the pathogenesis of atherosclerotic disease.

Diabetes mellitus: a risk factor for ischemic stroke in a large biracial population

BACKGROUND AND PURPOSE

We previously reported increased incidence of ischemic stroke among both blacks and whites with diabetes mellitus, especially in those aged <55 years. With rising prevalence of diabetes mellitus in the past decade, we revisit the impact of diabetes mellitus on stroke incidence in the same population (≈1.3 million) 5 and 10 years later.

METHODS

This is a population-based study. First ischemic strokes among black and white residents of the 5-county Greater Cincinnati/Northern Kentucky region, aged ≥ 20 years, for periods 7/1993 to 6/1994, 1999, and 2005, were included in this analysis. Incidence rates were adjusted for sex, race, and age, as appropriate, to the 2000 US population.

RESULTS

History of diabetes mellitus among first ischemic strokes was reported for 493/1709 (28%) in 1993/1994, 522/1778 (29%) in 1999, and 544/1680 (33%) in 2005. Risk ratios (95% confidence interval) for rates of stroke in those with versus without diabetes mellitus for blacks reduced significantly from 5.6 in 1993/1994 to 3.2 in 2005; for whites the risk ratio remained stable at 3.8 in 1993/1994 and 2005. However, risk ratios varied with age, with an overall 5- to 14-fold increased risk observed in those aged 20 to 65 years.

CONCLUSIONS

Those with diabetes mellitus remain at greatly increased risk for stroke at all ages, especially <65 years, regardless of race. The rates and risk ratios for 1999 and 2005, although similar to those previously reported for the mid-1990s, take on increased significance, given the epidemic of diabetes mellitus and metabolic syndrome throughout the US and the world.

Profiles of the National Institutes of Health Stroke Scale items as a predictor of patient outcome

BACKGROUND AND PURPOSE

Initial National Institutes of Health Stroke Scale (NIHSS) score is highly predictive of outcome after ischemic stroke. We examined whether grouping strokes by presence of individual NIHSS symptoms could provide prognostic information additional or alternative to the NIHSS total score.

METHODS

Ischemic strokes from the Greater Cincinnati Northern Kentucky Stroke Study in 2005 were used to develop the model. Latent class analysis was implemented to form groups of patients with similar retrospective NIHSS (rNIHSS) item responses. Profile group was then used as an independent predictor of discharge modified Rankin and mortality, using logistic regression and Cox proportional hazards model.

RESULTS

A total of 2112 stroke patients were identified in 2005. Six distinct profiles were characterized. Consistent with the profile patterns, the median rNIHSS total score decreased from profile A "most severe" (median [interquartile range], 20 [15-25]) to profile F "mild" (1[1-2]). Two profiles falling between these extremes, C and D, both had median rNIHSS total score of 5, but different survival rates. Compared with A, C was associated with 59% risk reduction for death, whereas D with 70%. C patients were more likely to have decreased level of consciousness and abnormal language, whereas D patients were more likely to have abnormal right arm and right leg motor function.

CONCLUSIONS

Six rNIHSS profiles were identifiable using latent class analysis. In particular, 2 symptom profiles with identical median rNIHSSS were observed with widely disparate outcomes, which may prove useful both clinically and for research studies as an enhancement to the overall NIHSS score.

Learning curve of Wingspan stenting for intracranial atherosclerosis: single-center experience of 95 consecutive patients

Background

Symptomatic brain hemorrhage was a significant cause of periprocedural stroke or death following stenting in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis trial, which called into question the safety of Wingspan stenting for intracranial atherosclerosis. This study analyzed the role of a learning curve in the safety and outcome of Wingspan stenting from the experience of 95 consecutive patients at a single center.

Methods

In this prospective study the endpoints were major stroke or death (modified Rankin Scale score >3) within 30 days, other neurological complications, technical procedural problems, technical success in completion of angioplasty and stenting and recurrent ischemic stroke in the corresponding vascular territory after 30 days. Data splitting into quarters was used for learning curve analysis.

Results

The periprocedural major stroke or death rate was 4.2% (4/95), minor stroke rate was 5.3% (5/95), total 9.5% (9/95). The technical procedural problem rate was 11.6% (11/95) and the technical success rate was 93.7% (89/95). The 89 patients were followed for 38.9±22.7 months (median 40.8, range 0.2–72, 3463 patient-months) after stenting. The risk of recurrent ischemic stroke in the corresponding vascular territory was 0.7% per patient per year (2/3463 patient-months). Guidewire- or angioplasty-related hemorrhage was the major cause of periprocedural major stroke or death (3/4, 75%) and did not occur in the last quarter. Periprocedural intracerebral hemorrhage was uncommon and perforator stroke did not occur.

Conclusions

There may be a learning curve for mastering the safety precautions of Wingspan stenting for intracranial atherosclerosis.

Amphetamines, atomoxetine and the risk of serious cardiovascular events in adults

Main Objective

To compare the incidence rates of serious cardiovascular events in adult initiators of amphetamines or atomoxetine to rates in non-users.

Methods

This was a retrospective cohort study of new amphetamines (n = 38,586) or atomoxetine (n = 20,995) users. Each medication user was matched to up to four non-users on age, gender, data source, and state (n = 238,183). The following events were primary outcomes of interest 1) sudden death or ventricular arrhythmia, 2) stroke, 3) myocardial infarction, 4) a composite endpoint of stroke or myocardial infarction. Cox proportional hazard regression was used to calculate propensity-adjusted hazard ratios for amphetamines versus matched non-users and atomoxetine versus matched non-users, with intracluster dependence within matched sets accounted for using a robust sandwich estimator.

Results

The propensity-score adjusted hazard ratio for amphetamines use versus non-use was 1.18 (95% CI: 0.55–2.54) for sudden death/ventricular arrhythmia, 0.80 (95% CI: 0.44–1.47) for stroke, 0.75 (95% CI: 0.42–1.35) for myocardial infarction, and 0.78 (95% CI: 0.51–1.19) for stroke/myocardial infarction. The propensity-score adjusted hazard ratio for atomoxetine use versus non-use was 0.41 (95% CI: 0.10–1.75) for sudden death/ventricular arrhythmia, 1.30 (95% CI: 0.52–3.29) for stroke, 0.56 (95% CI: 0.16–2.00) for myocardial infarction, and 0.92 (95% CI: 0.44–1.92) for stroke/myocardial infarction.

Conclusions

Initiation of amphetamines or atomoxetine was not associated with an elevated risk of serious cardiovascular events. However, some of the confidence intervals do not exclude modest elevated risks, e.g. for sudden death/ventricular arrhythmia.

Factors and outcomes associated with early and delayed aneurysm treatment in subarachnoid hemorrhage patients in the United States

BACKGROUND

Recent studies from selected centers have shown that early surgical treatment of aneurysms in subarachnoid hemorrhage (SAH) patients can improve outcomes. These results have not been validated in clinical practice at large.

OBJECTIVE

To identify factors and outcomes associated with timing of ruptured intracranial aneurysm obliteration treatment in patients with SAH after hospitalization in the United States.

METHODS

We analyzed the data from the Nationwide Inpatient Sample (2005-2008) for all patients presenting with primary diagnosis of SAH, receiving aneurysm treatment (endovascular coil embolization or surgical clip placement). Early treatment was defined as aneurysm treatment performed within 48 hours and delayed treatment if treatment was performed after 48 hours of admission.

RESULTS

Of 32 048 patients with SAH who underwent aneurysm treatment, 24 085 (75.2%) underwent early treatment and 7963 (24.8%) underwent delayed treatment. Female sex (P = .002), endovascular embolization (P < .001), and weekday admission (P < .001) were independent predictors of early treatment. In the early treatment group, patients were more likely discharged with none to minimal disability (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.14-1.47) and less likely to be discharged with moderate to severe disability (OR 0.77, 95%CI 0.67-0.87) compared with those in the delayed treatment group. The in-hospital mortality was higher in the early treatment group compared with the delayed treatment group (OR 1.36 95%CI 1.12-1.66).

CONCLUSION

Patients with SAH who undergo aneurysm treatment within 48 hours of hospital admission are more likely to be discharged with none to minimal disability. Early treatment is more likely to occur in those undergoing endovascular treatment and in patients admitted on weekdays.

Surgical results of the Carotid Occlusion Surgery Study

OBJECT

The Carotid Occlusion Surgery Study (COSS) was conducted to determine if superficial temporal artery-middle cerebral artery (STA-MCA) bypass, when added to the best medical therapy, would reduce subsequent ipsilateral stroke in patients with complete internal carotid artery (ICA) occlusion and an elevated oxygen extraction fraction (OEF) in the cerebral hemisphere distal to the occlusion. A recent publication documented the methodology of the COSS in detail and briefly outlined the major findings of the trial. The surgical results of the COSS are described in detail in this report.

METHODS

The COSS was a prospective, parallel-group, 1:1 randomized, open-label, blinded-adjudication treatment trial. Participants, who had angiographically demonstrated complete occlusion of the ICA causing either a transient ischemic attack or ischemic stroke within 120 days and hemodynamic cerebral ischemia indicated by an increased OEF measured by PET, were randomized to either surgical or medical treatment. One hundred ninety-five patients were randomized: 97 to the surgical group and 98 to the medical group. The surgical patients underwent an STA-MCA cortical branch anastomosis.

RESULTS

In the intention-to-treat analysis, the 2-year rates for the primary end point were 21% for the surgical group and 22.7% for the medical group (p = 0.78, log-rank test). Fourteen (15%) of the 93 patients who had undergone an arterial bypass had a primary end point ipsilateral hemispheric stroke in the 30-day postoperative period, 12 within 2 days after surgery. The STA-MCA arterial bypass patency rate was 98% at the 30-day postoperative visit and 96% at the last follow-up examination. The STA-MCA arterial bypass markedly improved, although it did not normalize, the level of elevated OEF in the symptomatic cerebral hemisphere. Five surgically treated and 1 nonsurgically treated patients in the surgical group had a primary end point ipsilateral hemispheric stroke after the 30-day postoperative period. No baseline characteristics or intraoperative variables revealed those who would experience a procedure-related stroke.

CONCLUSIONS

Despite excellent bypass graft patency and improved cerebral hemodynamics, STA-MCA anastomosis did not provide an overall benefit regarding ipsilateral 2-year stroke recurrence, mainly because of a much better than expected stroke recurrence rate (22.7%) in the medical group, but also because of a significant postoperative stroke rate (15%). Clinical trial registration no.: NCT00029146.

Malignant MCA territory infarction in the pediatric population: subgroup analysis of the Greater Cincinnati/Northern Kentucky Stroke Study

PURPOSE

Malignant middle cerebral artery (MCA) infarctions are thought to be rare in children. In a recent hospital-based study, only 1.3 % of pediatric ischemic strokes were malignant MCA infarctions. However, population-based rates have not been published. We performed subgroup analysis of a population-based study to determine the rate of malignant MCA infarctions in children.

METHODS

In 2005 and 2010, all ischemic stroke-related emergency visits and hospital admissions among the 1.3 million residents of the five-county Greater Cincinnati/Northern Kentucky area were ascertained. Cases that occurred in patients 18 years and younger were reviewed in detail, and corresponding clinical and neuroimaging findings were recorded. Infarctions were considered malignant if they involved 50 % or more of the MCA territory and resulted in cerebral edema and mass effect.

RESULTS

In 2005, eight pediatric ischemic strokes occurred in the study population, none of which were malignant infarctions. In 2010, there were also eight ischemic strokes. Of these, two malignant MCA infarctions were identified: (1) a 7-year-old boy who underwent hemicraniectomy and survived with moderate disability at 30 days and (2) a 17-year-old girl with significant prestroke disability who was not offered hemicraniectomy and died following withdrawal of care. Thus, among 16 children over 2 years, there were two malignant MCA infarctions (12.5 %, 95 % CI 0-29).

CONCLUSIONS

Malignant MCA infarctions in children may not be as rare as previously thought. Given the significant survival and functional outcome benefit conferred by hemicraniectomy in adults, future studies focusing on its potential role in pediatric patients are warranted.

Trends in substance abuse preceding stroke among young adults: a population-based study

BACKGROUND AND PURPOSE

Approximately 5% of strokes occur in adults aged 18 to 44 years. Substance abuse is a prevalent risk factor for stroke in young adults. We sought to identify trends in substance abuse detection among stroke patients.

METHODS

Using a population-based design, we sought to identify all patients aged 18 to 54 years experiencing a stroke (ischemic or hemorrhagic) in the Greater Cincinnati and Northern Kentucky Study region during 1993 to 1994, 1999, and 2005. Demographic and clinical characteristics and substance use data were obtained retrospectively from chart review and adjudicated by physicians.

RESULTS

The number of young patients identified with a stroke increased from 1993 to 1994 (297) to 2005 (501). Blacks (61% vs 51%; P<0.02) and men (61% vs 47%; P<0.002) reported substance abuse (current smoking, alcohol, or illegal drug use) more frequently than did whites and women. Overall use of substances increased across study periods, 45% in 1993 versus 62% in 2005 (P=0.003). The trend was significant for illegal drug use (3.8% in 1993 vs 19.8% in 2005) and ever smoking (49% in 1993 vs 66% in 2005). Documentation of both cocaine and marijuana use increased over time. In 2005, half of young adults with a stroke were current smokers, and 1 in 5 abused illegal drugs.

CONCLUSIONS

Substance abuse is common in young adults experiencing a stroke. The observed increase in substance abuse is contributing to the increased incidence of stroke in young adults. Patients aged younger than 55 years who experience a stroke should be routinely screened and counseled regarding substance abuse.

Arm stiffness during assisted movement after stroke: the influence of visual feedback and training

Spasticity and muscular hypertonus are frequently found in stroke survivors and may have a significant effect on functional impairment. These abnormal neuro-muscular properties, which are quantifiable by the net impedance of the hand, have a direct consequence on arm mechanics and are likely to produce anomalous motor paths. Literature studies quantifying limb impedance in stroke survivors have focused on multijoint static tasks and single joint movements. Despite this research, little is known about the role of sensory motor integration in post-stroke impedance modulation. The present study elucidates this role by integrating an evaluation of arm impedance into a robotically mediated therapy protocol. Our analysis had three specific objectives: 1) obtaining a reliable measure for the mechanical proprieties of the upper limb during robotic therapy; 2) investigating the effects of robot-assisted training and visual feedback on arm stiffness and viscosity; 3) determining if the stiffness measure and its relationship with either training or visual feedback depend on arm position, speed, and level of assistance. This work demonstrates that the performance improvements produced by minimally assistive robot training are associated with decreased viscosity and stiffness in stroke survivors' paretic arm and that these mechanical impedance components are partially modulated by visual feedback.

Experimental validation of a finite-difference model for the prediction of transcranial ultrasound fields based on CT images

The prevalence of stroke worldwide and the paucity of effective therapies have triggered interest in the use of transcranial ultrasound as an adjuvant to thrombolytic therapy. Previous studies have shown that 120 kHz ultrasound enhanced thrombolysis and allowed efficient penetration through the temporal bone. The objective of our study was to develop an accurate finite-difference model of acoustic propagation through the skull based on computed tomography (CT) images. The computational approach, which neglected shear waves, was compared with a simple analytical model including shear waves. Acoustic pressure fields from a two-element annular array (120 and 60 kHz) were acquired in vitro in four human skulls. Simulations were performed using registered CT scans and a source term determined by acoustic holography. Mean errors below 14% were found between simulated pressure fields and corresponding measurements. Intracranial peak pressures were systematically underestimated and reflections from the contralateral bone were overestimated. Determination of the acoustic impedance of the bone from the CT images was the likely source of error. High correlation between predictions and measurements (R(2) = 0.93 and R(2) = 0.88 for transmitted and reflected waves amplitude, respectively) demonstrated that this model is suitable for a quantitative estimation of acoustic fields generated during 40-200 kHz ultrasound-enhanced ischemic stroke treatment.

Angioplasty and stenting for intracranial atherosclerotic stenosis with nitinol stent: factors affecting technical success and patient safety

BACKGROUND

Angioplasty and stenting using nitinol stents is a recognized treatment option for intracranial atherosclerosis.

OBJECTIVE

To identify procedure-related factors that may affect patient safety and technical outcome.

METHODS

In this prospective study of 57 consecutive patients, the primary end points were intraprocedural technical problems, periprocedure morbidity, and complications. Major periprocedure complication was defined as all stroke or death at 30 days. Technical failure was defined as the inability to complete the procedure because of technical or safety problems. Procedure failure was defined as a procedure outcome of technical failure or major periprocedure complication. Secondary end points were procedure-related factors that may affect patient safety and technical outcome.

RESULTS

Procedure failure rate was 12.3% (7/57) (major periprocedure complication rate, 5.3% [3/57]; technical failure rate, 7% [4/57]). Initial failure in tracking of balloon or stent occurred in 20 patients, other technical problems occurred in 11 patients, including kinking or trapping of balloon catheter (2 cases), difficulty in unsheathing of stent (3 cases), forward migration of stent during deployment (4 cases), trapping of nose cone after stent deployment (1 case), fracture of delivery system (2 cases), and guidewire fracture (1 case). Unfavorable vascular morphology signified by the presence of 2 or more reverse curves along the access path was found to associate with initial failure in the tracking of instruments (OR = ∞), and occurrence of other technical problems (OR = 25).

CONCLUSION

Procedure-related factors could be identified and lead to improvements in patient safety and technical outcome. Tortuous vascular morphology is a key factor to be overcome.

Efficiency of enrollment in a successful phase II acute stroke clinical trial

BACKGROUND

Recruitment challenges are common in acute stroke clinical trials. In a population-based study, we determined eligibility and actual enrollment for a successful, phase II acute stroke clinical trial. We hypothesized that missed opportunities for enrollment of eligible patients occurred frequently, despite the success of the trial.

METHODS

In 2005, acute ischemic stroke (AIS) cases in our region were identified at all 17 local hospitals as part of an epidemiologic study. The Combined Approach to Lysis Utilizing Eptifibatide and Recombinant Tissue Plasminogen Activator (CLEAR) trial assessed the safety of this combination in AIS patients within 3 hours of symptom onset. In 2005, we determined the proportion of AIS patients who were eligible for CLEAR and the proportion that were actually enrolled.

RESULTS

At 8 participating hospitals, 33 (2.8%) of 1175 AIS patients were eligible for CLEAR. Of 33 eligible patients, 18 (54.5%) were approached for enrollment, 4 (12.1%) refused, 1 (3.0%) was not consentable, and 13 (39.4%) were enrolled. Of the 15 not approached for enrollment in the trial, 10 were evaluated by the stroke team; 7 received recombinant tissue plasminogen activator. Enrollment was not associated with night or weekend presentation.

CONCLUSIONS

Although the CLEAR trial was successful in meeting its delineated recruitment goals, our findings suggest enrollment could have been more efficient. Three out of 4 patients approached for enrollment participated in the trial. Eligible patients who were not approached and those treated with recombinant tissue plasminogen activator but not enrolled represent targets for improving enrollment rates.

Neural stem cells and stroke

Acute ischemic stroke causes a disturbance of neuronal circuitry and disruption of the blood-brain barrier that can lead to functional disabilities. At present, thrombolytic therapy inducing recanalization of the occluded vessels in the cerebral infarcted area is a commonly used therapeutic strategy. However, only a minority of patients have timely access to this kind of therapy. Recently, neural stem cells (NSCs) as therapy for stroke have been developed in preclinical studies. NSCs are harbored in the subventricular zone (SVZ) as well as the subgranular zone of the brain. The microenvironment in the SVZ, including intercellular interactions, extracellular matrix proteins, and soluble factors, can promote NSC proliferation, self-renewal, and multipotency. Endogenous neurogenesis responds to insults of ischemic stroke supporting the existence of remarkable plasticity in the mammalian brain. Homing and integration of NSCs to the sites of damaged brain tissue are complex morphological and physiological processes. This review provides an update on current preclinical cell therapies for stroke, focusing on neurogenesis in the SVZ and dentate gyrus and on recruitment cues that promote NSC homing and integration to the site of the damaged brain.

Age at stroke: temporal trends in stroke incidence in a large, biracial population

OBJECTIVES

We describe temporal trends in stroke incidence stratified by age from our population-based stroke epidemiology study. We hypothesized that stroke incidence in younger adults (age 20-54) increased over time, most notably between 1999 and 2005.

METHODS

The Greater Cincinnati/Northern Kentucky region includes an estimated population of 1.3 million. Strokes were ascertained in the population between July 1, 1993, and June 30, 1994, and in calendar years 1999 and 2005. Age-, race-, and gender-specific incidence rates with 95 confidence intervals were calculated assuming a Poisson distribution. We tested for differences in age trends over time using a mixed-model approach, with appropriate link functions.

RESULTS

The mean age at stroke significantly decreased from 71.2 years in 1993/1994 to 69.2 years in 2005 (p < 0.0001). The proportion of all strokes under age 55 increased from 12.9% in 1993/1994 to 18.6% in 2005. Regression modeling showed a significant change over time (p = 0.002), characterized as a shift to younger strokes in 2005 compared with earlier study periods. Stroke incidence rates in those 20-54 years of age were significantly increased in both black and white patients in 2005 compared to earlier periods.

CONCLUSIONS

We found trends toward increasing stroke incidence at younger ages. This is of great public health significance because strokes in younger patients carry the potential for greater lifetime burden of disability and because some potential contributors identified for this trend are modifiable.

Epidemiology and risk factors

PURPOSE OF REVIEW

: This article presents current knowledge on stroke epidemiology. It covers recent data on the global burden of stroke, disparities, silent stroke, traditional and novel risk factors, and stroke triggers as well as the clinical implications of these findings.

RECENT FINDINGS

: Stroke is the third leading cause of death and the leading cause of chronic disability in the United States, and the burden of stroke worldwide is even greater. Large international and US case-control and prospective cohort studies have demonstrated disparities in stroke mortality and incidence. They have also shed light on the relative importance of several well-established, modifiable risk factors for ischemic stroke, such as hypertension, atrial fibrillation, other cardiac diseases, hyperlipidemia, diabetes, cigarette smoking, physical inactivity, alcohol consumption, abdominal obesity, diet, and TIA. Research on other putative stroke risk factors (including inflammation, infection, renal disease, depression, stress, and others) is ongoing. Identifying stroke triggers may be another way to minimize stroke incidence if high-risk time windows can be determined.

SUMMARY

: Stroke is a major global health burden. While many of the risk factors for stroke are well known and have been studied for decades, recent studies continue to shed light on the distribution and severity of these problems.

Ultrasound Evaluation of Mechanical Properties of Individual Muscles-Tendons during Active Contraction

A new method to accurately measure the mechanical properties of individual muscles and tendons under active contraction is presented. An individual muscle is activated selectively to different intensities through electrical stimulation with adjustable amplitude, frequency, and pulse width. During the course of active contraction of the stimulated muscle, muscle fiber pennation angle, muscle fascicle length, tendon length are measured by ultrasonography in vivo and non-invasively. The force produced by the stimulated muscle is derived from the measured joint torque and the moment arm recorded by a 3-D motion tracking system. The relationship between the force produced by the selected individual muscle and the muscle and tendon architectural parameters are studied quantitatively for the flexor carpi ulnaris and flexor carpi radialis.

Racial differences in albuminuria, kidney function, and risk of stroke

BACKGROUND

The objective of this study was to examine the joint associations of estimated glomerular filtration rate (eGFR) and urinary albumin excretion with incident stroke in a large national cohort study.

METHODS

Associations of urinary albumin to creatinine ratio (ACR) and eGFR with incident stroke were examined in 25,310 participants of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a prospective study of black and white US adults ≥45 years of age.

RESULTS

A total of 548 incident strokes were observed over a median of 4.7 years of follow-up. Higher ACR values were associated with lower stroke-free survival in both black and white participants. Among black participants, as compared to an ACR <10 mg/g, the hazard ratios of stroke associated with an ACR of 10-29.99, 30-300, and >300 mg/g were 1.41 (95% confidence interval [CI] 1.01-1.98), 2.10 (95% CI 1.48-2.99), and 2.70 (95% CI 1.58-4.61), respectively, in analyses adjusted for traditional stroke risk factors and eGFR. In contrast, the hazard ratios among white subjects were only modestly elevated and not statistically significant after adjustment for established stroke risk factors. eGFR <60 mL/min/1.73 m(2) was not associated with incident stroke in black or white participants after adjustment for established stroke risk factors.

CONCLUSIONS

Higher ACR was independently associated with higher risk of stroke in black but not white participants from a national cohort. Elucidating the reasons for these findings may uncover novel mechanisms for persistent racial disparities in stroke.

National trends in utilization and outcomes of endovascular treatment of acute ischemic stroke patients in the mechanical thrombectomy era

BACKGROUND AND PURPOSE

Because several new devices for mechanical thrombectomy have become available, the outcomes of patients undergoing endovascular treatment for acute ischemic stroke are expected to improve in the United States. We performed this analysis to evaluate trends in utilization of endovascular treatment and associated rates of death and disability among acute ischemic stroke patients over a 6-year period, including further assessment within age strata.

METHODS

We obtained data for patients admitted to hospitals in the United States from 2004 to 2009 with a primary diagnosis of ischemic stroke using a large national database. We determined the rate and pattern of utilization, and associated in-hospital outcomes of endovascular treatment among ischemic stroke patients and further analyzed trends within age strata. Outcomes were classified as minimal disability, moderate to severe disability, and death based on discharge disposition and compared between 2 time periods: 2004 to 2007 (post-MERCI) and 2008 to 2009 (post-Penumbra) approvals

RESULTS

Of the 3,292,842 patients admitted with ischemic stroke, 72,342 (2.2%) received intravenous thrombolytic treatment and 13 799 (0.4%) underwent endovascular treatment. There was a 6-fold increase in patients who underwent endovascular treatment (0.1% of ischemic strokes in 2004 vs 0.6% in 2009; P<0.001), with the patients aged≥85 years having the lowest rate of utilization (0.2%). The rates of intracranial hemorrhage remained unchanged throughout the 6 years. In multivariate logistic regression analysis, after adjusting for age, gender, presence of hypertension, congestive heart failure, renal failure, and secondary intracranial hemorrhages, there was no difference in the rate of minimal disability between the 2 study intervals (2004-2007 vs 2008-2009; odds ratio, 0.8; 95% confidence interval, 0.7-1.04; P=0.11). Mortality decreased while moderate to severe disability increased for patients treated during 2008 to 2009 (odds ratio, 0.7; 95% confidence interval, 0.6-0.9; P=0.007; and odds ratio, 1.4; 95% confidence interval, 1.2-1.7; P=0.0002).

CONCLUSIONS

There has been a significant increase in the proportion of acute ischemic stroke patients receiving endovascular treatment over the 6 years and reduction in in-hospital mortality. Our results highlight the need to implement endovascular techniques in a balanced manner across various age groups that also results in the reduction of disability in addition to mortality.

Elements of a stroke center

The past decade has ushered in a refined understanding of--and commitment to--objective evidence-based practice of stroke management. Responding to the need for universal protocol-driven guidelines for stroke care, the Brain Attack Coalition published consensus statements with recommendations for primary stroke centers (Alberts MJ, et al, JAMA 283:3102-3109, 2000) and comprehensive stroke centers (Alberts MJ, et al, Stroke 36:1597-1616, 2005) in 2000 and 2005, respectively. These benchmark publications helped to define a new "standard of care" for stroke patients and laid the groundwork to establish formal certification for stroke centers. Although large randomized controlled trials evaluating the efficacy of these guidelines are currently underway, several recent reports suggest that stroke center certification may improve outcomes in patients with acute ischemic stroke. In this article, the authors briefly discuss the status of stroke center certification and the evolution of stroke systems of care.

Patients living in impoverished areas have more severe ischemic strokes

BACKGROUND AND PURPOSE

Initial stroke severity is one of the strongest predictors of eventual stroke outcome. However, predictors of initial stroke severity have not been well-described within a population. We hypothesized that poorer patients would have a higher initial stroke severity on presentation to medical attention.

METHODS

We identified all cases of hospital-ascertained ischemic stroke occurring in 2005 within a biracial population of 1.3 million. "Community" socioecomic status was determined for each patient based on the percentage below poverty in the census tract in which the patient resided. Linear regression was used to model the effect of socioeconomic status on stroke severity. Models were adjusted for race, gender, age, prestroke disability, and history of medical comorbidities.

RESULTS

There were 1895 ischemic stroke events detected in 2005 included in this analysis; 22% were black, 52% were female, and the mean age was 71 years (range, 19-104). The median National Institutes of Health Stroke Scale was 3 (range, 0-40). The poorest community socioeconomic status was associated with a significantly increased initial National Institutes of Health Stroke Scale by 1.5 points (95% confidence interval, 0.5-2.6; P<0.001) compared with the richest category in the univariate analysis, which increased to 2.2 points after adjustment for demographics and comorbidities.

CONCLUSIONS

We found that increasing community poverty was associated with worse stroke severity at presentation, independent of other known factors associated with stroke outcomes. Socioeconomic status may impact stroke severity via medication compliance, access to care, and cultural factors, or may be a proxy measure for undiagnosed disease states.

Role of magnesium sulfate in neuroprotection in acute ischemic stroke

AIMS

To study the effect of intravenous magnesium sulfate infusion on clinical outcome of patients of acute stroke.

MATERIALS AND METHODS

Sixty consecutive cases of acute ischemic stroke hospitalised within 24 h of an episode of stroke were taken as subjects. All subjects underwent a computed tomography head, and those found to have evidence of bleed/space-occupying lesions were excluded from the study. The subjects taken up for the study were divided into two groups of 30 subjects each. Both the groups received the standard protocol management for acute ischemic stroke. Subjects of Group 1 additionally received intravenous magnesium sulfate as initial 4 g bolus dose over 15 min followed by 16 g as slow infusion over the next 24 h. In all the subjects of the two study groups, serum magnesium levels were estimated at the time of admission (Day 0), Day 1 and Day 2 of hospitalization using an atomic absorption spectrometer.

STATISTICAL ANALYSIS USED

Scandinavian stroke scores were calculated on Day 3, day of discharge and Day 28. Paired t-test was employed for comparison of stroke scores on Day 3, day of discharge and Day 28 within the same group and the unpaired t-test was used for the intergroup comparison, i.e. comparison of stroke scores of control group with corresponding stroke scores of magnesium group.

RESULTS

Comparison of stroke scores on Day 3 and day of discharge, on the day of discharge and Day 28 and on Day 3 and Day 28 in the magnesium group produced a t-value of 5.000 and P <0.001, which was highly significant. However, the comparison of the mean stroke scores between the magnesium and the control groups on Day 3, day of discharge and Day 28 yielded a P-value of >0.05, which was not significant.

CONCLUSIONS

The study failed to document a statistical significant stroke recovery in spite of achieving a significant rise in serum magnesium level, more than that necessary for neuroprotection, with an intravenous magnesium sulfate regime.

Eligibility for Intravenous Recombinant Tissue-Type Plasminogen Activator Within a Population: The Effect of the European Cooperative Acute Stroke Study (ECASS) III Trial

BACKGROUND AND PURPOSE

The publication of the European Cooperative Acute Stroke Study (ECASS III) expanded the treatment time to thrombolysis for acute ischemic stroke from 3 to 4.5 hours from symptom onset. The impact of the expanded time window on treatment rates has not been comprehensively evaluated in a population-based study.

METHODS

All patients with an ischemic stroke presenting to an emergency department during calendar year 2005 in the 17 hospitals that compromise the large 1.3 million Greater Cincinnati/Northern Kentucky population were included in the analysis. Criteria for exclusion from thrombolytic therapy are analyzed retrospectively for both the standard and expanded timeframes with varying door-to-needle times.

RESULTS

During the study period, 1838 ischemic strokes presenting to an emergency department were identified. A small proportion of them arrived in the expanded time window (3.4%) compared with the standard time window (22%). Only 0.5% of those who arrived in this timeframe met eligibility criteria for thrombolysis compared with 5.9% using standard eligibility criteria in the standard timeframe. These results did not vary significantly by repeated analysis varying the door-to-needle time or the expanded time window's exclusion criteria.

CONCLUSIONS

In reality, the expanded time window for thrombolysis in acute ischemic stroke benefits few patients. If we are to improve recombinant tissue-type plasminogen activator administration rates, our focus should be on improving stroke awareness, transport to facilities with ability to administer thrombolysis, and familiarity of physicians with acute stroke treatment guidelines.

Applications of stenting for intracranial atherosclerosis

Intracranial atherosclerosis presents a therapeutic challenge to medical and surgical physicians alike. Despite maximal medical therapy, the stroke rate from this disease is still high, especially when arterial stenosis is severe and patients are symptomatic. Open surgical therapy has yet to be shown to be a more efficacious treatment than medical therapy alone, largely due to the relatively high rates of perioperative complications. Angioplasty has a similar fate, with the risk of periprocedural complications outweighing the overall benefit of treatment. With the advent of stents for use in intracranial vasculature, new hope has arisen for the treatment of intracranial atherosclerosis. The NEUROLINK system, the drug-eluting stents Taxus and Cypher, the flexible Wingspan stent, the Apollo stent, and the Pharos stent have all been used in various prospective and retrospective clinical studies with varying technical and clinical results. The authors' objective is to review and loosely compare the data presented for each of these stenting systems. While the Wingspan stent appears to have somewhat of an advantage with regard to technical success in comparison with the other stenting systems, the clinical follow-up time of its studies is too short to properly compare its complication rates with those of other stents. Before we continue to move forward with stenting for intracranial stenosis, a randomized prospective trial is ultimately needed to directly compare intracranial stenting to medical therapy.

Antihypertensives are administered selectively in emergency department patients with subarachnoid hemorrhage

Elevated blood pressure is common in patients with acute subarachnoid hemorrhage (SAH). American Heart Association guidelines do not specify a blood pressure target, but limited data suggest that systolic blood pressure (SBP)≥160 mmHg is associated with increased risk of rebleeding and neurologic decline. In a population-based study, we determined the frequency of antihypertensive therapy in emergency department (ED) patients with SAH and the proportion of those patients with SBP≥160 mmHg who received this therapy. In 2005, nontraumatic SAH cases were retrospectively ascertained at 16 hospitals in our region by screening for International Classification of Diseases Ninth Revision diagnostic codes 430-436. Blood pressure was recorded at ED presentation and also before and after any treatment with antihypertensives. Hypotension was defined as SBP<100 mmHg. The Mann-Whitney U test and χ2 test were used for comparisons. Our cohort comprised 82 patients with SAH presenting to an ED; 4 patients were excluded. The median age of the included patients was 54 years, 74.4% were female, 29.5% were black, and 31 (39.7%) had SBP≥160 mmHg. Antihypertensive therapy was given to 22 of 31 patients (70.9%) with SBP≥160 mmHg and to 4 of 47 patients (8.5%) with SBP<160 mmHg. No patients became hypotensive after receiving treatment. Age, sex, Glascow Coma Scale score, and National Institutes of Health Stroke Scale score were similar between treated and untreated patients. In the absence of definitive evidence, current blood pressure management in local EDs appears reasonable. Further studies of blood pressure management in acute SAH are warranted.

A computational model of use-dependent motor recovery following a stroke: optimizing corticospinal activations via reinforcement learning can explain residual capacity and other strength recovery dynamics

This paper describes a computational model of use-dependent recovery of movement strength following a stroke. The model frames the problem of strength recovery as that of learning appropriate activations of residual corticospinal neurons to their target motoneuronal pools. For example, for an agonist/antagonist muscle pair, we assume the motor system must learn to activate preserved agonist-exciting corticospinal neurons and deactivate preserved antagonist-exciting corticospinal neurons. The model incorporates a biologically plausible reinforcement learning algorithm for adjusting cell activation patterns-stochastic search-using generated limb force as the teaching signal to adjust the synaptic weights that determine cell activations. The model makes predictions consistent with clinical and brain imaging data, such as that patients can achieve an increase in strength after appearing to reach a recovery plateau (i.e., "residual capacity"), that the differential effect of a dose of movement practice will be greater earlier in recovery, and that force-related brain activation will increase in secondary motor areas following a stroke. An interesting prediction that could be explored clinically is that temporarily inhibiting subpopulations of more powerfully connected corticospinal neurons during late movement training will allow the motor system to optimize corticospinal neurons with a weaker influence, whose optimization was blocked by the rapid optimization of more strongly connected neurons early in training.

Outcome of the 'Drip-and-Ship' Paradigm among Patients with Acute Ischemic Stroke: Results of a Statewide Study

Background

The ‘drip-and-ship’ paradigm denotes a treatment regimen in patients in whom intravenous (IV) recombinant tissue plasminogen activator (rt-PA) is initiated at the emergency department (ED) of a community hospital, followed by transfer within 24 h to a comprehensive stroke center. Although the drip-and-ship paradigm has the potential to increase the number of patients who receive IV rt-PA, comparative outcomes have not been assessed at a population-based level.

Methods

Statewide estimates of thrombolysis, associated in-hospital outcomes, and hospitalization charges were obtained from 2008–2009 Minnesota Hospital Association data for all patients hospitalized with a primary diagnosis of ischemic stroke. Patients who were assigned the drip-and-ship code [International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) V45.88] were classified under the drip-and-ship paradigm. Patients who underwent thrombolysis (ICD-9-CM code 99.10) without drip-and-ship code were classified as primary ED arrival. Patient outcomes were analyzed after stratification into patients treated with IV rt-PA through primary ED arrival or drip-and-ship paradigm.

Results

Of the 21,024 admissions, 602 (2.86%) received IV rt-PA either through primary ED arrival (n = 473) or the drip-and-ship paradigm (n = 129). IV rt-PA was administered in 30 hospitals, of which 13 hospitals used the drip-and-ship paradigm; the number of patients treated with the drip-and-ship paradigm varied from 1 to 40 between the 13 hospitals. The rates of secondary intracerebral or subarachnoid hemorrhage were higher in patients treated with IV rt-PA through primary ED arrival compared with those treated with the drip-and-ship paradigm (8.5 vs. 3.1%, respectively; p = 0.038). The in-hospital mortality rate was similar among ischemic stroke patients receiving IV rt-PA through primary ED arrival or the drip-and-ship paradigm (5.9 vs. 7.0%, respectively). The mean hospital charges were USD 65,669 for primary ED arrival and USD 47,850 for drip-and-ship-treated patients (p < 0.001). The rate of admission to a certified stroke center as final destination for acute hospitalization was higher in patients treated by drip-and-ship paradigm compared with those treated by primary ED arrival mode (p = 0.015).

Conclusions

The results of the drip-and-ship paradigm compare favorably with IV rt-PA treatment through primary ED arrival in this statewide study. Our results support the recommendations of various professional organizations that the drip-and-ship method of IV rt-PA administration for stroke may be an effective option for increasing the utilization of IV rt-PA on a large scale.

A systematic review of validated methods for identifying cerebrovascular accident or transient ischemic attack using administrative data

PURPOSE

To perform a systematic review of the validity of algorithms for identifying cerebrovascular accidents (CVAs) or transient ischemic attacks (TIAs) using administrative and claims data.

METHODS

PubMed and Iowa Drug Information Service searches of the English language literature were performed to identify studies published between 1990 and 2010 that evaluated the validity of algorithms for identifying CVAs (ischemic and hemorrhagic strokes, intracranial hemorrhage, and subarachnoid hemorrhage) and/or TIAs in administrative data. Two study investigators independently reviewed the abstracts and articles to determine relevant studies according to pre-specified criteria.

RESULTS

A total of 35 articles met the criteria for evaluation. Of these, 26 articles provided data to evaluate the validity of stroke, seven reported the validity of TIA, five reported the validity of intracranial bleeds (intracerebral hemorrhage and subarachnoid hemorrhage), and 10 studies reported the validity of algorithms to identify the composite endpoints of stroke/TIA or cerebrovascular disease. Positive predictive values (PPVs) varied depending on the specific outcomes and algorithms evaluated. Specific algorithms to evaluate the presence of stroke and intracranial bleeds were found to have high PPVs (80% or greater). Algorithms to evaluate TIAs in adult populations were generally found to have PPVs of 70% or greater.

CONCLUSIONS

The algorithms and definitions to identify CVAs and TIAs using administrative and claims data differ greatly in the published literature. The choice of the algorithm employed should be determined by the stroke subtype of interest.

Electrical stimulation for the management of aspiration during swallowing

Protection of the airway during swallow is often compromised following stroke and other neurological diseases. If a patient fails to recover airway protection with standard therapy, they are often left with few if any options to avoid repeated pneumonia resulting from aspiration. For them, the only option is no food by mouth and a PEG-tube for nutrition. Functional electrical stimulation offers possible solutions for restoring airway protection. Here we report the capabilities of transtracheal stimulation for vocal fold closure and selective stimulation of the XII cranial nerve to produce elevation of the hyolaryngotracheal complex. These stimulation locations add to our toolbox for managing swallowing difficulties and allow patients to maintain oral feeding.

The practice of carotid revascularization in a large metropolitan population

Carotid endartectomy (CEA) and carotid artery stenting (CAS) reduce the risk of stroke when performed with acceptable perioperative morbidity and mortality. Studies from the 1980s in the greater Cincinnati/northern Kentucky population showed that perioperative risk after CEA exceeded the recommended boundaries of 3.0% for asymptomatic stenosis and 6.0% for symptomatic stenosis. We investigated the indications and outcomes for CEA and CAS in the same population during 2005. We identified all residents of the greater Cincinnati/northern Kentucky region who underwent CEA or CAS at any local hospital during 2005. Identified cases of transient ischemic attack or stroke occurring before or after CEA or CAS were abstracted by study nurses and reviewed by a study physician. The main outcome of interest was 30-day risk of stroke or death after CEA or CAS. Events were analyzed using Kaplan-Meier statistics. Among approximately 1.3 million greater Cincinnati/northern Kentucky residents, 525 CEAs were performed, 343 (65%) for asymptomatic stenosis and 182 (35%) for symptomatic stenosis. There were 43 CAS procedures, 23 (53%) for asymptomatic stenosis and 20 (47%) for symptomatic stenosis. The 30-day perioperative risk of stroke or death after CEA was 3.3% (95% confidence interval [CI], 1.8%-5.9%) for asymptomatic stenosis and 6.3% (95% CI, 3.5%-11.1%) for symptomatic stenosis. The 30-day perioperative risk of stroke or death after CAS was 4.6% (95% CI, 0.7%-28.1%) for asymptomatic stenosis and 21.1% (95% CI, 8.5%-46.8%) for symptomatic stenosis. Point estimates for perioperative risk after CEA were improved from previous studies but remained above the recommended benchmarks. The number of CAS procedures was low, but the perioperative risk was significant.

How often are patients with ischemic stroke eligible for decompressive hemicraniectomy?

BACKGROUND AND PURPOSE

Malignant middle cerebral artery infarction is estimated to occur in 10% of ischemic strokes, but few patients undergo decompressive hemicraniectomy, a proven therapy. We determined the proportion of patients with ischemic stroke without significant baseline disability with large middle cerebral artery infarction who would have been potentially eligible for hemicraniectomy in an era before publication of recent hemicraniectomy trials.

METHODS

Ischemic stroke cases that occurred in 2005 among residents of the 5-county Greater Cincinnati/Northern Kentucky area were ascertained. Two study physicians reviewed all clinical and neuroimaging data for patients with baseline modified Rankin Scale score < 2, age ≥ 18 years with National Institutes of Health Stroke Scale score ≥ 10. Large middle cerebral artery infarction was defined as >50% of the middle cerebral artery territory or >145 mL on diffusion-weighted MRI. Other eligibility criteria for hemicraniectomy, based on the pooled analysis of recent clinical trials, were age 18 to 60 years and National Institutes of Health Stroke Scale score > 15.

RESULTS

Of 2227 ischemic strokes, 39 (1.8%) with baseline modified Rankin Scale score < 2 had large middle cerebral artery infarction. None underwent hemicraniectomy, and 16 (41.0%) died within 30 days. Six patients (0.3% of all ischemic strokes) were potentially eligible for hemicraniectomy; 1 died within 30 days.

CONCLUSIONS

Based on criteria from clinical trials, only 0.3% of cases were eligible for hemicraniectomy. Given the survival and functional outcome benefit in treated patients, future studies should determine whether additional subgroups of patients with ischemic stroke may benefit from hemicraniectomy.