The NIHSS supplementary motor scale: a valid tool for multidisciplinary recovery trials

BACKGROUND

There is a growing interest in therapies that may augment motor recovery that could be initiated in the acute stroke unit and maintained through the rehabilitation period. Homogenization of the currently fragmented stroke clinicometrics is necessary before such multidisciplinary trials can be conducted. The supplementary motor scale of the NIH Stroke Scale (SMS-NIHSS) is a simple and reliable scale for assessing proximal and distal motor function in the upper and lower extremities. We hypothesized that the currently underutilized SMS-NIHSS is a valid tool for assessing motor recovery with prognosticative value.

METHODS

We performed an analysis of SMS-NIHSS scores recorded in 1,281 patients enrolled in the Trial of ORG 10172 in Acute Stroke Treatment (TOAST). We plotted the probability of a favorable outcome (FO) and very favorable outcome (VFO) at 3 months based on the baseline SMS-NIHSS scores. In order to better study the relationship between SMS-NIHSS and 3-month functional outcome, we performed multivariate logistic regression analyses using both FO and VFO as outcome measures. Analyses were adjusted for potential confounders such as age, sex, side of the lesion, time from symptom onset to emergency room arrival, temperature, systolic blood pressure, blood glucose level and treatment group assignment (ORG 10172 vs. placebo). We also calculated the Spearman correlation coefficient between the SMS-NIHSS, Barthel Index (BI) and Glasgow Outcome Score (GOS) obtained at the 3-month visit.

RESULTS

The mean SMS-NIHSS scores were 8.18 at baseline and 4.68 at 3 months. The SMS-NIHSS scores showed a gradual improvement during the first 3 months after stroke. There was a linear relationship between the baseline SMS-NIHSS scores and the probability of an FO or VFO at 3 months. The SMS-NIHSS baseline score was an independent predictor of FO (OR = 0.86; 95% CI 0.84-0.87; p < 0.0001) and VFO (OR = 0.85; 95% CI 0.84-0.87; p < 0.0001) at 3 months after adjusting for confounders. The degree of improvement in the SMS-NIHSS scores from baseline to 3 months was also independently associated with FO and VFO (p < 0.0001). At 3 months, SMS-NIHSS scores showed a strong correlation with the BI (r = -0.70; p < 0.0001) and GOS (r = 0.73; p < 0.0001).

CONCLUSIONS

The SMS-NIHSS is a valid scale for assessing motor recovery with prognosticative value, and may be sensitive to changes during recovery. Given that the SMS-NIHSS is an extension of the widely accepted NIHSS, it could be easily implemented in trials conducted in a variety of clinical research settings, including acute stroke hospitals and rehabilitation units.

Investigating the mechanisms of perioperative ischemic stroke in the Carotid Occlusion Surgery Study

OBJECT

The Carotid Occlusion Surgery Study (COSS) was a large, prospective clinical trial that examined whether superficial temporal artery-middle cerebral artery (STA-MCA) bypass, in addition to best medical therapy, reduced the risk of ipsilateral ischemic stroke in patients with carotid artery occlusion and hemodynamic cerebral ischemia. Despite improved cerebral hemodynamics and excellent bypass graft patency rates, COSS failed to show a benefit for the surgical group with respect to ipsilateral stroke recurrence at 2 years after treatment. This was due to a lower than expected rate of recurrent ipsilateral stroke in the medically treated group and a high rate of perioperative ipsilateral strokes in the surgical group. Critics of the trial have cited surgeon inexperience and technical difficulties related to the performance of the bypass graft as a leading cause of failure of the trial.

METHODS

The authors retrospectively identified all patients from the COSS with an ipsilateral, perioperative (< 30 days) ischemic stroke after STA-MCA cortical branch anastomosis. Study records, operative notes, stroke adjudication forms, and imaging studies were reviewed. Ischemic strokes were characterized as bypass graft related or non-bypass graft related based on clinical and radiographic findings.

RESULTS

Fourteen of 93 surgically treated patients experienced an ipsilateral, perioperative ischemic stroke. Postoperatively, the mean oxygen extraction fraction (OEF) ratio between the symptomatic and asymptomatic cerebral hemisphere significantly improved in these patients (1.30 ± 0.18 preoperative vs 1.12 ± 0.11 postoperative; p = 0.02), but did not normalize. In this cohort, total MCA occlusion time during the anastomosis (54.3 ± 23.5 minutes) was no different from the MCA occlusion time in those surgical patients who did not have a perioperative stroke (45.4 ± 24.2 minutes, p = 0.2). Bypass graft patency rates in patients with a perioperative stroke were 92% at 30 days (11 of 12 patients with patency data) and 83% at last follow-up visit (10 of 12 patients with patency data). These patency rates were not significantly different from those achieved at 30 days (100%; 76 of 76 patients with patency data; p = 0.14) and at last follow-up (99%; 71 of 72 patients with patency data; p = 0.052) in patients without a perioperative stroke. Eighty-six percent (12 of 14 patients) of strokes were likely attributable to factors unrelated to the STA-MCA anastomosis. Only 21% of strokes (3 of 14 patients) were in the territory of the recipient vessel and likely related to technical performance of the anastomosis itself. One patient was thought to have dual stroke mechanisms.

CONCLUSIONS

Only a small minority of ipsilateral, perioperative ischemic strokes in the COSS could be attributed to technical problems of the bypass anastomosis. The majority of ischemic strokes could not be ascribed to this cause and were most likely due to patient hemodynamic fragility and the inability of patients to tolerate surgery.

Management of patients with stroke: is it time to expand treatment options?

Approximately 700,000 people in the United States have an ischemic stroke annually. Substantial research has tested therapies for the very early treatment of ischemic stroke but, to date, only intravenous thrombolysis and intra-arterial measures to restore perfusion have shown success. Despite a 15-year effort to increase the use of these therapies, only approximately 5% of patients with stroke are currently being treated. Although most patients with stroke have some neurological recovery, more than half of stroke survivors have residual impairments that lead to disability or long-term institutionalized care. Laboratory research has demonstrated several mechanisms that help the brain to recover after a stroke. New pharmacological and cell-based approaches that are known to promote brain plasticity are emerging from laboratory studies and may soon expand the window for stroke treatment to restore function. It is time to build on this knowledge and to translate the understanding of recovery after stroke into the clinical setting. Measures that might augment recovery should become a major focus of clinical research in stroke in the 21st century.

Targeted use of heparin, heparinoids, or low-molecular-weight heparin to improve outcome after acute ischaemic stroke: an individual patient data meta-analysis of randomised controlled trials

Background

Many international guidelines on the prevention of venous thromboembolism recommend targeting heparin treatment at patients with stroke who have a high risk of venous thrombotic events or a low risk of haemorrhagic events. We sought to identify reliable methods to target anticoagulant treatment and so improve the chance of avoiding death or dependence after stroke.

Methods

We obtained individual patient data from the five largest randomised controlled trials in acute ischaemic stroke that compared heparins (unfractionated heparin, heparinoids, or low-molecular-weight heparin) with aspirin or placebo. We developed and evaluated statistical models for the prediction of thrombotic events (myocardial infarction, stroke, deep vein thrombosis, or pulmonary embolism) and haemorrhagic events (symptomatic intracranial or significant extracranial) in the first 14 days after stroke. We calculated the absolute risk difference for the outcome “dead or dependent” in patients grouped by quartiles of predicted risk of thrombotic and haemorrhagic events with random effect meta-analysis.

Findings

Patients with ischaemic stroke who were of advanced age, had increased neurological impairment, or had atrial fibrillation had a high risk of both thrombotic and haemorrhagic events after stroke. Additionally, patients with CT-visible evidence of recent cerebral ischaemia were at increased risk of thrombotic events. In evaluation datasets, the area under a receiver operating curve for prediction models for thrombotic events was 0·63 (95% CI 0·59–0·67) and for haemorrhagic events was 0·60 (0·55–0·64). We found no evidence that the net benefit from heparins increased with either increasing risk of thrombotic events or decreasing risk of haemorrhagic events.

Interpretation

There was no evidence that patients with ischaemic stroke who were at higher risk of thrombotic events or lower risk of haemorrhagic events benefited from heparins. We were therefore unable to define a targeted approach to select the patients who would benefit from treatment with early anticoagulant therapy. We recommend that guidelines for routine or selective use of heparin in stroke should be revised.

Funding

MRC.

Abstract 155: No Increased Stroke Risk with Lower Blood Pressures in Hemodynamic Cerebral Ischemia

Patients with symptomatic carotid artery occlusion and hemodynamic cerebral ischemia manifested by increased oxygen extraction fraction (OEF) are at 20-25% risk for ipsilateral stroke within 2 years. Disagreement exists whether strict blood pressure control is the best medical management for these patients or if higher blood pressures are needed to preserve cerebral perfusion. To address this issue, we analyzed data from the non-surgical group of the Carotid Occlusion Surgery Study (COSS), a randomized, controlled trial performed to determine whether EC-IC bypass could reduce subsequent ipsilateral ischemic stroke at two years in participants with recently symptomatic internal carotid artery occlusion and increased OEF. Of the 98 patients in the non-surgical group, 95 had 1-19 blood pressures recorded at follow-up visits. Average systolic and diastolic blood pressures were calculated from these data. Cox regression analyses were used to estimate the relative hazard of a post-randomization ipsilateral stroke in the tercile of subjects with the lowest average blood pressures ( </= 124 mm Hg systolic or 73 mm Hg diastolic) compared to the remainder. Lower blood pressures were associated with reduced, not increased, stroke risk. If the samples analyzed were from populations in which the true hazards were the same, hazard ratios of this magnitude or less would be expected less than 10% of the time. We cannot conclude from these data that strict blood pressure control is beneficial in patients with symptomatic carotid occlusion and increased OEF. However, since we found no evidence that that blood pressures below 124/73 were associated with increased stroke risk, we recommend treatment of blood pressure in these patients according to JNC VII guidelines to targets of < 140/90 or <130/80 for those with concomitant diabetes mellitus or kidney disease.

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

BACKGROUND AND PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

The types of neurological deficits might not justify withholding treatment in patients with low total National Institutes of Health Stroke Scale scores

BACKGROUND AND PURPOSE

There is controversy regarding the threshold for treating patients with mild strokes. Physicians often withhold acute treatment in these patients if they perceive the symptoms are not going to be disabling. We tested the appropriateness of this practice by analyzing the relationship between specific neurological deficits in the National Institutes of Health Stroke Scale (NIHSS) score and long-term outcome among patients with a low total NIHSS score.

METHODS

We performed a secondary analysis on those patients enrolled in the Trial of ORG 10172 in Acute Stroke Treatment that presented within 4.5 hours of symptom onset and had a baseline NIHSS score ≤6 (n=194). We performed multivariate logistic regression analyses using very favorable outcome at 3 months as the outcome variable and each of the individual items of the baseline NIHSS examination and syndromic combinations of NIHSS scores as predictors. The analyses were adjusted for potential confounders with and without adjusting for total NIHSS score.

RESULTS

Baseline total NIHSS scores were inversely associated with very favorable outcome at 3 months. No individual NIHSS item, or syndromic combination of NIHSS scores, was independently associated with very favorable outcome in a consistent manner after accounting for confounders and collinearity.

CONCLUSIONS

The types of neurological deficits in the baseline NIHSS are not independent predictors of long-term prognosis for patients with mild stroke. These exploratory findings argue against the practice of withholding reperfusion treatment in patients with mild stroke when the types of baseline NIHSS deficits are perceived to be nondisabling.

Cerebral hemodynamics and cognitive impairment: baseline data from the RECON trial

OBJECTIVE

To determine whether unihemispheral hemodynamic failure is independently associated with cognitive impairment among participants in the National Institute of Neurological Disorders and Stroke-sponsored, multicenter, randomized clinical trial, Randomized Evaluation of Carotid Occlusion and Neurocognition (RECON).

METHODS

Forty-three patients were randomized into RECON after recent symptomatic carotid artery occlusion and asymmetrically increased oxygen extraction fraction (OEF) by PET (OEF ratio >1.13), indicating stage II hemodynamic failure on the side of occlusion. The PET-positive patients were compared with 28 RECON-enrolled patients who met all clinical and radiographic inclusion/exclusion criteria but had no OEF asymmetry. A multivariable regression compared patients with PET OEF >1.13 or ≤1.13, stratifying by TIA vs. stroke as the qualifying event. The dependent variable was a composite neurocognitive score derived from averaging age-normalized z scores on a test battery that included global and internal carotid artery (ICA) side-relevant hemisphere-specific tests.

RESULTS

There were no differences in demographic, clinical, or radiologic characteristics between the PET-positive and PET-negative patients except for PET OEF asymmetry. The unadjusted average neurocognitive z score was -1.45 for the PET-positive and -1.25 for the PET-negative patients, indicating cognitive impairment in both groups but no difference between them (p = 0.641). After adjustment for age, education, side of occlusion, depression, and previous stroke, there was a significant difference between PET-positive and PET-negative patients among those with TIA as a qualifying event (average z score = -1.41 vs. -0.76, p = 0.040). Older age and right ICA side were also significant in this model.

CONCLUSION

Hemodynamic failure is independently associated with cognitive impairment in patients with carotid occlusion. This finding establishes the physiologic parameter upon which the extracranial-intracranial bypass will be tested.

Extracranial-intracranial bypass surgery for stroke prevention in hemodynamic cerebral ischemia: the Carotid Occlusion Surgery Study randomized trial

CONTEXT

Patients with symptomatic atherosclerotic internal carotid artery occlusion (AICAO) and hemodynamic cerebral ischemia are at high risk for subsequent stroke when treated medically.

OBJECTIVE

To test the hypothesis that extracranial-intracranial (EC-IC) bypass surgery, added to best medical therapy, reduces subsequent ipsilateral ischemic stroke in patients with recently symptomatic AICAO and hemodynamic cerebral ischemia.

DESIGN

Parallel-group, randomized, open-label, blinded-adjudication clinical treatment trial conducted from 2002 to 2010.

SETTING

Forty-nine clinical centers and 18 positron emission tomography (PET) centers in the United States and Canada. The majority were academic medical centers.

PARTICIPANTS

Patients with arteriographically confirmed AICAO causing hemispheric symptoms within 120 days and hemodynamic cerebral ischemia identified by ipsilateral increased oxygen extraction fraction measured by PET. Of 195 patients who were randomized, 97 were randomized to receive surgery and 98 to no surgery. Follow-up for the primary end point until occurrence, 2 years, or termination of trial was 99% complete. No participant withdrew because of adverse events.

INTERVENTIONS

Anastomosis of superficial temporal artery branch to a middle cerebral artery cortical branch for the surgical group. Antithrombotic therapy and risk factor intervention were recommended for all participants.

MAIN OUTCOME MEASURE

For all participants who were assigned to surgery and received surgery, the combination of (1) all stroke and death from surgery through 30 days after surgery and (2) ipsilateral ischemic stroke within 2 years of randomization. For the nonsurgical group and participants assigned to surgery who did not receive surgery, the combination of (1) all stroke and death from randomization to randomization plus 30 days and (2) ipsilateral ischemic stroke within 2 years of randomization.

RESULTS

The trial was terminated early for futility. Two-year rates for the primary end point were 21.0% (95% CI, 12.8% to 29.2%; 20 events) for the surgical group and 22.7% (95% CI, 13.9% to 31.6%; 20 events) for the nonsurgical group (P = .78, Z test), a difference of 1.7% (95% CI, -10.4% to 13.8%). Thirty-day rates for ipsilateral ischemic stroke were 14.4% (14/97) in the surgical group and 2.0% (2/98) in the nonsurgical group, a difference of 12.4% (95% CI, 4.9% to 19.9%).

CONCLUSION

Among participants with recently symptomatic AICAO and hemodynamic cerebral ischemia, EC-IC bypass surgery plus medical therapy compared with medical therapy alone did not reduce the risk of recurrent ipsilateral ischemic stroke at 2 years.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00029146.

Aspirin treatment failure and the risk of recurrent stroke and death among patients with ischemic stroke

BACKGROUND

The prognostic value of occurrence of ischemic stroke in a patient despite aspirin treatment (aspirin treatment failure) is not known. Our objective was to determine if aspirin treatment failure predicts recurrent ischemic stroke and/or death.

METHODS

We performed a post-hoc analysis of data from the National Institute of Neurological Disorders and Stroke (NINDS) intravenous recombinant tissue plasminogen activator (rt-PA) trial and the Trial of ORG 10172 in Acute Stroke Treatment (TOAST). Multivariate analysis was used to calculate the odds ratio (OR) of recurrent stroke and recurrent stroke or death for aspirin treatment failure patients for the duration of available follow-up (3 months for TOAST patients; 12 months for NINDS rt-PA trial patients).

RESULTS

The rate of aspirin treatment failure was 40% and 35% among 1275 patients and 624 patients recruited in the TOAST and NINDS rt-PA trials, respectively. The risk of stroke and death at 3 months and 1 year was not higher among patients classified as aspirin treatment failures among the TOAST (OR 1.1; 95% confidence interval [CI] 0.8-1.6; P = .7) or NINDS rt-PA trial patients (OR 0.8; 95% CI 0.6-1.3; P = .4), respectively. In subgroup analysis, aspirin treatment failure was not found to be associated with recurrent stroke or with the combined endpoint of stroke and death among categories defined by etiologic subtype, including those with large artery atherosclerosis.

CONCLUSIONS

In a post-hoc analysis of 2 randomized ischemic stroke trials, aspirin treatment failure was not found to be associated with an increased risk of recurrent stroke or death.

Delayed catastrophic intracerebral hemorrhage preceded by progressive recovery after carotid stenting for acute ischemic stroke

BACKGROUND

Hemorrhagic transformation (HT) is a feared complication of reperfusion therapy for treatment of acute ischemic stroke. Generally, HT occurs within 24-36 hours after thrombolysis.

SUMMARY OF CASE

We present a case of a fatal symptomatic HT of an infarction that occurred 7 days after acute ischemic stroke which was preceded by a remarkable recovery following a combination of acute revascularization therapies.

CONCLUSION

Fatal symptomatic HT is a rare potential complication that can occur after several days of treatment of acute ischemic stroke.

Management of acute stroke: impact of registration studies

Stroke is a life-threatening or life-changing disease that is expensive in health care costs and lost productivity. Stroke also is a leading cause of human suffering. While the risk of stroke may be reduced with advances in prevention, recent advances in acute care can limit the consequences of stroke. In particular, the success of reperfusion therapies including intra-arterial interventions and intravenous administration of thrombolytic agents means that some patients with stroke may be cured. Still, the time window for effective treatment of stroke is relatively short. As a result, modern stroke management requires the close collaboration of the public, health care providers, administrators, insurance companies, and the government. Potential strategies to extend modern stroke care to as many patients as possible include 1) educational programs to train community emergency medical service personnel and physicians, 2) development of stroke care plans at community hospitals, 3) an integrated community-comprehensive stroke center program based on consultation, and telemedicine. The goal is to have a highly integrated approach to provide emergency treatment of the stroke that provides key emergency treatment, including intravenous administration of thrombolytic medications, at a community hospital (primary stroke center) with evacuation to a comprehensive stroke center that has resources and expertise that are not available in the primary stroke center. Taiwan is an ideal location for the development of such regional stroke programs.

Lack of international consensus on ethical aspects of acute stroke trials

Acute stroke trials are becoming increasingly multinational. Working toward a shared ethical standard for acute stroke research necessitates evaluating the degree of consensus among international researchers. We surveyed all 275 coinvestigators and coordinators who participated in the AbESTT II study (evaluating abciximab vs placebo) about their experience with their local institutional review board (IRB) or equivalent, as well as, about their personal beliefs regarding the ethical aspects of acute stroke trials. A total of 90 coinvestigators from 15 different countries responded to our survey. Among the IRBs represented by the responding coinvestigators, only 18% allowed surrogate consent to be obtained over the phone. Although 52% allowed the participation of subjects with aphasia, only 5% allowed the participation of subjects with neglect/hemi-inattention. The National Institutes of Health Stroke Scale score was deemed adequate to establish decisional capacity based on language by 62% of the coinvestigators and 36% of the IRBs. A belief that IRB regulations cause unnecessary delays and fear in relatives/patients was reported by 67% of coinvestigators, and the belief that granting an exemption from informed consent under specific circumstances is appropriate was reported by 41%. There appears to be considerable international diversity in the ethical priorities and informed consent standards among different IRBs and investigators in stroke research. The stroke community should make an attempt to standardize the consent process used in research. Given the critical nature of the time to treatment in stroke care, these standards should be integrated into current frameworks of clinical care and research. The absence of an ethical consensus can become a barrier to advancing stroke treatment internationally.