Scandinavian Neurological Stroke Scale Research Articles

Early Recovery and Functional Outcome are Related with Causal Stroke Subtype: Data from the Tinzaparin in Acute Ischemic Stroke Trial

Baseline severity and causal subtype are predictors of outcome in ischemic stroke. We used data from the Tinzaparin in Acute Ischemic Stroke Trial (TAIST) to further assess the relationship among stroke subtype, early recovery, and outcome. Patients with ischemic stroke (<48 hours ictus) and enrolled into TAIST were included. Severity was measured prospectively as the Scandinavian Neurological Stroke Scale (SNSS) at days 0, 4, 7, and 10. Causal subtype as large artery atherosclerosis (LAA), cardioembolism (CE), or small vessel occlusion (SVO) was assigned after standard investigations. The rate of recovery was calculated as the change in SNSS at each time point. Functional outcome was assessed using the modified Rankin Scale (mRS) and Barthel Index at day 90. Analyses were performed on the 1190 patients in TAIST who met criteria for LAA, CE, and SVO. The largest change in SNSS score occurred between baseline and day 4 and was greatest in SVO (median improvement 4 U), compared with LAA (median improvement 2 U) and CE (median improvement 2 U) (P < .0001). If no improvement in SNSS had occurred by day 4, irrespective of subgroup, then early recovery (median SNSS improvement by day 10: 2) and functional outcome (mRS 4) tended to be limited; patients who recovered early tended to continue to improve (median SNSS improvement by day 10: 11) and had a better outcome at day 90 (median, mRS 2). Recovery is related to causal subtype. In all subtypes most recovery occurred by day 4, and was predictive of longer-term functional outcome.

Stroke severity, early recovery and outcome are each related with clinical classification of stroke: Data from the ‘Tinzaparin in Acute Ischaemic Stroke Trial’ (TAIST)

Introduction Baseline severity and clinical stroke syndrome (Oxford Community Stroke Project, OCSP) classification are predictors of outcome in stroke. We used data from the ‘Tinzaparin in Acute Ischaemic Stroke Trial’ (TAIST) to assess the relationship between stroke severity, early recovery, outcome and OCSP syndrome. Methods TAIST was a randomised controlled trial assessing the safety and efficacy of tinzaparin versus aspirin in 1484 patients with acute ischaemic stroke. Severity was measured as the Scandinavian Neurological Stroke Scale (SNSS) at baseline and days 4, 7 and 10, and baseline OCSP clinical classification recorded: total anterior circulation infarct (TACI), partial anterior circulation infarct (PACI), lacunar infarct (LACI) and posterior circulation infarction (POCI). Recovery was calculated as change in SNSS from baseline at day 4 and 10. The relationship between stroke syndrome and SNSS at days 4 and 10, and outcome (modified Rankin Scale at 90 days) were assessed. Results Stroke severity was significantly different between TACI (most severe) and LACI (mildest) at all four time points ( p < 0.001), with no difference between PACI and POCI. The largest change in SNSS score occurred between baseline and day 4; improvement was least in TACI (median 2 units), compared to other groups (median 3 units) ( p < 0.001). If SNSS did not improve by day 4, then early recovery and late functional outcome tended to be limited irrespective of clinical syndrome (SNSS, baseline: 31, day 10: 32; mRS, day 90: 4); patients who recovered early tended to continue to improve and had better functional outcome irrespective of syndrome (SNSS, baseline: 35, day 10: 50; mRS, day 90: 2). Conclusions Although functional outcome is related to baseline clinical syndrome (best with LACI, worst with TACI), patients who improve early have a more favourable functional outcome, irrespective of their OCSP syndrome. Hence, patients with a TACI syndrome may still achieve a reasonable outcome if early recovery occurs.

Early stroke: a dynamic process.

In the acutely infarcted brain, cytokines are released into cerebrospinal fluid and blood. Interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, among others, may play a role in the acute increases in plasma adrenocorticotropic hormone, cortisol, epinephrine, norepinephrine, and vasopressin.1–6 Increases in cytokines and hormones may in turn induce changes in other variables. When recorded on admission in acute stroke patients, many variables have been found to be associated with poor outcome in acute stroke. Body temperature7 is one such variable, blood glucose another,8–18 and C-reactive protein (CRP)19–22 and white blood cell count (WBC)20,23 serum cortisol and ferritin24 are further examples. Elevated plasma and cerebrospinal fluid levels of glutamate, glycine,25 ferritin,26 and IL-627 were also associated with deteriorating stroke. It seems plausible that these variables generally are unaffected at stroke onset and then increase in the early hours after onset, depending on the severity of the stroke. We found this to be the case with temperature,28 which in a large series of patients was normal when measured within 2 hours of stroke onset, but which rose at 4 to 6 hours after stroke onset in patients with severe neurological deficits. At 8 to 10 hours after stroke onset, elevated temperature was associated with poor outcome. This association arose several hours after onset of severe stroke. Thus, the initial severity of the stroke …

Neurological deterioration in acute ischemic stroke: potential predictors and associated factors in the European cooperative acute stroke study (ECASS) I.

The present study was undertaken to identify potential predictors of and factors associated with early and late progression in acute stroke. We performed secondary analysis of the clinical, biochemical, and radiological data recorded in the acute phase of stroke patients enrolled in the European Cooperative Acute Stroke Study (ECASS) I. Early progressing stroke (EPS) was diagnosed when there was a decrease of > or = 2 points in consciousness or motor power or a decrease of > or = 3 points in speech scores in the Scandinavian Neurological Stroke Scale from baseline to the 24-hour evaluation, and late progressing stroke (LPS) was diagnosed when 1 of these decreases occurred between the 24-hour evaluation and the evaluation at day 7. Using logistic regression analyses, we looked for baseline variables that predicted EPS and LPS and for factors measured after the early or late acute phase and associated with the 2 clinical courses. Of the 615 patients studied, 231 (37.5%) worsened during the first 24 hours after inclusion. The overall incidence of EPS was 37% in the placebo group and 38% in the recombinant tissue plasminogen activator group (P=0.68, Fisher's Exact Test). Focal hypodensity (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3 to 2.9) and hyperdensity of the middle cerebral artery sign (OR, 1.8; 95% CI, 1.1 to 3.1) on baseline computed tomography, longer delay until treatment (OR, 1.2; 95% CI, 1.1 to 1. 4) and history of coronary heart disease (OR, 1.7; 95% CI, 1.1 to 2. 8) and diabetes (OR, 1.8; 95% CI, 1.0 to 3.1) were independent prognostic factors for EPS. Extent of hypodensity >33% in the middle cerebral artery territory (OR, 2.5; 95% CI, 1.6 to 4.0) and brain swelling (OR, 1.8; 95% CI, 1.1 to 3.2) on CT at 24 hours but not hemorrhagic transformation of cerebral infarct nor decrease in systolic blood pressure within the first 24 hours after treatment were associated with EPS in multivariate analyses. LPS was observed in 20.3% of patients. Older age, a low neurological score, and brain swelling at admission independently predicted late worsening. In the setting of a multicenter trial, EPS and LPS are mainly related to computed tomographic signs of cerebral edema. Treatment with recombinant tissue plasminogen activator, hemorrhagic transformation, and moderate changes in systolic blood pressure did not influence the early clinical course.

Acute stroke: prognosis and a prediction of the effect of medical treatment on outcome and health care utilization. The Copenhagen Stroke Study.

Medical treatment of acute stroke with tissue plasminogen activator (tPA) was recently approved in the United States, and neuroprotective agents are being developed. Should all patients with stroke, regardless of severity, receive such treatment? In the Copenhagen Stroke Study we studied the prognosis of stroke in 1,351 unselected patients from a well-defined catchment area treated in a community-based stroke unit from the time of acute admission to death or the end of rehabilitation. Outcome measures were mortality, discharge rates to the patients' own home or to a nursing home, length of hospital stay, and neurological and functional outcomes. Prognosis was stratified according to initial stroke severity measured by the Scandinavian Neurological Stroke Scale (SSS) on admission. We estimated the effect of medical treatment on prognosis and health care utilization by assuming a medically induced decrease in initial stroke severity by 5 and 10 points in the initial SSS score. This mild and moderate decrease in initial stroke severity corresponded to an overall improvement in outcome and an overall cost reduction through shorter hospital stays. This was also true in patients with both mild and moderate stroke. However, in patients with severe stroke, survival increases expenses because of an increased discharge rate to a nursing home and an increase in the cost of acute care and rehabilitation. Future medical stroke trials should therefore focus on the effect and cost of treatment, especially in patients with severe stroke, and search for factors predictive of good clinical outcome in this group.

Comprehensive assessment of activities of daily living in stroke. The Copenhagen stroke study

Objective: To assess activities of daily living (ADL) in stroke in a comprehensive way. The Barthel Index (BI) is widely used in stroke research, but is limited because it measures basic ADL functions only. This study sought to determine whether the Frenchay Activities Index (FAI) is a good choice for supplementary assessment of higher order ADL functions. Design: Prospective and consecutive. Setting: Follow-up investigation 6 months after stroke of patients who were admitted to, and completed rehabilitation at, a stroke unit. Patients: 437 patients with strokes. Main Outcome Measures: Factor analysis of the BI, FAI, and the Scandinavian Neurological Stroke Scale (SSS); distribution characteristics of a comprehensive, combined ADL scale. Results: Five factors were found. One factor comprised all items from the BI and all the motor items from the SSS, but no items from the FAI. The FAI loaded on three other factors. Finally, orientation and speech from the SSS loaded on a separate factor. A combined score consisting of the BI total score and a simple transformation of the FAI total score had a much improved distribution without strong ceiling or floor effects. Conclusions: The FAI supplements the BI with minimal overlap in content. A combined total score has a distribution that makes it very usable for research in stroke outcome and stroke rehabilitation effect.

Acute stroke with atrial fibrillation. The Copenhagen Stroke Study.

Atrial fibrillation (AF) is a common arrhythmia and a major risk factor for stroke. Many physicians remain reluctant to provide stroke prevention by anticoagulant therapy especially for elderly individuals with AF. Using multivariate regression analyses, we studied the characteristics and the prognosis of stroke in patients with AF. The study is part of the Copenhagen Stroke Study, a prospective, community-based study of 1197 patients with acute stroke treated on a stroke unit from the time of acute admission to the end of rehabilitation. Initial stroke severity was measured by the Scandinavian Neurological Stroke Scale (SSS). Neurological and functional outcomes were evaluated by the SSS and the Barthel Index. AF was diagnosed in 18% of the patients. AF increased steeply with age in the stroke population, from 2% in patients < 50 years old, 15% in patients in their 70s, and 28% in patients in their 80s, to 40% in patients > or = 90 years of age. In a multivariate analysis AF was associated with age (odds ratio [OR], 2.0 per 10-year increase; 95% confidence ratio [CI], 1.6 to 2.6), ischemic heart disease (OR, 3.4; 95% CI, 2.4 to 4.8), previous stroke (OR, 1.8; 95% CI, 1.2 to 2.6), and systolic blood pressure (OR, 0.93 per 10-mm Hg increases; 95% CI, 0.88 to 0.99), but not with sex, diabetes, hypertension, previous transient ischemic attack, or silent infarction on computed tomography. Patients with AF had a higher mortality rate (OR, 1.7; 95% CI, 1.2 to 2.5), longer hospital stays (50 days versus 40 days, P < .001), and a lower discharge rate to their own homes (OR, 0.60; 95% CI, 0.44 to 0.85). Neurological and functional outcomes were markedly poorer in patients with AF. Poorer outcome was exclusively explained by initially more-severe strokes. Stroke in patients with AF is generally more severe and outcome markedly poorer than in patients with sinus rhythm. This accentuates the importance of anticoagulant treatment of individuals with AF. A lower blood pressure in the acute stage of stroke may contribute to the increased stroke severity in patients with AF.

Factors delaying hospital admission in acute stroke: the Copenhagen Stroke Study.

Medical treatment of stroke is dependent on a narrow therapeutic time window. We prospectively analyzed the influence of demographic, medical, and pathophysiologic factors on admission delay in 1,197 unselected, acute stroke patients. Twenty five percent were admitted within 3 1/2 hours, 35% within 6 hours, 50% within 14 hours, and 68% within 24 hours after stroke onset. Living alone (odds ratio [OR] 1.75, 95% CI 1.3 to 2.3) and retired working status (OR 1.61, 95% CI 1.01 to 2.54) delayed admission. A well-working social network thus seems important to early admission. The milder the stroke, the higher was the risk of delayed admission (OR 1.25 per 10 points decrease in stroke severity [Scandinavian Neurological Stroke Scale score on admission], 95% CI 1.14 to 1.36). A history of TIA increased the relative chance of early admission by odds 1.64 (95% CI 1.06 to 2.54). Other factors such as age, sex, diabetes, hypertension, ischemic heart disease, other comorbidity, previous stroke, headache, aphasia, apraxia, anosognosia, neglect, lowered consciousness, mental status (Mini-Mental State Examination) and type of stroke (hemorrhage/infarct) had no independent influence on admission time. Admission was markedly delayed in most patients. This represents a major barrier to medical treatment. Patients with the most severe strokes are admitted early, but patients with milder symptoms should also be encouraged to seek immediate admission. The observation that a history of TIA reduced admission time indicates that an increase in public awareness and knowledge may reduce delay and save precious time.

Frequency, Determinants, and Consequences of Anosognosia in Acute Stroke

Anosognosia is a well-known symptom after stroke but its frequency following acute stroke is not known and knowledge of its impact on functional outcome is limited. This prospective study included 566 consecutive, unselected, acute stroke patients. Anoso gnosia was evaluated on acute admission using the test of Bisiach et al. (1986), stroke severity with the Scandinavian Neurological Stroke Scale (SNSS), and activities of daily living (ADLs) with the Barthel Index (BI). Multiple linear and logistic regres sion analyses were done to find the influence of anosognosia on the outcome of stroke per se. The frequency of anosognosia was 21% on acute admission. The lesion was located in the right hemisphere in 81% of the patients. Anosognosia was seen more frequently following cortical vs. subcortical lesions but showed no significant rela tionship to any of the four cortical lobes. The presence of anosognosia per se predicted 11.5 points less in discharge BI, increased the likelihood of death during the hospital stay by a factor of 4.4, and reduced the likelihood of discharge to independent living in survivors by 0.43. Anosognosia is common in acute stroke, has a profound influence on the prognosis, and indicates patients needing special encouragement and assistance with mobilization.

Unified Neurological Stroke Scale Is Valid in Ischemic and Hemorrhagic Stroke

The growing interest in testing new therapeutic agents for acute brain injury has lead to increased use of stroke scales. The reliability and validity of these measures need to be examined more completely. We used structural equation modeling, a technique that merges the analytic procedures of factor analysis and multiple regression, to examine the reliability and construct validity of the Middle Cerebral Artery Neurological Scale and the Scandinavian Neurological Stroke Scale used together as the Unified Neurological Stroke Scale. We also analyzed the predictive validity, sensitivity, and specificity of the scales in predicting mortality and functional outcome. We prospectively studied 84 consecutive patients admitted to a neurology/neurosurgery intensive care unit with intracerebral hemorrhage (n = 30), subarachnoid hemorrhage (n = 15), ischemic stroke (n = 15), and traumatic brain injury (n = 24). Patients were evaluated within 24 hours of admission and at 48-hour intervals until intensive care unit discharge. A total of 386 assessments were obtained. The Functional Independence Measure was administered by telephone 3 months after hospital discharge. High levels of reliability and construct validity were observed for the majority of the Unified Stroke Scale items. Facial palsy and eye movement items had the lowest reliability and validity. Both the Middle Cerebral Artery and Scandinavian Scales were significant predictors of outcome. Sensitivity and specificity varied by diagnosis. Predictive validity of functional outcome was best in groups with ischemic and hemorrhagic stroke rather than traumatic brain injury and subarachnoid hemorrhage. The Unified Stroke Scale demonstrates reliability and construct and predictive validity, and its use is supported in ischemic and hemorrhagic stroke. Structural equation modeling is an appropriate technique for use with scales of this type.

Outcome and time course of recovery in stroke. Part I: Outcome. The Copenhagen stroke study

Objective: To evaluate the outcome of stroke stratified according to both initial stroke severity and initial level of disability. Design: Prospective, consecutive, and community based. Setting: A stroke unit of a hospital in Denmark. This setting receives all acute stroke patients admitted from a well-defined catchment area of 239,886 inhabitants within the City of Copenhagen. Acute treatment as well as all stages of rehabilitation are cared for within the stroke unit regardless of age, stroke severity, and premorbid condition. Patients: 1197 patients with acute stroke. Main Outcome Measures: Primary outcome was measured as death, discharge to nursing home, or to own home. Secondary outcome was measured as neurological deficits and functional disabilities after completed rehabilitation and again 6 months after stroke onset, using the Scandinavian Neurological Stroke Scale and the Barthel Index. Results: Stroke was initially very severe in 223 (19%) of the patients, severe in 171 (14%), moderate in 316 (26%), and mild in 487 (41%) patients. Two hundred and fifty (21%) patients died during hospital stay, 177 (15%) were discharged to nursing home, and 770 (64%) patients were discharged to their own home. After completed rehabilitation, 11% of survivors still had severe or very severe neurological deficits, 11% had moderate deficits, and 78% had no or only mild deficits; 20% were severely or very severely disabled, 8% were moderately disabled, 26% were mildly disabled, and 46% had no disability in activities of daily living. Detailed information on outcome stratified according to initial stroke severity/disability also is presented. Conclusions: This study provides a thorough description of the needs for stroke rehabilitation in the community and the amount of postrehabilitation disability in stroke survivors. For outcome prediction, the results can be used as a reliable tool for prognostication of the chances (or risks) of various outcomes in patients characterized by initial degree of stroke severity and/or functional disability using simple, reliable scores in the acute phase of stroke. However, the results should not be used as a guideline for selecting patients for rehabilitation in the acute phase because even the most severe cases regularly experience meaningful improvement during rehabilitation.

Outcome and time course of recovery in stroke. Part II: Time course of recovery. The copenhagen stroke study

Objective: To determine the time course of both neurological and functional recovery from stroke. Design: Prospective, consecutive, and community based. Setting: The stroke unit of a hospital in Copenhagen, Denmark. This setting receives all acute stroke patients admitted from a well-defined catchment area of 239,886 inhabitants within the city of Copenhagen. Acute treatment as well as all stages of rehabilitation are cared for within the stroke unit regardless of age, stroke severity, and premorbid condition. Patients: 1,197 patients with acute stroke. Main Outcome Measures: Weekly examinations of neurological deficits (using the Scandinavian Neurological Stroke Scale) and functional disabilities (Activity of Daily Living (ADL) measured by the Barthel Index) were performed from the time of acute admission to the end of rehabilitation. These evaluations were repeated 6 months poststroke. Time course of recovery was stratified according to initial stroke severity and disability. Results: Functional recovery was completed within 12.5 weeks (95% confidence interval (CI) 11.6 to 13.4) from stroke onset in 95% of the patients. However, 80% of the patients had reached their best ADL function within 6 weeks (CI 5.3 to 6.7) from onset. The time course of functional recovery was strongly related to initial stroke severity. Best ADL function was reached within 8.5 weeks (CI 8 to 9) in patients with initially mild strokes, within 13 weeks (CI 12 to 14) in patients with moderate strokes, within 17 weeks (CI 15 to 19) in patients with severe strokes, and within 20 weeks (CI 16 to 24) in patients with very severe strokes. After these time-points, no significant changes occurred. However, a valid prognosis of functional outcome can be made much earlier. Best ADL function was reached by 80% of the patients with initially mild strokes within 3 weeks (CI 2.6 to 3.4), within 7 weeks (CI 6 to 8) of the patients with moderate strokes, and within 11.5 weeks (CI 10 to 13) of the patients with severe and very severe strokes. The time course of neurological recovery followed a pattern similar to that of functional recovery, but preceeded functional recovery by 2 weeks on average. Conclusions: A reliable prognosis can in all stroke patients be made within 12 weeks from stroke onset. Even in patients with severe and very severe strokes, neurological and functional recovery should not be expected after the first 5 months.

Recovery of walking function in stroke patients: The copenhagen stroke study

Time course and degree of the recovery of walking function after stroke and the influence of initial lower extremity (LE) paresis were studied prospectively in a community-based population of 804 consecutive acute stroke patients. Walking function and degree of LE paresis were assessed weekly using the Barthel index and the Scandinavian Neurological Stroke scale, respectively. Initially, 51% had no walking function, 12% could walk with assistance, and 37% had independent walking function. At the end of rehabilitation, 21% had died, 18% had no walking function, 11% could walk with assistance, and 50% had independent walking function. Recovery of walking function occurs in 95% of the patients within the first 11 weeks after stroke. The time and the degree of recovery are related to both the degree of initial impairment of walking function and to the severity of LE paresis, p < .0001. A valid prognosis of walking function in patients with initially no/mild/moderate leg paresis can be made in 3 weeks, and further recovery should not be expected after 9 weeks. A valid prognosis of walking function in patients with initially severe leg paresis or paralysis can be made in 6 weeks, and further improvement of walking function should not be expected later than 11 weeks after stroke.

Effect of blood pressure and diabetes on stroke in progression

SummaryProgression of acute stroke after arrival at hospital is frequent and the prognosis severe. However, risk factors and mechanisms behind progression are largely unknown. A prospective, community-based study of 868 patients with acute stroke was undertaken to discover factors of importance in the development of stroke in progression.Diagnosis of progression was based on the Scandinavian Neurological Stroke Scale. Patients were divided according to whether progression occurred early (within 36 hours from stroke onset) or late (within the first week from onset). Results were analysed by comparing patients with and without progression. Marked progression developed in 32%. Risk factors for early progression were identified as systolic blood pressure on admission (decreased the relative risk by 0·66 per 20 mm Hg increase, 95% CI 0·55-0·83) and diabetes (increased the relative risk by 1·9, 95% Cl 1·1-3·3). Stroke severity was the only risk factor found in late progression (OR 1·4 per 20-point increase in stroke severity, 95% Cl 1·1-1·7). These relations were independent of age, sex, blood glucose, heart disease, and other stroke risk factors.Early progression is related to systolic blood pressure and diabetes. Late progression is related to initial stroke severity. Although this study does not prove that a causal relationship exists between systolic blood pressure and the development of early progression, such a relationship would, however, explain our findings.

Reliability of Scandinavian Neurological Stroke Scale

The Scandinavian hemodilution study in acute ischemic stroke used the neurological scale presented here in assessing prognosis and long-term outcome. The purpose of the present study was to test its interobserver reliability. The scale consists of two parts: one for assessing the acute prognosis and one for assessing the neurological deficit acutely and at follow-up. The items rated are: consciousness, gaze palsy, Iimb weakness, dysphasia, orientation, facial palsy and gait. Fifty acute stroke patients were rated by 2 doctors each. The agreement rates were corrected for chance (kappa statistics). Interobserver agreement was good to excellent with weighted kappa values ranging from 0.688 to 0.912. Patients who died within 6 weeks had a lower prognostic score than the survivors. The long-term scores of 2 observers were highly correlated (R = 0.954). The scale provides a reliable instrument for stratification of stroke patients and for evaluation of long-term outcome.