Hyperglycemia and cognitive outcome after ischemic stroke.

BACKGROUND: Post-stroke hyperglycemia (HG) is associated with poor physical recovery, in particular in patients with cortical stroke. We tested whether HG is also associated with cognitive impairment after ischemic stroke. METHODS: We recruited patients from a prospective consecutive cohort with a first-ever supratentorial infarct. Neuropsychological examination included abstract reasoning, verbal memory, visual memory, visual perception and construction, language, and executive functioning. We related HG (glucose >7.0 mmol/L) to cognition and functional outcome (modified Barthel Index) at baseline and after 6-10 months, and to neurological deficit (National Institutes of Health Stroke Scale) and infarct size at baseline. In additional analyses cortical and subcortical infarcts were considered separately. RESULTS: Of 113 patients, 43 had HG (38%) and 55 had cortical infarcts (49%). Follow-up was obtained from 76 patients (68%). In the acute phase, in patients with cortical infarcts HG was associated with impaired executive function (B=-0.65; 95% confidence limits (CL): -1.3-0.00; p<0.05), larger lesion size (p<0.01), and more severe neurological deficits (p<0.01). These associations were not observed in patients with subcortical infarcts and the association between HG and cognitive functioning at follow-up was not significant in either group. CONCLUSIONS: In first-ever ischemic stroke, HG was not associated with impaired cognition after 6-10 months. In the acute phase of stroke HG was associated with impaired executive function, but only in patients with cortical infarcts.

Acute neglect rehabilitation using repetitive prism adaptation: a randomized placebo-controlled trial.

PURPOSE: At present, prism adaptation is probably the most promising rehabilitation procedure for hemi-neglect. However, randomised controlled trials are lacking and no data are available on the effectiveness of prism adaptation in the treatment of acute neglect. METHODS: We followed sixteen neglect patients using a randomised controlled design in which six patients received four-day-in-a-row placebo treatment (CG) and ten patients received four-day-in-a row experimental treatment with 10 degrees rightward deviating prisms (EG) during their stay on the stroke unit. We examined whether patients in the EG improved faster than the CG by administering three neglect tasks (Schenkenberg Line Bisection, Letter Cancellation, Gainotti Scene Copying) immediately before and after each treatment. Second, we examined whether patients in the EG demonstrated a better long-term outcome at one month post-treatment (Behavioural Inattention Test). RESULTS: Patients in the EG improved faster on spatial tasks (line bisection, cancellation) than the CG but not on visuo-construction. Patients in the EG showed no differences with the CG in neglect outcome at one month post-treatment. CONCLUSIONS: Four consecutive prism sessions produced beneficial effects in patients with acute neglect. However, prism effects were either short-term, or placebo treatment with repeated pointing and/or repeated neglect testing was more helpful than we anticipated. Our results emphasize the importance of a placebo condition and a follow-up in rehabilitation studies.

Cognitive disorders in acute stroke: prevalence and clinical determinants.

BACKGROUND: Although cognitive impairment early after stroke is a powerful predictor of long-term functional dependence and dementia, little is known about the characteristics and determinants of cognitive dysfunction in acute stroke. METHODS: We administered a neuropsychological examination covering 7 cognitive domains to 190 patients within 3 weeks after a first stroke. We also assembled lesion characteristics, clinical factors at admission, demographic characteristics and vascular risk factors. Multivariate logistic regression adjusted for age, gender and education was performed to examine determinants of acute cognitive impairment. RESULTS: Overall, 74% of patients with a cortical stroke, 46% with a subcortical stroke and 43% with an infratentorial stroke demonstrated acute cognitive impairment. Disorders in executive functioning (39%) and visual perception/construction (38%) were the most common. The prevalence and severity of deficits in executive functioning, language, verbal memory and abstract reasoning was more pronounced following left compared to right cortical stroke (all p < 0.05). Intracerebral haemorrhage (OR = 5.6; 95% CI = 1.2-25.4) and cortical involvement of the stroke (OR = 3.6; 95%, CI = 1.3-9.9) were independent determinants of acute cognitive impairment, whereas premorbid moderate alcohol consumption exerted a protective effect (OR = 0.4; 95% CI = 0.1-1.1). CONCLUSIONS: Cognitive impairment is common in the first weeks after stroke, with executive and perceptual disorders being the most frequent. Intracerebral haemorrhage, cortical involvement of the lesion and premorbid moderate alcohol consumption are independently associated with acute cognitive impairment.

Neuropsychological and neuroanatomical correlates of perseverative responses in subacute stroke.

Patients with left-sided neglect frequently show repetitive behaviour on the ipsilesional side, such as re-markings on cancellation tasks or extensive elaboration on drawings. It is unclear whether these perseverative responses occur as a symptom of hemi-neglect or inattention in general, and/or whether they are related to anatomical brain correlates such as lesion location, lesion side or volume. In a first study, we examined the prevalence and neuropsychological correlates of perseverative responses in 206 subacute stroke patients and 63 healthy controls. Perseverative responses were considered present when there was at least one re-marking on the Star Cancellation, and both the degree and spatial distribution of re-markings were examined. A distinction was made between hemi-neglect and non-lateralized inattention. Spatial and verbal working memory were assessed with the Corsi Block Span and the Digit Span. Verbal and non-verbal executive function was assessed with the Visual Elevator and Letter Fluency. Stroke patients without inattention demonstrated re-markings that were related to executive performance, and the degree of perseveration was equally distributed across the sheet. Hemi-neglect patients but not patients with generalized inattention demonstrated more re-markings than controls, suggesting that a lateralized spatial attention bias triggers the perseverative responses. Patients with left and right hemi-neglect showed the same prevalence of perseveration, but the distribution of re-markings was more lateralized towards the ipsilesional side in patients with right-hemispheric stroke. The degree of perseveration in patients with hemi-neglect was related to the severity of the neglect. The goal of the second study on a subset of patients (n = 127) was to determine the neuroanatomical correlates of perseverative responses in the early phase of stroke. Lesion anatomy was administered by indicating involvement of frontal, parietal, temporal, occipital lobe, caudate nucleus, lenticular nucleus and/or thalamus. Lesion volume was calculated using a manual tracing technique. Lesion analyses indicated that perseverative behaviour is strongly associated with lesions involving the caudate nucleus or the lenticular nucleus, independent of lesion volume. The caudate nucleus was an important correlate of perseveration independent of the presence of hemi-neglect. No association was found between lesion side and perseverative responses, in contrast to previous studies. In conclusion, a stroke involving the basal ganglia and the presence of (left- or right-sided) hemi-neglect are two important associates of perseverative responses in the subacute phase of stroke.

Early cognitive impairment predicts long-term depressive symptoms and quality of life after stroke.

OBJECTIVE: The aim of the present study was to examine the predictive value of cognitive impairment in the acute phase after stroke as a risk factor for long-term (six to ten months after stroke) depressive symptoms (DS) and a reduced quality of life (QOL), independent of demographic and neurological predictors. METHODS: We evaluated 143 patients within the first 3 weeks post-stroke. Predictor variables included domain-specific cognitive function, demographic data, vascular risk factors, lesion characteristics, and clinical factors. Predictor variables associated with long-term DS (Montgomery Asberg Depression Rating Scale >or=7) and QOL (Stroke-Specific Quality of Life Scale) were identified with multiple logistic and linear regression. RESULTS: Long-term DS were independently predicted by cognitive impairment at baseline, DS at baseline, female sex, diabetes mellitus, and previous TIA(s). Cognitive impairment, increasing age, and functional dependence predicted a reduced QOL, whereas hypercholesterolaemia predicted a better QOL. Among all cognitive disorders, unilateral neglect was the greatest risk factor for DS after 6 months, whereas a disorder in visual perception and construction affected QOL the most. CONCLUSIONS: Cognitive impairment and vascular risk factors are important predictors of long-term DS and QOL after stroke. The prognostic value of cognition suggests a reactive component in the development or continuation of long-term DS.

Cognitive and functional outcome after intravenous recombinant tissue plasminogen activator treatment in patients with a first symptomatic brain infarct.

OBJECTIVE: To examine whether intravenous recombinant tissue plasminogen activator (rt-PA) treatment given in the acute phase of ischaemic stroke has a favourable effect on cognitive and functional outcome at six months post-stroke. METHODS: The present study included 92 patients with a first-ever symptomatic infarct, of whom 25 (27%) were subjected to rt-PA treatment in the first three hours post-stroke. Multivariate logistic regression analyses adjusted for stroke severity, education, age, and sex were performed to examine whether rt-PA treatment influenced cognitive outcome (assessed with a neuropsychological examination covering 7 cognitive domains), basic ADL independence (modified Barthel Index > or = 19), and instrumental ADL independence (Frenchay Activities Index > or = 15) after six months. RESULTS: The adjusted odds ratio for intact cognition was 1.0 (95% CI 0.2 to 4.3), that for basic ADL outcome 13.5 (95 % CI 1.4 to 129.4) and for instrumental ADL 7.1 (95 % CI 1.2 to 42.2). CONCLUSION: Our findings suggest that rt-PA treatment is associated with a favourable basic and instrumental ADL outcome, but not with a beneficial cognitive outcome after 6 months.

Early neuropsychological evaluation in patients with ischaemic stroke provides valid information.

OBJECTIVES: This study describes the feasibility and validity of neuropsychological evaluation in the early stage post-stroke. Early information on cognitive functioning in stroke patients could improve discharge decision, programming of rehabilitation strategies, and better prepare proxies for the problems they can be presented with in daily life. In this explorative study, our primary focus was on the feasibility of early neuropsychological evaluation. Furthermore, we looked at the possible prognostic relevance of early examination. PATIENTS AND METHODS: Fifty-seven consecutive patients (age 19-80) were enrolled within 4-20 days after their first ischaemic stroke (Modified-Rankin Scale (M-RS): 2-4). Patients were re-tested after 12-24 months, and functional outcome was assessed. RESULTS: In the early stage 44 (77%), patients could complete 82% of the administered tasks. At second evaluation, test performances improved, but a stable test profile was found with respect to abnormalities on the different tasks (P<0.0001). Moreover, initial sum scores of all composite cognitive domains including intellectual functioning (R2=0.80), language (R2=0.76), memory (R2=0.32), perception and visuospatial construction (R2=0.60), attention and psychomotor-functioning (R2=0.80) had significant predictive validity with respect to functional outcome (P<0.001). CONCLUSION: This study supports the feasibility of early neuropsychological evaluation after ischaemic stroke onset and the prognostic validity for cognitive outcome in the long term.

Restrictions of the Mini-Mental State Examination in acute stroke.

While the Mini-Mental State Examination (MMSE) was originally developed to screen for dementia and delirium, many neurologists use this measure as a screening instrument for 'cognitive impairment' in hospitalized stroke patients. However, the validity of the MMSE as such has never been evaluated in acute stroke. We administered the MMSE in addition to a neuropsychological examination covering six cognitive domains to 34 stroke patients (mean interval between stroke and examination, 6.5+/-2.9 days) and 34 healthy controls. The area under the receiver operating characteristic curve (AUC) was calculated in addition to the sensitivity and specificity for various cut-off points on the MMSE. Seventy percent of the patients were impaired in at least one cognitive domain. The accuracy of the MMSE in detecting cognitive impairment was no better than chance (AUC = 0.67; p = 0.13). No optimum MMSE cut-off value could be identified. The MMSE is particularly insensitive to impairments in abstract reasoning, executive functioning, and visual perception/construction.

The prognostic value of domain-specific cognitive abilities in acute first-ever stroke.

OBJECTIVE: To evaluate the prognostic value of domain-specific cognitive abilities in acute stroke with respect to long-term cognitive and functional outcome in addition to neurologic and demographic predictors. METHODS: The authors evaluated 168 patients within the first 3 weeks after first-ever stroke. The prevalence of neuropsychological impairment was calculated vs 75 matched healthy controls. The authors also recorded demographic data, vascular risk factors, lesion characteristics, and clinical factors at admission. Independent predictor variables associated with long-term cognitive impairment (assessed with a follow-up neuropsychological examination) and functional impairment (assessed with the modified Barthel Index and the Frenchay Activities Index) were identified with stepwise multiple logistic regression. Areas under receiver operator characteristic curves were used to compare the predictive value of three models, i.e., a standard medical model, a purely cognitive model, and a model consisting of both medical and cognitive predictors. RESULTS: Thirty-one percent of patients showed long-term cognitive impairment. Basic and instrumental ADL disturbances remained present in 19% and 24% of patients. Domain-specific cognitive functioning predicted cognitive and functional outcome better than any other variable. Moreover, the prediction of instrumental ADL functioning improved when cognitive predictors were added to the standard medical model (p < 0.05). Impairments in abstract reasoning and executive functioning were independent predictors of long-term cognitive impairment. Inattention and perceptual disorders were more important in predicting long-term functional impairment. CONCLUSION: Domain-specific cognitive abilities in the early phase of stroke are excellent independent predictors of long-term cognitive and functional outcome.

Early depressive symptoms after stroke: neuropsychological correlates and lesion characteristics.

OBJECTIVE: To examine the relation between depressive symptoms and specific cognitive functions in patients with a recent stroke and to examine associations with lesion characteristics. METHODS: We studied 126 of 183 consecutive patients within 3 weeks after a first-ever symptomatic stroke (mean interval, 8.3+/-4.3 days). Presence and severity of depressive symptoms was assessed with the Montgomery Asberg Depression Rating Scale. Neuropsychological functioning was examined by means of a detailed neuropsychological examination covering six cognitive domains. We included a healthy control group (N=75) to obtain normative data for the neuropsychological examination. Functional impairment was measured with the modified Barthel Index and the modified Rankin Scale. Symptomatic and preexistent lesion characteristics were determined on CT or MRI. RESULTS: Of the included patients, 40% demonstrated mild and 12% moderate to severe depressive symptoms. Severity of depressive symptoms was related to lesion volume (p=0.008), functional impairment (all p<0.004), and degree of overall cognitive impairment (p=0.005). After adjustment for lesion size, a specific neuropsychological profile emerged in patients with moderate to severe depressive symptoms, affecting primarily memory, visual perception, and language (all p<0.05). No association was found between severity of depressive symptoms and lesion location, presence of preexistent lesions (white matter lesions and silent infarcts), and demographic factors (age, education, and gender). CONCLUSIONS: Moderate or severe symptoms of depression in the early stage poststroke are associated with a specific pattern of cognitive impairment, lesion size, and functional status. We suggest that depressive symptoms early after stroke are, at least in part, a reactive phenomenon secondary to severe cognitive and functional deficits.

Domain-specific cognitive recovery after first-ever stroke: a follow-up study of 111 cases.

The objective of this study is to examine the prognosis of acute cognitive disorders post-stroke, and to evaluate which clinical factors predict domain-specific cognitive recovery. We followed the course of cognitive functioning in 111 stroke patients and 77 healthy controls by administering two neuropsychological examinations with a 6 to 10 month interval (mean interval, 7.5 +/- 1.3 months). The baseline examination was administered within three weeks post-stroke (mean interval, 7.9 +/- 4.2 days). To examine determinants of domain-specific cognitive recovery, we recorded vascular risk factors, clinical variables, and lesion characteristics. Recovery in visual perception/construction (83%) and visual memory (78%) was the most common. An acute cognitive disorder predicted a long-term disorder in the same domain (all p < .05), except for visual perception/construction. Factors associated with poor cognitive recovery were age (all p < .01), preexistent verbal ability (all p < .005), lesion locations involving the temporal (all p < .05), frontal (p < .05) and occipital lobe (allp < .05), lesion volume (p < or = .001), and diabetes mellitus (p < .01). An early neuropsychological examination provides valuable information on long-term cognitive performance. The prognosis of higher-level visual disorders is the most favorable. Cognitive recovery is associated with age, preexistent ability, lesion volume, lesion location, and diabetes mellitus.

[The Location Learning Test as a measure of spatial memory: applicability of a modified administration procedure and normative data]. / De Location Learning Test als maat voor het ruimtelijk geheugen: bruikbaarheid van een nieuwe afnameprocedure en normgegevens.

The Location Learning Test is a neuropsychological test that can be used to assess memory for object locations. The test has originally been developed for the assessment of visuo-spatial memory impairment in patients with dementia. However, ceiling effects may be present in other patient groups. This study has examined the applicability of a modified administration procedure with a shorter presentation duration and longer delay. The test was administered in a group of stroke patients (n = 105), a group of patients with diabetes (n = 93), as well as a group of healthy volunteers (n = 97). The results indicate that the Location Learning Test can be used to discriminate the diabetes and stroke patients from the control group. Furthermore, differences between patients with a left and a right-hemisphere stroke were found. The test has a high correlation with another memory test. The performance of the group healthy volunteers was used to calculate normative data for use in clinical practice.