Early post-stroke cognition in stroke rehabilitation patients predicts functional outcome at 13 months.

OBJECTIVE: To identify prognostic factors associated with functional outcome at 13 months in a sample of stroke rehabilitation patients. Specifically, we hypothesized that cognitive functioning early after stroke would predict long-term functional outcome independently of other factors. METHODS: 163 stroke rehabilitation patients underwent a structured neuropsychological examination 2-3 weeks after hospital admittance, and their functional status was subsequently evaluated 13 months later with the modified Rankin Scale (mRS) as outcome measure. Three predictive models were built using linear regression analyses: a biological model (sociodemographics, apolipoprotein E genotype, prestroke vascular factors, lesion characteristics and neurological stroke-related impairment); a functional model (pre- and early post-stroke cognitive functioning, personal and instrumental activities of daily living, ADL, and depressive symptoms), and a combined model (including significant variables, with p value <0.05, from the biological and functional models). RESULTS: A combined model of 4 variables best predicted long-term functional outcome with explained variance of 49%: neurological impairment (National Institute of Health Stroke Scale; ß = 0.402, p < 0.001), age (ß = 0.233, p = 0.001), post-stroke cognitive functioning (Repeatable Battery of Neuropsychological Status, RBANS; ß = -0.248, p = 0.001) and prestroke personal ADL (Barthel Index; ß = -0.217, p = 0.002). Further linear regression analyses of which RBANS indexes and subtests best predicted long-term functional outcome showed that Coding (ß = -0.484, p < 0.001) and Figure Copy (ß = -0.233, p = 0.002) raw scores at baseline explained 42% of the variance in mRS scores at follow-up. CONCLUSIONS: Early post-stroke cognitive functioning as measured by the RBANS is a significant and independent predictor of long-term functional post-stroke outcome.

Cognitive impairment and the role of the ApoE epsilon4-allele after stroke--a 13 months follow-up study.

OBJECTIVE: To examine the relationship between the ApoE epsilon4 allele and cognitive impairment 13 months after stroke. METHODS: One hundred four stroke rehabilitation patients were cognitively tested on average 18 days after hospital admission and again 13 months later with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The following potential risk factors for post-stroke cognitive impairment (defined by a RBANS total index score below 77.5 points) at 13 months follow-up were analyzed in bivariate and logistic regression analyses: ApoE-genotype, socio-demographic variables, pre-stroke cognitive reduction (The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)), vascular factors, lesion characteristics, and neurological impairment (The National Institute of Health Stroke Scale (NIHSS)). Differences in general cognitive performance (pre-stroke, baseline, and follow-up) across patients with different ApoE-genotypes were analyzed, and lastly differences between epsilon4-carriers and non-carriers for changes in performance in various cognitive domains over the 13 months period were examined. RESULTS: Significant risk factors for cognitive impairment at 13 months were ApoE epsilon4, pre-stroke cognitive reduction (IQCODE 3.44+), previous stroke, and neurological impairment (NIHSS Total Score >5). A significant dose-dependent effect of the ApoE-genotype in relation to overall post-stroke cognitive functioning was found at baseline and follow-up, but not pre-stroke. The epsilon4 carriers showed a significant decline in tests related to verbal learning and memory compared to the non-carriers. CONCLUSIONS: The ApoE epsilon4-allele constitutes an independent risk factor for cognitive impairment at 13 months post-stroke, and is associated with progression of cognitive decline in tasks related to verbal learning and memory.

Association between ApoE epsilon4 and cognitive impairment after stroke.

BACKGROUND AND PURPOSE: The understanding of the contribution of genetic factors to cognitive impairment after stroke is incomplete. The aim of the study was to examine whether the apolipoprotein E epsilon4 allele (ApoE epsilon4) is a risk factor for cognitive impairment in the early phase after stroke. METHODS: The sample comprised 152 Norwegian stroke rehabilitation inpatients (mean age 76.8 years, SD 10.5) examined at a mean of 18.3 days (SD 13.4) after hospital admission. Post-stroke cognitive impairment was assessed with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The following proposed risk factors were analysed: ApoE genotype, demographics (age, sex, education), pre-stroke cognitive reduction [Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)], pre-stroke vascular factors (including previous stroke), stroke characteristics (type, location), and neurological stroke-related impairment [National Institutes of Health Stroke Scale (NIHSS)]. Cognitive impairment was defined as an RBANS total index score < or =1.5 SD below the mean. Multiple logistic regression analyses were performed to find risk factors for post-stroke cognitive impairment. RESULTS: Four variables were found to be independent risk factors for cognitive impairment after stroke: ApoE epsilon4 (OR = 3.7; 95% CI = 1.2-11.6), IQCODE score > or =3.44 (OR = 9.2; 95% = CI 2.3-37.2), total or partial anterior stroke syndromes (OR = 3.2; 95% CI = 1.3-8.0), and NIHSS total score >5 (OR = 7.3; 95% CI = 2.7-19.7). No association between ApoE epsilon4 and pre-stroke cognitive reduction (IQCODE) was found. CONCLUSIONS: The presence of one or two ApoE epsilon4 alleles may be a significant independent risk factor for cognitive impairment in the early phase after stroke.

Factor analysis of the Montgomery Aasberg Depression Rating Scale in an elderly stroke population.

BACKGROUND: Depression is frequent in elderly stroke patients, and the pathophysiology may involve psychological as well as organic mechanisms. AIM: To explore construct validity of the Montgomery Aasberg Depression Rating Scale using factor analysis and investigate whether symptom clusters of depression after stroke are associated with patient characteristics. METHODS: A sample of 163 stroke patients was assessed by the Montgomery Aasberg Depression Rating Scale. Pre-stroke assessment was accomplished by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), the Barthel ADL Index and patient's medical history. Post-stroke assessment was performed with the Mini Mental State Examination (MMSE), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Star Cancellation Test, the Barthel ADL Index, the modified Rankin Scale (mRS) and the National Institute of Health Stroke Scale (NIHSS). Information was collected from the patients' records. A principal components factor analysis followed by oblique rotation was performed. RESULTS: Among the patients, 56.4% scored between 7 and 19 on the Montgomery Aasberg Depression Rating Scale, and 13% had a score above 19. The factor analysis resulted in three factors, called anhedonia (lassitude, inability to feel, suicidal thoughts, loss of appetite), sadness (observed sadness, reported sadness, pessimism) and agitation (inner tension, lack of concentration, disturbed sleep). Anhedonia correlated with cognitive impairment, whereas sadness correlated with sensorimotor and cranial nerve deficits. Agitation had low internal reliability and did not correlate with any systematic patients characteristics. CONCLUSION: We found three distinct factors. The factor anhedonia is related to cognitive impairment, sadness to neurological impairment due to the stroke and agitation to somatic factors not directly related to the stroke.

Depressive symptoms in stroke patients: a 13 month follow-up study of patients referred to a rehabilitation unit.

BACKGROUND: Although depression is known to be frequently associated with stroke, it is nonetheless underdiagnosed and under-treated in this patient population. Its effect on outcome for stroke patients is thought to be substantial, but prediction is complicated by other pre- and post stroke factors. The aims of this study was to describe changes in depressive symptoms in elderly stroke patients across a timespan of one year, to examine risk factor for such changes and to explore whether depressive symptoms have any independent impact upon one year mortality and nursing home placement. METHODS: 194 patients diagnosed with an ischaemic or hemorrhagic stroke was recruited from the Stroke Rehabilitation Unit, Ullevaal University Hospital, Oslo, Norway during the period between March 2005 and August 2006 and followed up for a period of 13 months. Pre-stroke assessment was accomplished by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), the Frenchay Activities Index (FAI), the Barthel ADL Index and patient's medical history. Post-stroke assessment at inclusion and follow-up examination was performed with the Mini Mental State Examination (MMSE), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Star Cancellation Test, the Barthel ADL Index, the modified Rankin Scale (mRS) and the National Institute of Health Stroke Scale (NIHSS). Information was collected from the patients' records. RESULTS: Institutionalization at 13 months was predicted by more depression (MADRS) and cognitive impairment (RBANS) at baseline, together with lower pre-stroke social activity levels (FAI). Two factors predicted death at 13 months: Cognitive impairment (MMSE) and greater age. The prevalence of depression was relatively unchanged from baseline (56%) to 13 month follow-up (48%). Among the patients who were depressed at baseline 55% still had MADRS score above six (persistent depression) at 13 months, while 35% in the non-depressed group at baseline had developed depression (incident depression). Persistent depression was significantly predicted by lower pre-stroke social activity levels (FAI) together with a more severe stroke (NIHSS) and worse overall function (mRS) at baseline. Incident depression was predicted by receipt of municipal home help before the stroke and a lower score on the delayed memory tasks on RBANS at baseline.

Screening for cognitive deficits after stroke: a comparison of three screening tools.

OBJECTIVE: To assess the concurrent validity of three screening tests for focal cognitive impairments after stroke. DESIGN: Comparison of results from the screening tests with those from a more comprehensive neuropsychological battery. SETTING: Stroke rehabilitation wards of a general hospital and a rehabilitation hospital. SUBJECTS: Forty-nine stroke patients (25-91 years, 35% women). MEASURES: Screening tests were the Cognistat, the Screening Instrument for Neuropsychological Impairments in Stroke (SINS) and the Clock Drawing Test. Health professionals, blind to the results of the reference method, did the screening. Reference method was a neuropsychological assessment based on the Norwegian Basic Neuropsychological Assessment, classifying the patients as ;impaired' or ;not impaired' within the following cognitive domains: language, visuospatial function, attention and neglect, apraxia, speed in unaffected arm, and memory. RESULTS: The best sensitivity (95% confidence interval) was achieved for language problems by Cognistat, naming (80%, 44-98); for visuospatial dysfunction, attention deficits and reduced speed, all by SINS visuocognitive (82%, 60-95, 72%, 39-94, and 78%, 56-93, respectively); and for memory problems by Cognistat memory (69%, 52-87). The data were insufficient to assess any subtest for apraxia. Sensitivity in detecting deficits in any domain was 82% (71-94) for the Cognistat composite score, 71% (57-85) for the SINS composite score, and 63% (49-78) for the most sensitive score of the Clock Drawing Test. CONCLUSION: The Cognistat and the SINS may be used as screening instruments for cognitive deficits after stroke, but cannot replace a neuropsychological assessment. The Clock Drawing Test added little to the detection of cognitive deficits.