Risk Factors for Cerebrovascular Disease as Correlates of Cognitive Function in a Stroke-Free Cohort

We investigated the relationship between risk factors for cerebrovascular disease and cognitive function in 249 stroke-free community volunteers (age, 70.8±6.7 years; education, 12.3±4.6 years) who were given tests of memory, language, visuospatial, abstract reasoning, and attentional skills. Using logistic regression analyses, we examined hypertension, diabetes mellitus, myocardial infarction, angina, hypercholesterolemia, and cigarette smoking as potential correlates of performance within these cognitive domains. Controlling for demographic factors within the logistic models, diabetes mellitus was a significant independent correlate of abstract reasoning deficits (odds ratio, 10.9; 95% confidence interval, 2.2 to 54.9) and visuospatial dysfunction (odds ratio, 3.5; confidence interval, 1.2 to 10.7), while hypercholesterolemia was a significant independent correlate of memory dysfunction (odds ratio, 3.0; confidence interval, 1.4 to 6.6). Prolonged exposure to vascular risk factors such as diabetes mellitus and hypercholesterolemia may lead to atherosclerotic disease, possibly resulting in "silent" infarctions or impaired cerebral blood flow and a decline in cognitive functioning

Influence of Education and Occupation on the Incidence of Alzheimer's Disease

Objective. —Several cross-sectional studies have found an association between Alzheimer's disease (AD) and limited educational experience. It has been difficult to establish whether educational experience is a risk factor for AD because educational attainment can influence performance on diagnostic tests. This study was designed to determine whether limited educational level and occupational attainment are risk factors for incident dementia. Design. —Cohort incidence study. Setting. —General community. Participants. —A total of 593 nondemented individuals aged 60 years or older who were listed in a registry of individuals at risk for dementia in North Manhattan, NY, were identified and followed up. Interventions. —We reexamined subjects 1 to 4 years later with the identical standardized neurological and neuropsychological measures. Main Outcome Measure. —Incident dementia. Results. —We used Cox proportional hazards models, adjusting for age and gender, to estimate the relative risk (RR) of incident dementia associated with low educational and occupational attainment. Of the 593 subjects, 106 became demented; all but five of these met research criteria for AD. The risk of dementia was increased in subjects with either low education (RR, 2.02; 95% confidence interval [CI], 1.33 to 3.06) or low lifetime occupational attainment (RR, 2.25; 95% CI, 1.32 to 3.84). Risk was greatest for subjects with both low education and low life-time occupational attainment (RR, 2.87; 95% CI, 1.32 to 3.84). Conclusions. —The data suggest that increased educational and occupational attainment may reduce the risk of incident AD, either by decreasing ease of clinical detection of AD or by imparting a reserve that delays the onset of clinical manifestations

Dementia after Stroke Increases the Risk of Long-Term Stroke Recurrence

Background: Although risk factors for first stroke have been identified, the predictors of long-term stroke recurrence are less well understood. We performed the present study to determine whether dementia diagnosed three months after stroke onset is an independent risk factor for long-term stroke recurrence. Methods: We examined 242 patients (age = 72.0 ± 8.7 years) hospitalized with acute ischemic stroke who had survived the first three months without recurrence and followed them to identify predictors of long-term stroke recurrence. We diagnosed dementia three months after stroke using modified DSM-III-R criteria based on neuropsychological and functional assessments. The effects of conventional stroke risk factors and dementia status on survival free of recurrence were estimated using Kaplan-Meier analyses, and the relative risks (RR) of recurrence were calculated using Cox proportional hazards models. Results: Dementia (RR = 2.71, 95% CI = 1.36 to 5.42); cardiac disease (RR = 2.18, CI = 1.15 to 4.12); and sex, with women at higher risk (RR = 2.03, CI = 1.01 to 4.10), were significant independent predictors of recurrence, while education (RR = 1.90, CI = 0.77 to 4.68), admission systolic blood pressure >160 mm Hg (RR = 1.80, CI = 0.94 to 3.44) and alcohol intake exceeding 160 grams per week (RR = 1.86, CI = 0.79 to 4.38) were weakly related. Conclusions: Our results suggest that dementia significantly increases the risk of long-term stroke recurrence, with additional independent contributions by cardiac disease and sex. Cognitive impairment may be a surrogate marker for multiple vascular risk factors and larger infarct volume that may serve to increase the risk of recurrence. Alternatively, less aggressive medical management of stroke patients with cognitive impairment or noncompliance of such patients with medical therapy may be bases for an increased rate of stroke recurrence

Dementia in Stroke Survivors in the Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, and Computed Tomographic Findings

We Determined the Prevalence of Dementia in 927 Patients with Acute Ischemic Stroke Aged ≥60 Years in the Stroke Data Bank Cohort based on the Examining Neurologist\u27s Best Judgment Diagnostic Agreement among Examiners Was 68% (K=0.34). of 726 Testable Patients, 116 (16%) Were Demented. Prevalence of Dementia Was Related to Age But Not to Sex, Race, Handedness, Educational Level, or Employment Status Before the Stroke. Previous Stroke and Previous Myocardial Infarction Were Related to Prevalence of Dementia Although Hypertension, Diabetes Mellitus, Atrial Fibrillation, and Previous Use of Antithrombotic Drugs Were Not Prevalence of Dementia Was Most Frequent in Patients with Infarcts Due to Large-Artery Atherosclerosis and in Those with Infarcts of Unknown Cause. Computed Tomographic Findings Related to Prevalence of Dementia Included Infarct Number, Infarct Site, and Cortical Atrophy. among 610 Patients Who Were Not Demented at Stroke Onset, We Used Methods of Survival Analysis to Determine the Incidence of Dementia Occurring during the 2-Year Follow-Up. Incidence of Dementia Was Related to Age But Not Sex. based on Logistic Regression Analysis, the Probability of New-Onset Dementia at 1 Year Was 5.4% for a Patient Aged 60 Years and 10.4% for a Patient Aged 90 Years. with a Multivariate Proportional Hazards Model, the Most Important Predictors of Incidence of Dementia Were a Previous Stroke and the Presence of Cortical Atrophy at Stroke Onset. © 1990 American Heart Association, Inc

Thalamic Stroke: Presentation and Prognosis of Infarcts and Hemorrhages

Thalamic Strokes in 62 Patients Selected from the Stroke Data Bank Were Studied to Determine Differences among 18 Infarctions (INF), 23 Localized Hemorrhages (ICH), and 21 Hematomas with Ventricular Extension (IVH). Stupor or Coma at Onset Occurred More Frequently in the IVH (62%) Than in the INF (6%) or ICH (13%) Groups and Was Reflected in Significantly Lower Median Glasgow Coma Scores in the IVH Group (7) Than in the INF (15) and ICH (14) Groups. Although Ocular Movements Were More Frequently Abnormal in the IVH Group Compared with the ICH and INF Groups, No Significant Differences Were Found in the Frequency of Motor or Sensory Deficits. among the 62 Strokes, 32 Had Restricted Lesions of the Posterolateral (N=9), Anterior (N=3), Paramedian (N=7), and Dorsal (N=13) Portions of the Thalamus. Differences in Consciousness and in Motor, Sensory, and Oculomotor Deficits Were Found among the Topographic Subgroups. Stroke-Related Deaths Occurred in 52% of IVH Cases, 13% of ICH Cases, and No Cases of INF. Median Lesion Volume as Detected with Computed Tomography Was Greater in Hemorrhages (INF, 2 Cm3; ICH, 10 Cm3; IVH, 16 Cm3), with Mortality Related to Increasing Hematoma Size. Coma, Glasgow Coma Score Lower Than 9, Weakness Score Greater Than 15 of a Possible 30, Abnormal Ocular Movements, and Fixed Pupils Were Also Associated with Stroke-Related Mortality. We Conclude that the Initial Neurologic Syndrome Does Not Discriminate Infarcts from Intrathalamic Hemorrhages. Ventricular Extension, However, Causes Significantly More Severe Deficits and Higher Mortality. © 1992 Arch Neurol All Rights Reserved

The Determination of Clinically Meaningful Cognitive Decline: Development and Use of an Alternative Method

Statistical methods traditionally used in the analysis of change (e.g., repeated measures ANOVA) may be inadequate for the investigation of cognitive decline if a study's effect size is small, the variance within groups is heterogeneous, or the statistical power is low. To examine an alternative approach to the determination of clinically meaningful cognitive decline and investigate whether such decline occurs during the first year after stroke, we administered a neuropsychological test battery to 172 patients (age = 70.3 +/- 7.6 years; education = 10.3 +/- 4.7 years) 3 and 12 months after stroke and 199 nondemented stroke-free control subjects (age = 71.1 +/- 6.4 years; education = 12.8 +/- 4.2 years) on two occasions 12 months apart. Two neuropsychologists classified each subject's test performance as having declined, improved, or remained stable based solely on clinical judgment. Reliability of the rating of decline versus the pooled rating of improvement/stability was excellent (kappa = 0.79). The two rating groups differed significantly and in the appropriate directions in change on most tests. While a MANOVA comparing the stroke and control groups on change in test scores was not significant, logistic regression analysis determined that a rating of clinically meaningful cognitive decline was associated with stroke status (Odds Ratio = 1.8, 95% Confidence Interval = 1.0 to 3.2), while adjusting for demographic factors. We propose that this alternative approach to the analysis of cognitive change can facilitate the recognition of decline in subgroups of subjects. It would be valuable as an adjunct to studies of the incidence of dementia, for example, in which the recognition of cognitive decline might be difficult in highly educated patients whose baseline level of performance is far above the cutoffs operationalized for the diagnosis of dementia

Higher cortical function deficits among acute stroke patients: The stroke data bank experience

Objectives. Both the number and type of higher cortical function deficits (HCFD) in acute stroke patients are important diagnostically and for gauging the extent of neurological deficits. Methods. The Stroke Data Bank (SDB) provided a large prospective data base for such evaluation. Thirty-one different HCFDs, each defined in the SDB manual, were considered. Results. Of 1,805 patients in the SDB, 641 instances of HCFD in 422 patients were recorded in alert patients at initial examination (within the first 7 to 10 days of ictus). Aphasia (41%) was the most commonly found HCFD, followed by neglect syndrome (27.2%), apraxia (11.7%), and anosognosia (11.1%). Agnosia (3.9%), alexia (3.3%), and aprosodia (1.5%) were less frequently found HCFDs. Cardioembolic infarct was most likely to have associated HCFDs (66%), and lacunar infarction was least likely to be accompanied by HCFDs (6%), with infarction caused by large artery thrombosis (50%) and infarct of undetermined cause (47%) having similar frequencies. The co-occurrence of sensory and motor deficits among the eight major subgroups of HCFD showed that neglect syndrome, apraxia, and anosognosia were most likely to be associated with long tract signs, whereas alexia, aprosodia, and agnosia invariably were not associated with sensorimotor impairment. Approximately half of aphasic patients had associated sensorimotor impairment. Conclusion. Our findings show that higher cortical function deficits are prevalent in the acute phase of stroke, particularly aphasia and neglect syndromes. They are more often associated with nonlacunar stroke and some are less likely to be associated with any sensorimotor deficits

Sex Differences in the Representation of Visuospatial Functions in the Human Brain

Sex differences in the representation of visuospatial functions in the human brain were investigated in 20 subjects with right hemisphere stroke and 40 stroke-free control subjects with the Complex Figure Test, WAIS-R Block Design, and Judgment of Line Orientation. The WAIS-R Similarities subtest was administered as a measure of verbal reasoning. The stroke and contro] groups were composed of equal proportions of males and females, and the male and femalestroke groups were matched for location and volume of infarction. A multivariate analysis of covariance determined that the interaction between stroke status and sex (p<.05), as well as the main effects for stroke status (p<.001) and sex (p<.001), were significantly related to visuospatial performance. None of these variables was significantly related to WAIS-R Similarities performance. The results of this study suggest that females may be disproportionately impaired in visuospatial functioning relative to males following right hemisphere stroke. We propose that visuospatial functions are bilaterally represented in the brains of males, allowing them to rely upon left hemisphere visuospatial systems following right hemisphere stroke, and that these functions are represented in the right hemisphere of females, resulting in their disproportionate impairment despite comparable lesions

Disorientation following stroke: Frequency, course, and clinical correlates

To investigate the frequency, course, and clinical correlates of disorientation following stroke, we administered the Mini-Mental State Examination orientation subtest to 177 alert patients 7–10 days and 3 months after stroke and 240 stroke-free nondemented subjects. Disorientation was defined as a score ≤ 8/10. Seventy-two (40.7%) of the patients were disoriented 7–10 days after stroke and 39 patients (22.0% of the sample) remained disoriented 3 months later. A logistic regression analysis determined that persistent disorientation was significantly related to stroke status [odds ratio (OR)=5.8], after adjusting for memory and attentional deficits and demographic variables. Among stroke patients, disorientation was associated with severe hemispheral stroke syndromes (OR=7.7), but not infarct location or vascular risk factor history, after adjusting for memory and attentional deficits and demographic variables. Sensitivity and specificity analyses determined that disorientation was an inaccurate marker for dementia or deficits in memory or attention, while intact orientation was associated with a low probability of dementia or memory dysfunction in most patients but not preserved attention. We conclude that disorientation is common and persistent following stroke and associated with severe hemispheral stroke syndromes but not infarct location. While disorientation is a poor marker for dementia or deficits in memory or attention, intact orientation should suggest that cognitive functions are likely to be preserved

Influence of Education and Occupation on the Incidence of Alzheimer's Disease

Objective. —Several cross-sectional studies have found an association between Alzheimer's disease (AD) and limited educational experience. It has been difficult to establish whether educational experience is a risk factor for AD because educational attainment can influence performance on diagnostic tests. This study was designed to determine whether limited educational level and occupational attainment are risk factors for incident dementia. Design. —Cohort incidence study. Setting. —General community. Participants. —A total of 593 nondemented individuals aged 60 years or older who were listed in a registry of individuals at risk for dementia in North Manhattan, NY, were identified and followed up. Interventions. —We reexamined subjects 1 to 4 years later with the identical standardized neurological and neuropsychological measures. Main Outcome Measure. —Incident dementia. Results. —We used Cox proportional hazards models, adjusting for age and gender, to estimate the relative risk (RR) of incident dementia associated with low educational and occupational attainment. Of the 593 subjects, 106 became demented; all but five of these met research criteria for AD. The risk of dementia was increased in subjects with either low education (RR, 2.02; 95% confidence interval [CI], 1.33 to 3.06) or low lifetime occupational attainment (RR, 2.25; 95% CI, 1.32 to 3.84). Risk was greatest for subjects with both low education and low life-time occupational attainment (RR, 2.87; 95% CI, 1.32 to 3.84). Conclusions. —The data suggest that increased educational and occupational attainment may reduce the risk of incident AD, either by decreasing ease of clinical detection of AD or by imparting a reserve that delays the onset of clinical manifestations