Dementia as a Predictor of Adverse Outcomes Following Stroke

Abstract

Background and Purpose-Although it is understood that dementia is a risk factor for adverse outcomes, little is known about the predictive validity of the numerous methods that have been proposed for its diagnosis. Thus, we performed the present study to assess the utility of a variety of diagnostic methods in the prediction of adverse outcomes following stroke. Methods-We administered neuropsychological, neurological, and functional examinations to 244 patients (age, 71.7Ϯ8.5 years) 3 months after ischemic stroke. We diagnosed dementia using each of the following methods: (1) neuropsychological testing, requiring deficits in increasing numbers of cognitive domains, both with and without memory impairment, as well as functional impairment; (2) Mini-Mental State Examination (MMSE) score of Ͻ24; and (3) neurologists' clinical judgment. We then used survival analyses to investigate the ability of diagnoses based on those methods to predict death and recurrent stroke during long-term follow-up. Results-Log-rank tests and Cox proportional hazards analyses, with recurrent stroke entered as a time dependent covariate, determined that all of the paradigms were significant predictors of mortality, but the performance of paradigms based on neuropsychological testing was superior to the use of the MMSE and clinical judgment, particularly when memory impairment was required. Log-rank tests determined that paradigms based on neuropsychological testing were the only significant predictors of recurrent stroke and performed best when memory impairment was required. Conclusions-Our results suggest that dementia diagnosis based on neuropsychological assessment and an operationalized paradigm requiring deficits in memory and other cognitive domains is superior to other conventional methods in its ability to identify patients at elevated risk of adverse outcomes following stroke. (Stroke. 1998;29:69-74.)

Poststroke Dementia

“…The proportion of stroke patients with PSD depends mainly on the age range, length of follow-up, and diagnostic criteria. 9,31,32 Some studies involving PSD have been performed on nonprospective 16,33 or nonconsecutive samples 16,[33][34][35] ; some others have excluded hemorrhagic 6 -8,10,13,16,33,36,37 or recurrent 6,8,16,16 strokes; usually, the cognitive status before the stroke has not been considered. 16,34,38 We recruited a series of consecutive, unselected, incident stroke cases who reported to a general secondary hospital in an urban area without other alternative specialized health care facilities.…”

Risk Factors for Early Recurrence After Ischemic Stroke

“…Our failure to find an association between cognitive impairment and early recurrence may have been due to limited statistical power and/or our reliance on only the MMSE as a measure of cognitive function in the early poststroke period. It is possible that a more rigorous assessment of cognitive function with comprehensive neuropsychological testing 47 might have allowed us to recognize a significant effect. In addition, subanalyses revealed a significant association between the MMSE score and a major hemispheric stroke syndrome, with 5 of 138 patients (3.6%) with a MMSE score of Ն24 having a major syndrome compared with 30 of 141 patients (21.3%) with a MMSE Ͻ24, possibly accounting for the lack of significance of the MMSE in our multivariate analysis.…”

Poststroke Memory Function in Nondemented Patients

“…In one study, 42 a linear relation between the size of the infarction and the degree of PMF was found. More circumstantial evidence for a role of stroke severity with respect to PMF comes from a study 41 that found a larger total volume of infarction among those patients who developed poststroke dementia.…”