Cognitive impairment and risk of stroke in the older population

Prediction of functional rehabilitation outcomes in clients with stroke

OBJECTIVES

To evaluate the validity of the Neurobehavioral Cognitive Status Examination (NCSE or Cognistat) and to determine its effects in order to estimate the functional outcomes of survivors with stroke.

METHODS

The present study first studied the factor structure NCSE in 148 Chinese survivors with stroke (aged 45-91 years). They were admitted to hospital consecutively and recruited prospectively. The relationship of NCSE with Functional Independence Measures (FIM), a set of measures commonly adopted as an indicator of the outcome of rehabilitation, was studied.

RESULTS

One hundred and forty-eight patients with stroke (49.3% male, 50.7% female), with a mean age of 70.38 and an average number of years of education of 3.50 years joined the study. A two-factor NCSE structure was obtained, namely verbal-spatial and integrated cognition, accounting for 62.77% of the variance. A significant relationship between NCSE factors and the functional status of clients with stroke on admission and upon discharge, as well as age, years of education and length of hospital stay were indicated.

CONCLUSIONS

This study supports a systematic relationship between cognitive factors and functional outcome in Chinese patients with stroke. Similarities and differences in the NCSE factor structure between the population with stroke and general neurological populations were discussed and the utility of NCSE in stroke rehabilitation, such as its predictive validity in functional independence is suggested.

Cognitive Functioning as a Predictor of Ischemic Stroke Incidence

BACKGROUND

Some studies have suggested that cognitive impairment is related to subsequent stroke incidence. The present study investigated the role of cognitive impairment as a predictor of ischemic stroke incidence in the Atherosclerosis Risk in Communities (ARIC) cohort.

METHODS

The study population consisted of 11,958 men and women 48-67 years of age in 4 U.S. communities, followed from January 1, 1990 through December 31, 1997. Cognitive performance was evaluated at the second (1990-1992) visit of the ARIC Study using 3 instruments. We identified incident strokes by means of hospital record and death certificate reviews, as well as annual telephone follow up.

RESULTS

We found no consistent associations or trends between any of the cognitive test results and ischemic stroke incidence after multiple adjustment for confounding variables. Hazard ratios for the lowest compared with the highest quartiles were 1.5 (95% confidence interval [CI] = 0.9-2.6), 1.1 (95% CI = 0.6-2.1), and 1.0 (95% CI = 0.6-1.8) for the Delayed Word Recall Test, Digit Symbol Subtest of the Wechsler Adult Intelligence Scale-Revised, and Word Fluency Test, respectively.

CONCLUSIONS

The findings of the present study of relatively young subjects did not replicate the association between cognitive impairment and stroke incidence found in studies in older populations. This could be the result of the younger ages of our cohort members or the differences in cognitive tests.

Are vascular factors involved in Alzheimer's disease? Facts and theories

The hypothesis that vascular factors may contribute to the development of Alzheimer's disease (AD) is supported by epidemiologic and pathologic observations. Arterial hypertension and diabetes have been found to be associated not only with vascular dementia, but also with AD; in addition, the treatment of hypertension with calcium antagonists seems to prevent degenerative dementias. Hypertension and hyperinsulinemia favor the deposition of amyloid substance in the brain. The histopathology of AD is marked not only by neurofibrillary tangles and senile plaques, but also by macro and micro congophilic angiopathy and ischemic white matter rarefaction. The specific AD pathological lesions, if isolated, are not able to lead to an evident clinical picture of dementia, which, on the contrary, becomes evident when vascular, mainly subcortical, lesions are associated. These and other observations suggest that vascular factors may have a role in the development of AD. An aggressive approach to these factors could be of value in the prevention of AD.