Neuropsychological characteristics of mild vascular cognitive impairment and dementia after stroke

Abstract

Background: Post-stroke cognitive impairment is frequent, with characteristic impairments of attentional and executive performance.

Objective: The study aims to determine whether the profile and severity of impairment in vascular Cognitive Impairment No Dementia (vascular CIND) is intermediate between that seen in stroke patients without significant cognitive impairment and patients with post-stroke dementia and thus to establish if the potential value of vascular CIND is a useful concept for predicting further cognitive decline and dementia in stroke patients.

Methods: Stroke patients (n=381) > 75 were recruited from representative hospital-based stroke registers in Tyneside and Wearside, UK. Sixty six age matched controls were also recruited. A detailed battery of neuropsychological assessments was completed 3 months post stroke.

Results: Deficits of attention (z=5.7; p <0.0001) and executive function (z=5.9; p <0.0001) were seen even in stroke patients without vascular CIND, compared to controls. However, stroke patients with CIND were significantly more impaired again on tests of executive function (z=10.3; p <0.0001) compared to those not meeting CIND criteria; and also had greater impairments of memory (z=10.4; p <0.0001) and language expression (z=10.1; p <0.0001). A similar overall profile of deficits was evident in the CIND and the dementia group, but specific deficits were significantly more pronounced in those with dementia, particularly in orientation (z=7.2; p <0.0001) and memory (z=5.8; p <0.0001).

Conclusions: The current study indicates that attentional and executive impairments are frequent in stroke patients, but deficits of memory, orientation and language are more indicative of CIND and dementia. Further longitudinal studies are required to clarify the relationship between specific lesions and the progression of specific cognitive deficits in post-stroke patients.