Although transient ischemic attacks (TIAs) by definition
do not cause lasting neurological deficits, cognitive impairment
has been suggested in patients with carotid artery disease who
have suffered from a TIA. The purpose of our study was to assess
whether patients with carotid artery disease and TIAs are
cognitively impaired, to describe the frequency, nature and
severity of this impairment, and to search for associated
patient characteristics.
Thirty-nine consecutive patients with carotid occlusion
and ipsilateral cerebral or retinal TIAs, and 46 healthy
controls underwent extensive neuropsychological assessment.
Performances were compared group-wise with analysis of variance.
In addition, the presence of cognitive impairment in the
individual patient was determined. Associations between illness
characteristics and cognitive impairment were explored with
regression analysis.
Fifty-four percent of patients were cognitively impaired.
Cognitive deficits were non-specific in nature and mild in
severity. Impairment occurred also in patients with isolated
retinal symptoms and in those without visible ischemic brain
lesions on MRI. Neither the presence of any vascular risk
factor, the side of the symptomatic carotid occlusion, the uni-
or bilaterality of carotid occlusion, nor the number of cerebral
ischemic lesions were predictors of cognitive impairment.
We conclude that about half of the patients with carotid
artery occlusion and ipsilateral TIAs are cognitively impaired.
The presence of cognitive deficits in patients with isolated
retinal symptoms and in those without cerebral ischemic lesions
on MRI argues against an exclusive role for structural brain
damage in the pathogenesis of these deficits.
Key words
cognition disorders - carotid artery disease - transient ischemic attack