Carotid stenosis and the cognitive function.
While stroke is a known cause of a cognitive impairment, the relationship between a carotid artery stenosis and the cognitive function in individuals without a history of stroke is less clear. A number of risk factors for vascular disease are related to a cognitive impairment. Hypertension, diabetes mellitus, cigarette smoking, and dyslipidemia are also associated with an increased risk of carotid artery disease. Some studies have suggested that a stenosis of the internal carotid artery may be an independent risk factor for a cognitive impairment. A high-grade stenosis of the internal carotid artery may be associated with a cognitive impairment even without evidence of infarction on magnetic resonance imaging. On the other hand, it is fairly common that patients display a normal cognition despite severe carotid artery disease, highlighting the important role of an efficient collateral blood supply. The possible pathomechanisms of a cognitive impairment include silent embolization and hypoperfusion. Carotid endarterectomy or stenting may lead to a decline in the cognitive function in consequence of microembolic ischemia or intraprocedural hypoperfusion. Conversely, perfusion restoration could improve a cognitive dysfunction that might have occurred from a state of chronic hypoperfusion. It is unclear whether these complex interactions ultimately result in a net improvement or a deterioration of the cognitive function. The evidence available at present does not seem strong enough to include consideration of a loss of cognition as a factor in determining the balance of the risks and benefits of therapy for a carotid stenosis.
Sztriha
Laszlo K
LK
Department of Neurology, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary. sztriha@nepsy.szote.u-szeged.hu
Nemeth
Dezso
D
Sefcsik
Tamas
T
Vecsei
Laszlo
L
D016893:Carotid Stenosis / Q000453:epidemiology* / Q000523:psychology* / Q000628:therapy; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D006801:Humans; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors