Cognitive function and carotid stenosis: review of the literature

Abstract

Stroke is a known cause of cognitive impairment but the relationship between asymptomatic carotid artery stenosis and cognitive function is not clear. The main risk factors for vascular disease are also related to carotid stenosis and cognitive impairment. The association of high-grade stenosis of the internal carotid artery with cognitive impairment is related to silent embolization and hypoperfusion, but it may also be present without evidence of infarction on magnetic resonance imaging. Carotid stenosis treatment may lead to a decline in cognitive function due to complications related to the procedures (endarterectomy or stenting). On the other hand, reperfusion may improve cognitive impairment. The best treatment choice is unclear, considering possible deterioration of cognitive function related to carotid artery stenosis. There is insufficient evidence to consider cognitive impairment an important factor in determining the therapy for carotid stenosis.

Carotid Artery Stenting and Its Impact on Cognitive Function: A Prospective Observational Study

“…The risk factors of CS also contribute to vascular dementia. 1,3 Hence, the real contribution of CS in cognitive decline independent of the other risk factors must also be studied. Further large scale studies with standardized cognitive assessment are required for a better understanding of the complex nature of the interaction between carotid atherosclerosis and cognition.…”

“…1 Without substantial success in the treatment of degenerative diseases of cognition, the present strategy concerns the targeted and optimal treatment of modifiable risk factors that lead to vascular cognitive impairment (VCI). 1 Carotid atherosclerosis and ca-rotid artery stenosis (CS) are leading causes of stroke in the elderly and thus may add to the burden of vascular dementia. 2 Even when asymptomatic, it may contribute to cognitive decline, possibly due to silent embolization and chronic hypoperfusion, which may make it an independent risk factor for VCI.…”

“…2 Even when asymptomatic, it may contribute to cognitive decline, possibly due to silent embolization and chronic hypoperfusion, which may make it an independent risk factor for VCI. 1 It follows that revascularization may halt or reverse cognitive dysfunction. However, revascularization procedures have also been implicated in a worsen-ing of cognitive function because of increased microemboli, temporary flow interruption from clamping (carotid endarterectomy) or balloon dilatation (carotid artery stenting [CAS]), or hyper-perfusion (post-procedure) related injury.…”

“…3,4 This interaction between CS, revascularization, and cognitive dysfunction remains poorly understood, with the published data showing mixed results. 1,[3][4][5][6][7][8][9] Hence, we conducted a study primarily to determine the effect of extracranial CAS on cognitive function and secondarily to study the immediate and delayed complications in Indian patients.…”

Extracranial Carotid Artery Stenosis: The Effects on Brain and Cognition with a Focus on Resting‐State Functional Connectivity

“…[6][7][8][9] However, the degree of stenosis still represents the major parameter that is considered when choosing the appropriate treatment for this condition in patients who are either asymptomatic or symptomatic for stroke/transient ischemic attack (TIA); 10,11 the treatment can be medical and/or invasive by carotid endarterectomy (CEA) or carotid artery stenting (CAS). 10,11 Apart from the risk of stroke, it is also known from the literature that cognitive impairment is frequently found in patients with asymptomatic ECAS, [12][13][14][15] and different underlying mechanisms have been suggested, including silent microinfarction. 16,17 Further, the use of imaging tools, such as resting-state functional connectivity (rs-fc) magnetic resonance (MR), has allowed the scientific community to study the effects of ECAS on brain circuits.…”