None listed
Conditions
Brief summary
The link between carotid artery disease and stroke is well defined in severe carotid artery stenosis. The link between carotid artery disease, cerebral perfusion, and cognitive function, is less well characterised, particularly in the absence of clinical stroke. Characterising the relationship between carotid stenosis, cerebral perfusion, and cognitive function is relevant to 1). understanding the role of carotid intervention in improving cerebral perfusion and cognitive function and, thereby, dementia prevention; 2). reconsidering the threshold for intervention in those patients who are judged ‘asymptomatic’ by current criteria (whereby indications for intervention are based on stroke risk reduction); and 3). examining whether the two distinct forms of intervention for carotid stenosis (carotid endarterectomy and carotid artery stenting) have different impacts on cognitive function. Alongside our study of the impact of intervention for carotid stenosis and cognition, we will also examine relationships between changes in cognition and quality of life. If improvement in cerebral perfusion and cognitive function in patients treated for asymptomatic carotid artery stenosis can be demonstrated, this would impact significantly on decision making and treatment for these patients with respect to the prevention of cognitive decline. The overarching aim of this research is to determine whether changes in cognitive function occur in older adults following intervention for carotid artery stenosis. The primary objectives are to investigate whether: 1) carotid endarterectomy (CEA) improves cognitive function in patients with symptomatic and asymptomatic carotid artery stenosis, 2) changes in cognitive function following CEA are related to changes in cerebral blood flow and cerebrovascular reserve (CVR) in patients with symptomatic and asymptomatic carotid artery stenosis, 4) changes in cognitive function following CEA are related to findings on MRI, and specifically, on arterial spin-labelled cerebral perfusion imaging, 5) changes in cognitive function following CEA are independent of changes in mood scores, 6) changes in cognitive function following CEA are related to changes in quality of life.
Interventions
Cerebral perfusion (as measured by cerebral blood flow on transcranial doppler, cerebral oximetry on near-infrared spectroscopy, and magnetic resonance imaging with arterial spin labelling protocols and diffusion weighted imaging), and cognitive function (as measured by CogState, DKEFS Verbal Fluency test, and Stroop test) will be measured pre-intervention/1 week post-intervention/4 weeks post-intervention/3 months post-intervention in patients who undergo either carotid endarterectomy for high-
Cerebral perfusion (as measured by cerebral blood flow on transcranial doppler, cerebral oximetry on near-infrared spectroscopy, and magnetic resonance imaging with arterial spin labelling protocols and diffusion weighted imaging), and cognitive function (as measured by CogState, DKEFS Verbal Fluency test, and Stroop test) will be measured pre-intervention/1 week post-intervention/4 weeks post-intervention/3 months post-intervention in patients who undergo either carotid endarterectomy for high-grade carotid artery stenoses for stroke risk reduction (under current algorithms and evidence for carotid intervention). Cerebrovascular reserve as per Ringelstein calculations will also be measured pre-intervention/4 weeks post-intervention/3 months post-intervention using hypocapnic (baseline minus 6mmHg EtCO2), room air, 3% CO2 inhalation, and 6% CO2 inhalation.
Sponsors
Dr Shirley Jansen
Eligibility
Sex/Gender
All
Age
45 Years to 89 Years
Healthy volunteers
Yes
Inclusion criteria
Patients 45-89 years of age planned for carotid endarterectomy or carotid artery stenting of high-grade carotid stenoses for stroke risk reduction. Healthy control group: 45-89 years of age, age and education matched volunteers/spouses.
Exclusion criteria
Non-English speaking Functional impairment impeding physical ability to participate in cognitive testing Diagnosed dementia Haemorrhagic stroke Stroke post-operatively On neuro-modulating drugs
Outcome results
None listed