ACST-1 follow-up study of memory and thinking function
Research type
Research Study
Full title
Does surgery for asymptomatic carotid stenosis reduce the long term risk of dementia, stroke, death and other important health outcomes? Extended UK post-trial follow-up of the Asymptomatic Carotid Surgery Trial (ACST-1). Phase 2
IRAS ID
249685
Contact name
N/A CTRG
Contact email
Sponsor organisation
University of Oxford
ISRCTN Number
ISRCTN26156392
Duration of Study in the UK
1 years, 0 months, 30 days
Research summary
People with narrowing of their carotid artery (an important blood vessel in the neck) are at higher long-term risk of stroke, and there is some suggestion that they are also at higher risk of dementia. We know that an operation to remove tight narrowing in the carotid artery (carotid endarterectomy) reduces the risk of stroke, but we do not know whether it reduces the risk of dementia.
ACST-1 was a large, publicly funded, international trial that randomly allocated participants with tight narrowing of the carotid artery to either immediate carotid surgery (endarterectomy) or to avoid surgery unless they had symptoms. The trial found that endarterectomy reduced the risk of stroke by 5 years and for at least 10 years after the operation.
This follow-up study will help confirm any diagnosis of possible dementia found in the previous electronic data linkage phase of ACST-1 long-term follow-up. The aim of this study is to measure any possible cognitive impairment in UK ACST-1 participants who are still alive, by using a single postal assessment with the validated short form of the 'Informant Questionnaire on Cognitive Decline in the Elderly' (IQCODE).
If we find that endarterectomy for carotid stenosis reduces risk of dementia, this would be important, because treatment of carotid narrowing for this indication is not currently used in the NHS. A reduction in the risk of dementia would alter the risks and benefits of surgery, and provide better information to patients and clinicians.REC name
London - Queen Square Research Ethics Committee
REC reference
18/LO/1866
Date of REC Opinion
3 Dec 2018
REC opinion
Unfavourable Opinion