ABSTRACT NUMBER: ESOC2026A183 ASYMPTOMATIC CAROTID ARTERY STENOSIS, COGNITIVE DECLINE AND DEMENTIA: A PROSPECTIVE POPULATION-BASED COHORT STUDY

Abstract Background and aims Asymptomatic carotid artery stenosis (ACAS) increases the risk of stroke, but it is uncertain whether individuals with >50% stenosis benefit from endovascular or surgical intervention. Additional benefit of carotid revascularisation on cognition may tilt the balance in favour of intervention, but few longitudinal studies have assessed the effect of ACAS on dementia and cognitive decline. Methods Between 2007-2014, dementia-free participants of the population-based Rotterdam Study underwent carotid ultrasound, followed by carotid MRI if intimal media thickness was >2.5mm. All participants underwent repeated cognitive assessments and were followed for dementia. We determined the effect of ACAS on dementia using multivariable Cox models, and on cognitive trajectories (g-factor) using multivariable linear mixed-effects models. Results Of 4266 participants (mean age: 67.5y, 55.6% women), 481 (11%) had plaque without stenosis, 987 (23%) had 1-49% stenosis, 107 (2.5%) had 50-99% stenosis, 15 (0.4%) had occlusion, and 276 developed dementia (mean follow-up: 7.5y). Compared to individuals without carotid atherosclerosis, risk of dementia was increased in the presence of plaque without stenosis (HR: 1.42 [95%CI: 1.02−1.96]) and occlusion (3.86 [1.34−11.07]), but not with 1-49% (1.01 [0.75−1.37]), 50-99% (0.96 [0.50−1.86]), or 70-99% stenosis (0.75 [0.18−3.12]). Asymptomatic carotid plaque, stenosis, or occlusion did not increase rates of cognitive decline. Conclusions Asymptomatic carotid artery plaque and occlusion increase the risk of dementia, but we found no effect of >50% stenosis on cognitive decline or dementia. These results underscore the role of atherosclerosis in the aetiology of dementia, but do not support consideration of cognitive decline in clinical decision-making on treatment of ACAS. Conflict of interest CVJ. Box: nothing to disclose. AC. Pomp: nothing to disclose. M. Kavousi: nothing to disclose. M.K. Ikram: nothing to disclose. D. Bos: nothing to disclose. FJ Wolters: nothing to disclose Figure 1 - belongs to Conclusions