The effects of carotid artery stiffness on cerebral small vessel disease and cognition

Abstract

AbstractBackgroundCarotid artery stiffness is associated with cognitive impairment and dementia, however, the underlying mechanism remains unknown. We examined the association of carotid artery stiffness with cerebral small vessel disease (CSVD) markers, cognitive impairment, dementia with its subtypes, as well as cognitive performance.MethodIn this case‐control study, 272 subjects from a memory clinic underwent physical and medical evaluation along with carotid ultrasonography, 3T brain magnetic resonance imaging and detailed neuropsychological assessment. Carotid ultrasonography was conducted to assess arterial compliance (AC), pressure‐strain elastic modulus (Ep), β‐index, augmentation index (AI), and pulse wave velocity‐β (PWV‐β). Brain MRIs were graded for white matter hyperintensities (WMH), lacunes, and cerebral microbleeds (CMBs). Participants were classified as no cognitive impairment, cognitive impairment no dementia, as well as dementia and its subtypes; Alzheimer’s disease (AD) and vascular dementia (VaD). Cognition was assessed using NINDS–Canadian Stroke Network harmonization neuropsychological battery.ResultIncreased carotid β‐index (β = 0.73, P<0.001), Ep (β = 0.86, P<0.001), and PWV‐β (β = 0.83, P<0.001) were independently associated with WMH. Ep (OR = 1.42, 95%CI = 1.05–1.93), and PWV‐β (OR = 1.43, 95%CI = 1.05–1.94) were associated with presence of lacunes. Ep was associated with AD (OR = 1.59, 95%CI = 1.01‐2.73) and VaD (OR = 2.23, 95%CI = 1.04‐5.94). Additionally, PWV‐β was associated with VaD (OR = 2.24, 95%CI = 1.07–5.62). All carotid artery stiffness measurements, except AI, were associated with worse performance in global cognition, visuomotor speed and memory after adjusting for age, sex, education, hypertension, diabetes, hyperlipidaemia, cardiovascular disease, and smoking. These associations became attenuated but remained significant with global cognition after adjusting for CSVD markers (β‐index; β = ‐0.27, P = 0.04), Ep; β = ‐0.30, P = 0.03), and PWV‐β; β = ‐0.32, P = 0.02).ConclusionCarotid artery stiffening is associated with WMH, lacunes, and etiologic subtypes of dementia. Carotid artery stiffening is also associated with global cognition independent of CSVD. Elevated carotid artery stiffness may help identify patients at risk for developing CSVD and dementia.