The relative contributions of aortic and carotid artery stiffness to CeVD and cognition

Introduction

The relative contributions of aortic and carotid artery stiffness on cognitive impairment and dementia remain unknown. We examined the associations of aortic and carotid artery stiffness with cerebrovascular disease markers, cognition, and dementia subtypes in a memory clinic cohort.

Methods

272 participants underwent applanation tonometry, carotid ultrasonography, 3T brain MRI, and neuropsychological assessment. Aortic stiffness parameters (carotid-femoral pulse wave velocity, aortic augmentation index, and aortic pulse pressure) were obtained with applanation tonometry whilst carotid artery stiffness parameters (β-index, pressure-strain elastic modulus, and pulse- wave velocity-β) were assessed by carotid ultrasonography, from which composite scores for aortic and carotid artery stiffness were calculated. Brain magnetic resonance images were graded for cerebrovascular disease markers, including white matter hyperintensities (WMH), lacunes, cerebral microbleeds, cortical infarcts, and stenosis. Cognition was assessed by the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and the National Institute of Neurological Disorders and Stroke–Canadian Stroke Network harmonization battery in order to classify participants as having no cognitive impairment, cognitive impairment no dementia, or dementia subtyped as Alzheimer disease and vascular dementia.

Results

After considering both aortic and carotid artery stiffness in the same regression models, carotid artery stiffness remained independently and significantly associated with WMH (β=0.78, p<0.001), cortical infarcts (odds ratio [OR], 1.05, p=0.003), vascular dementia (OR, 1.10, p=0.017), MMSE (β=-0.89, p=0.013), global cognition (β=-0.33, p=0.017), and visuomotor speed (β=-0.19, p=0.004). Although aortic stiffness was associated with lacunes (OR, 1.09, p=0.035), and cortical infarcts (OR, 1.063, p=0.016), these associations became non-significant after adjusting for carotid artery stiffness.

Discussion

We found that compared with aortic stiffness, carotid artery stiffness had more robust associations with markers of cerebrovascular disease, vascular dementia, and cognitive function in memory clinic patients. Our study suggests that carotid artery stiffness may have a more salient effect on the brain.