Cerebrovascular Damage Mediates Relations Between Aortic Stiffness and Memory

Abstract

Aortic stiffness is associated with cognitive decline. Here, we examined the association between carotid-femoral pulse wave velocity and cognitive function and investigated whether cerebrovascular remodeling and parenchymal small vessel disease damage mediate the relation. Analyses were based on 1820 (60% women) participants in the Age, Gene/Environment Susceptibility—Reykjavik Study. Multivariable linear regression models adjusted for vascular and demographic confounders showed that higher carotid-femoral pulse wave velocity was related to lower memory score (standardized β : −0.071±0.023; P =0.002). Cerebrovascular resistance and white matter hyperintensities were each associated with carotid-femoral pulse wave velocity and memory ( P <0.05). Together, cerebrovascular resistance and white matter hyperintensities (total indirect effect: −0.029; 95% CI, −0.043 to −0.017) attenuated the direct relation between carotid-femoral pulse wave velocity and memory (direct effect: −0.042; 95% CI, −0.087 to 0.003; P =0.07) and explained ≈41% of the observed effect. Our results suggest that in older adults, associations between aortic stiffness and memory are mediated by pathways that include cerebral microvascular remodeling and microvascular parenchymal damage.