Abstract 3849: Subclinical Atherosclerosis Explains Differences in Cognitive Function
Evidence supporting an association between cardiovascular disease (CVD), its risk factors and cognitive impairment is mounting. Few community-based studies have examined the relationship between subclinical atherosclerosis and cognition, and it is not known whether it is related to cognitive function in persons without CVD. We examined the association between subclinical atherosclerosis and cognitive function in healthy men and women (n = 503) with mean age = 60.8 years enrolled in the B Vitamin Atherosclerosis Intervention Trial (BVAIT). Prior to randomization, participants had measures of carotid artery intima-media thickness (CIMT), coronary and aortic calcium and cognition. Six cognitive domains were created grouping 16 tests (z-transformed scores) into putative domains. Multivariable linear regression methods examined the association between cognitive domains and subclinical atherosclerosis dichotomizing CIMT at the 80th percentile and using a composite variable summarizing the presence of atherosclerosis at multiple vascular sites. Models were adjusted for age, gender, race, education, income and depression. Beta coefficients indicated differences in standard deviation units. Individuals with CIMT ≥ 80th percentile performed significantly worse in the global cognitive domain (β = −0.10, SE = 0.05, p = 0.03), and borderline significantly worse in domains of verbal and non-verbal memory (β = −0.15, SE = 0.08, p = 0.08; β = −0.19. SE = 0.10, p = 0.06, respectively) compared to CIMT ≥ 80th percentile. The presence of aortic or coronary calcium was not associated with cognitive function. Individuals with atherosclerosis present in three vascular sites had significantly lower performance in the global cognitive domain (β = −0.14, SE = 0.06, p = 0.02) and in the visuospatial domain (β = −0.23, SE = 0.11, p = 0.03) compared to atherosclerosis at two or fewer sites. Addition of LDL cholesterol, blood pressure, smoking, and homocysteine to models did not alter associations.
These results suggest:
certain cognitive domains are more affected by subclinical atherosclerosis earlier in the CVD process than others;
subclinical atherosclerosis affects cognition through mechanisms independent of standard cardiovascular risk factors.