Carotid Intima-Media Thickness and Midlife Cognitive Function: Impact of Race and Social Disparities in the Bogalusa Heart Study.

BACKGROUND AND OBJECTIVES: Carotid intima-media thickness (c-IMT) is a measurement of atherosclerosis, a progressive disease that develops as early as childhood and has been linked with cognitive impairment and dementia in the elderly. However, the relationship between c-IMT and midlife cognitive function and the race and social disparities in this relationship remain unclear. We examined the association between c-IMT and cognitive function in midlife among Black and White participants from a semirural community-based cohort in Bogalusa, Louisiana. METHODS: In this cross-sectional analysis of participants from the Bogalusa Heart Study, linear regression models were used to determine the association between c-IMT dichotomized above the 50th percentile (>0.87 mm), an a demographically standardized global cognitive score (GCS), and individual cognitive domain-based z scores. Stratified analyses were performed to evaluate the impact of race and the individual's education status. RESULTS: A total of 1,217 participants (age 48 ± 5.28 years) were included; 66% (804) self-identified as White, and 34% (413) self-identified as Black. Of those, 58% (708) were women, and 42% (509) were men. Having a c-IMT ≥50th percentile was inversely associated with GCS (B ± SE -0.39 ± 0.18, p = 0.03), independently of cardiovascular risk factors (CVRFs) and achieved education. The effect remained significant in Black and White participants after adjustment for CVRFs (Black participants: B ± SE -1.25 ± 0.45, p = 0.005; White participants: B ± SE -0.92 ± 0.35, p = 0.008) but not for education. The interaction between c-IMT ≥50th percentile and education was significant (p = 0.03), and stratified analysis showed an association with GCS among those with lower achieved education (B ± SE -0.81 ± 0.33, p = 0.013) independently of major CVRFs. DISCUSSION: Subclinical atherosclerosis, measured as c-IMT, was associated with worse midlife cognitive function, independently of major CVRFs. The association was buffered by education and may be stronger among Black than White participants, likely due to corresponding structural and social determinants. These findings underscore the importance of establishing preventive measures in midlife and suggest subclinical atherosclerosis as a potential target to prevent cognitive decline.

Cardiovascular Health Trajectories From Childhood Through Middle Age and Their Association With Subclinical Atherosclerosis.

Importance: Cross-sectional measures of cardiovascular health (CVH) have been associated with cardiovascular disease in older age, but little is known about longitudinal trajectories in CVH and their association with subclinical atherosclerosis in middle age. Objectives: To model long-term patterns in CVH starting in childhood and to assess their association with subclinical atherosclerosis in middle age. Design, Setting, and Participants: This cohort study used data from 5 prospective cardiovascular cohort studies from the United States and Finland from 1973 to 2015. A total of 9388 participants aged 8 to 55 years had at least 3 examinations and were eligible for this study. Statistical analysis was performed from December 1, 2015, to June 1, 2019. Exposures: Clinical CVH factors (body mass index, total cholesterol level, blood pressure, and glucose level) were classified as ideal, intermediate, or poor, and were summed as a clinical CVH score. Group-based latent class modeling identified trajectories in this score over time. Main Outcomes and Measures: Carotid intima-media thickness (cIMT) was measured for participants in 3 cohorts, and high cIMT was defined as a value at or above the 90th percentile. The association between CVH trajectory and cIMT was modeled using both linear and logistic regression adjusted for demographics, baseline health behaviors, and baseline (or proximal) CVH score. Results: Among 9388 participants (5146 [55%] female; 6228 [66%] white; baseline mean [SD] age, 17.5 [7.5] years), 5 distinct trajectory groups were identified: high-late decline (1518 participants [16%]), high-moderate decline (2403 [26%]), high-early decline (3066 [32%]), intermediate-late decline (1475 [16%]), and intermediate-early decline (926 [10%]). The high-late decline group had significantly lower adjusted cIMT vs other trajectory groups (high-late decline: 0.64 mm [95% CI, 0.63-0.65 mm] vs intermediate-early decline: 0.72 mm [95% CI, 0.69-0.75 mm] when adjusted for demographics and baseline smoking, diet, and physical activity; P < .01). The intermediate-early declining group had higher odds of high cIMT (odds ratio, 2.4; 95% CI, 1.3-4.5) compared with the high-late decline group, even after adjustment for baseline or proximal CVH score. Conclusions and Relevance: In this study, CVH declined from childhood into adulthood. Promoting and preserving ideal CVH from early life onward may be associated with reduced CVD risk later in life.