Ultrasound Markers of Carotid Atherosclerosis and Cognition: The Northern Manhattan Study
AbstractBackground and Purpose—
Ultrasound markers of carotid atherosclerosis may be related to cognitive status. We hypothesized that individuals with greater carotid intima–media thickness (cIMT) and carotid plaque burden would exhibit worse cognition.Methods—
One thousand one hundred sixty-six stroke-free participants from the NOMAS (Northern Manhattan Study) underwent carotid ultrasound and neuropsychological examination. Among them, 826 underwent a second neuropsychological examination an average of 5 years later. cIMT and plaque were assessed by a standardized B-mode ultrasound imaging and reading protocol. We used multivariable linear regression to examine cIMT, carotid plaque presence, and carotid plaque area as correlates of domain-specific neuropsychological Z scores cross-sectionally and over time. We also investigated possible effect modification by APOE ε4 allele, age, and race/ethnicity.Results—
Participants had a mean (SD) age of 70 (9) years and were 60% women, 66% Hispanic, 15% white, and 18% black. Those with greater cIMT exhibited worse episodic memory after adjustment for demographics and vascular risk factors (β=−0.60; P=0.04). APOE ε4 carriers with greater cIMT exhibited worse episodic memory (β=−1.31; P=0.04), semantic memory (β=−1.45; P=0.01), and processing speed (β=−1.21; P=0.03). Participants with greater cIMT at baseline did not exhibit significantly greater cognitive decline after adjustment. APOE ε4noncarriers with greater cIMT exhibited greater declines in executive function (β=−0.98; P=0.06). Carotid plaque burden was not significantly associated with cognition at baseline or over time.Conclusions—
Subclinical carotid atherosclerosis was associated with worse cognition among those at higher risk for Alzheimer disease. Interventions targeting early stages of atherosclerosis may modify cognitive aging.