Ethnic differences in carotid artery diameter and stiffness: the Northern Manhattan Study.

OBJECTIVE: Race/ethnic differences in carotid arterial function and structure exist among those with cerebrovascular disease, but whether differences persist among healthy populations is unknown. Our objective was to investigate differences in carotid artery diameter and stiffness between race/ethnic groups, and examine whether these race/ethnic differences were age-dependent. METHODS: Carotid diameters were assessed by B-mode ultrasound among 1536 participants from the Northern Manhattan Study (NOMAS), and carotid stiffness metrics were calculated. We used multivariable linear regression models to determine the relationship between race/ethnicity and both carotid arterial stiffness and carotid diastolic diameter. RESULTS: Mean participant age was 70 ± 9 years (Hispanics = 68 ± 8, blacks = 72 ± 9, and whites = 74 ± 9, p < 0.0001). Mean DDIAM was 6.2 ± 1.0mm (Hispanics = 6.2 ± 0.9 mm, blacks = 6.3 ± 1.0 mm, and whites = 6.3 ± 1.0 mm, p < 0.005) and mean STIFF was 8.7 ± 6.3 (Hispanics = 8.5 ± 5.7, blacks = 9.2 ± 6.2 and whites = 8.9 ± 6.9, p < 0.02). In a model that adjusted for sociodemographics and vascular risk factors including hypertension, diabetes, dislipidemia, renal function, physical acticity and a history of known coronary artery diseases; age was positively associated with greater DDIAM in Hispanics (p < 0.0001) but not among blacks or whites. Older age was associated with greater stiffness among Hispanics (p < 0.0001) and blacks (p < 0.003), but not among whites. CONCLUSIONS: We found race/ethnic differences in the association between age and arterial stiffness and diameter, including age-dependent arterial dilation observed in Hispanics that was not observed among blacks or whites.