RACE-ETHNICITY AND DETERMINANTS OF CAROTID ATHEROSCLEROSIS IN A MULTIETHNIC POPULATION - THE NORTHERN MANHATTAN STROKE STUDY

Background and Purpose Risk factors for carotid atherosclerosis have b een studied in white populations but infrequently in multiethnic cohor ts. The aim of this study was to determine the importance of race-ethn icity and other factors associated with carotid atherosclerosis in a m ixed population of Hispanics, blacks, and whites. Methods As part of t he Northern Manhattan Stroke Study, 526 stroke-free community resident s (aged greater than or equal to 40 years; 41% men, 59% women; 46% His panic, 31% black, 23% white) were recruited through random-digit diali ng and had vascular risk factor evaluations. Maximum internal carotid artery plaque thickness (MICPT) was measured with B-mode ultrasound. T he frequency distribution of MICPT was examined in the three race-ethn ic groups, and multivariate regression was performed to identify facto rs that were independently associated with MICPT. Results Mean MICPT i n the entire sample was 1.5+/-1.4 mm, increased directly with age, and was greater in whites and blacks than Hispanics. Other independent de terminants of MICPT included smoking, glucose, LDL cholesterol, and hy pertension. After we controlled for these covariates, Hispanic (versus non-Hispanic) race-ethnicity was still an in dependent determinant of less carotid plaque. There was a significant interaction between race -ethnicity and LDL cholesterol, with a greater effect of increasing LD L cholesterol among Hispanics. Conclusions Atherosclerotic risk factor s were predictive of MICPT in this mixed-ethnic cohort. Hispanics had significantly less carotid plaque after adjustment for other known ris k factors, but they also had a greater impact of increasing LDL choles terol.