Abstract 6200: Ethnic Differences in Carotid Artery Distensibility: Multi-Ethnic Study of Atherosclerosis
When African-Americans are compared to Whites, there is a greater incidence of diseases associated with stiffer arteries, including hypertension, stroke and heart failure. There is a paucity of data regarding ethnic differences in arterial stiffness, particularly in persons without known cardiovascular disease. We therefore examined arterial distensibility in the Multi-ethnic Study of Atherosclerosis (MESA). At MESA baseline (2000–2002), 6358 Americans without clinical cardiovascular disease of White (W, 38%), Chinese (C, 12%), African (A, 27%), and Hispanic (H, 22%) ethnicities had carotid diameter measurements by ultrasound and brachial blood pressure measurements during systole and diastole. We estimated carotid distensibility as the slope of the arterial diameter versus pressure in mixed model analysis where each individual’s intercept (carotid diameter at the brachial arterial pressure of 100mmHg) and slope were modeled as random effects. Sex-stratified models were adjusted for age, antihypertensive use, and metabolic variables (see table footnote). The table⇓ shows the intercept and distensibility in women and men of different ethnicities. Compared to men, women have smaller diameter and less distensible vessels (both p<0.001). There is ethnic heterogeneity for the diameter intercept (women p<0.001, men p=0.002), and distensibility (both p<0.001). C women have significantly larger carotid diameter than all other ethnicities. W and C men have larger diameter as compared to B and H men. However, W women and W men have greater distensibility than all other ethnicities. In our study, compared with Whites, African-Americans have lower arterial distensibility, which may contribute to greater cardiovascular morbidity and mortality. Lower arterial distensibility in Chinese and Hispanic Americans is a novel finding and would support further study of vascular disease incidence and its prevention in these ethnicities.