Correlates of Common Carotid Artery Lumen Diameter in Black and White Younger Adults

Background and Purpose—Vascular remodeling as depicted by increases in arterial lumen diameter occurs in response to development of atherosclerosis. However, data on the correlates of arterial lumen diameter in younger adults by race and sex are limited. Methods—The study cohort included 734 white and 306 black subjects, aged 20 to 43 years, enrolled in the Bogalusa Heart Study. The common carotid artery lumen diameter at diastole and intima media thickness (IMT) were measured by Mand B-mode ultrasonography, respectively. Results—As a group, blacks versus whites (3.44 mm/m versus 3.37 mm/m, P 0.002) and males versus females (3.45 mm/m versus 3.35 mm/m, P 0.001) had greater height-adjusted lumen diameter. In multivariate analyses of total sample, body mass index, mean arterial pressure, heart rate, and carotid IMT were independent predictors of height-adjusted lumen diameter. The magnitude of the effects of mean arterial pressure and carotid IMT on height-adjusted lumen diameter was significantly different between races with blacks showing greater slopes (difference in slopes: P 0.011 for mean arterial pressure; P 0.033 for IMT); interaction effects of body mass index and mean arterial pressure with sex on height-adjusted lumen diameter were also noted with males showing steeper slopes (difference in slopes: P 0.003 for body mass index; P 0.005 for mean arterial pressure). In addition, the lumen diameter–carotid IMT relationship was stronger in hypertensives than in normotensives (difference in slopes: P 0.038). Conclusions—Common carotid artery lumen diameter is influenced by carotid artery IMT, adiposity, and blood pressure in a raceand sex-specific manner in asymptomatic younger adults, which may have implications for preventive cardiology. (Stroke. 2009;40:702-707.)