Predictors of Carotid Thickness and Plaque Progression During a Decade

Abstract

Background and Purpose— Carotid artery intima-media thickness (IMT) and plaque are noninvasive markers of subclinical arterial injury that predict incident cardiovascular disease. We evaluated predictors of longitudinal changes in IMT and new plaque during a decade in a longitudinal multiethnic cohort. Methods— Carotid IMT and plaque were evaluated in Multi-Ethnic Study of Atherosclerosis (MESA) participants at exams 1 and 5, a mean (standard deviation) of 9.4 (0.5) years later. Far wall carotid IMT was measured in both common and internal carotid arteries. A plaque score was calculated from all carotid segments. Mixed-effects longitudinal and multivariate regression models evaluated associations of baseline risk factors and time-updated medication use with IMT progression and plaque formation. Results— The 3441 MESA participants were aged 60.3 (9.4) years (53% women; 26% blacks, 22% Hispanic, 13% Chinese); 1620 (47%) had carotid plaque. Mean common carotid artery IMT progression was 11.8 (12.8) μm/year, and 1923 (56%) subjects developed new plaque. IMT progressed more slowly in Chinese (β=−2.89; P =0.001) and Hispanic participants (β=−1.81; P =0.02), and with higher baseline high-density lipoprotein cholesterol (per 5 mg/dL; β=−0.22; P =0.03), antihypertensive use (β=−2.06; P =0.0004), and time on antihypertensive medications (years; β=−0.29; P <0.0001). Traditional risk factors were associated with new plaque formation, with strong associations for cigarette use (odds ratio, 2.31; P <0.0001) and protection by black ethnicity (odds ratio, 0.68; P <0.0001). Conclusions— In a large, multiethnic cohort with a decade of follow-up, ethnicity was a strong, independent predictor of carotid IMT and plaque progression. Antihypertensive medication use was associated with less subclinical disease progression.