Correlation between carotid intima-media roughness and cardiovascular risk factors

Arterial intima-media roughness (IMR) may indicate an early manifestation of atherosclerosis. To date, few studies have been performed to quantitatively evaluate carotid IMR by ultrasonography (US). The aim of the present study was to analyze the effect of cardiovascular risk factors on carotid IMR. A total of 185 subjects were enrolled for US examination of carotid arteries. Carotid intima-media thickness (IMT) and IMR were measured in US images by a novel automatic software. According to the number of combined high-risk factors for coronary heart disease, subjects were assigned to four groups (risk groups 0, 1, 2 and 3+). IMR was lowest in risk group 0 (32.9±2.7 µm), higher in risk group 1 (64.5±6.9 µm; P<0.01 vs. risk group 0) and highest in risk groups 2 and 3+ (89.1±7.4 and 92.0±6.7 µm, respectively; P<0.01 vs. risk groups 0 and 1). According to a multivariate regression analysis, age, systolic blood pressure, smoking status and the triglyceride/high-density lipoprotein cholesterol ratio were significant predictors of IMR. There was a progressive increase in carotid artery plaque with increasing tertiles of IMR (4.9, 33.9 and 53.2% in tertiles 1, 2 and 3, respectively; P<0.05). Compared with that of subjects in the lowest tertile of IMR, those in the highest tertile had a significantly elevated risk of the presence of plaque in the carotid tree (odds ratio=10.61, 95%CI: 2.15-52.49, P=0.004). Quantification of carotid IMR from US images with this software is feasible, and carotid IMR, which may help estimate the extent of atherosclerosis, may be used as a complementary factor to stratify patients with cardiovascular risk factors.