17. Carotid Intima-Media Thickness in a Large Cohort Study and Really Normal Subjects

Abstract

Background

Carotid intima-media thickness (IMT) has been widely used as a surrogate of early atherosclerosis. However, the characteristics of patients in cohort-based studies of carotid IMT are very heterogeneous. We evaluated the carotid intima, media, and IMT in really normal (RN) subjects who had no coronary artery disease or other coronary risk factors.

Methods

Among the 3041 patients (male:female = 1819:1222, mean age = 61 ± 11 years) who have undergone carotid ultrasound at our institution since 2003,124 patients (male:female = 84:40, mean age 54 ± 12 years) who had no coronary artery stenosis confirmed by coronary angiography and no diabetes, hypertension, hypercholesterolemia, or renal dysfunction were enrolled in this study. The carotid intima, media, and IMT were compared between the general population group and the RN subjects.

Results

Right maximal, mean IMT, intimal thickness, and medial thickness were 0.93 ± 0.25, 0.78 ± 0.16, 0.24 ± 0.36, and 0.51 ± 0.15mm in RN subjects, respectively. The left maximal, mean IMT, intimal thickness, and medial thickness were 0.92 ± 0.33, 0.79 ± 0.24, 0.23 ± 0.03, and 0.55 ± 0.24 mm, respectively. The maximal and mean IMT and medial thickness of both carotid arteries were significantly higher in subjects from the general population.

Conclusion

In a large Korean cohort for carotid IMT, the carotid medial thickness and IMT were significantly related to atherosclerotic risk factors. We must be careful in defining the normal reference values of carotid IMT due to heterogeneous characteristics in the population.