The relationship between carotid intima-media thickness and carotid plaque: a cohort study in China

Both carotid intima-media thickness (cIMT) and carotid plaque (CP) quantified by B-mode ultrasound have been proposed as surrogate imaging biomarkers of subclinical atherosclerosis, while the relationship between cIMT and CP, whether cIMT evaluation in a given patient might allow for predicting the development of a carotid plaque, is still discussed controversially. We investigated the cross-sectional relationship between cIMT and CP, and the predictive value of cIMT for incident CP formation in 1078 subjects with mean age of 52 +/- 5 years in a community based atherosclerosis cohort in Beijing. Participants underwent ultrasonography of bilateral carotid arteries and received vascular risk factor assessment at baseline and after a mean of 2.35 years follow-up. The prevalence of plaque was increased by 3.75-fold for upper quartile cIMT compare with the lower quartile even after adjustments for traditional risk factors at baseline. Among the 746 plaque-free subjects at baseline, 230 (31.0%) developed new CP. After adjusted for demographics and vascular risk factors, neither baseline cIMT nor the cIMT change from baseline to follow-up predicted incident CP. In conclusion, although cIMT associates with CP cross-sectionally, increased cIMT dose not independently predict future plaque development. Our data suggest that paying attention to the traditional risk factors might prevent subjects from developing carotid plaques regardless from IMT changes.