Objectives: To assess how ultrasound measurements of carotid intima-media thickness (CIMT) and plaque burden compare with the Framingham Risk Score (FRS) in a clinical setting.
Methods and results: In a cross-sectional study, we determined CIMT and plaque in 409 asymptomatic, non-diabetic hyperlipidemic subjects (242 men, age 49+/-11 years) who were assessed for risk factors and classified into FRS categories: 10-year risk < or =5% (n=191), 6-20% (n=176), and >20% (n=42). Percentiles of CIMT and plaque height and regression equations of CIMT against age obtained in 250 controls subjects were used to define atherosclerosis and estimate vascular age, respectively. There was a wide dispersion of CIMT for each FRS category. CIMT values were discordant in 242 (59%) subjects, 80% of them showing more atherosclerosis than predicted. Smoking and the metabolic syndrome explained part of the discrepancies in the intermediate-risk group. Triglycerides, homocysteine, and lipoprotein(a) did not predict atherosclerotic burden. Mean vascular age was 14.5 years older than chronological age.
Conclusions: Carotid atherosclerosis findings readjust FRS categories in many asymptomatic subjects. Both carotid atherosclerotic burden and vascular age may be used to refine CHD risk and tailor preventive treatment beyond the FRS.