Improvement in the estimation of cardiovascular risk by carotid intima-medial thickness: A report from the Dublin Cardiohealth station study

BACKGROUND The 5th Joint Task Force European guidelines on cardiovascular disease (CVD) prevention recommend the measurement of carotid intima-media thickness (CIMT) in asymptomatic individuals at moderate risk (Class IIa). We aimed to evaluate the ability of CIMT to further risk stratify patients. DESIGN Cross-sectional study. METHODS Patients aged over 18 years free of known CVD at moderate, high, or very high risk of CVD were included. The Panasonic Cardiohealth station, a semi-automated ultrasound system, was used to detect carotid plaque and measure CIMT. Elevated CIMT was defined as =/> 0.9 mm. We analyzed the percentage of those at moderate risk reclassified after addition of CIMT. RESULTS Two hundred patients were included (55% women, mean age 57 years, 12% diabetic); 64%, 23% and 13% were classified as moderate, high, and very high risk, respectively. Across these risk categories, 17%, 33%, and 46% had elevated IMT, p for trend < 0.001. With the addition of CIMT, 13.9% (95% CI: 5.7% to 22.1%) of women and 20.4% (95% CI: 8.7% to 32.1%) of men initially moderate risk were reclassified. CONCLUSIONS CIMT measurement reclassifies a considerable percentage of those at moderate risk based on traditional risk factors alone.