Impact of coronary calcium on arterial age and coronary heart disease risk estimation using the MESA arterial age calculator

Abstract

Background We evaluated the impact of arterial age calculation on reclassification of global coronary heart disease risk using the Framingham risk score. Methods We applied CHD risk factor data from the Prospective Army Coronary Calcium Project to the MESA arterial age calculator (available at http://www.mesa-nhlbi.org). Subjects ( N = 1998) were studied with measured CHD risk factors and electron beam computed tomography for the identification of coronary artery calcium. Framingham risk scores (FRS), using the 10-year CHD risk model with and without arterial age, were calculated using the MESA arterial age calculator. Results The mean FRS of the cohort (42.9 ± 2.7 years, male gender 82%) was 4.5 ± 3.6%. Coronary calcium was present in 394 subjects (19.7%). Application of the arterial age calculator increased mean age from 42.9 ± 2.7 to 43.6 ± 10.4 years ( P < .001), and the mean FRS increased from 4.5 ± 3.6 to 7.3 ± 8.1% ( P < .001). Reclassification was seen primarily among male subjects, in whom the mean age (chronological vs. arterial age) increased from 42.9 ± 2.7 to 44.2 ± 11.0 ( P < .001) and the prevalence of high CHD risk increased from 0.6% (10 of 1639) to 10% (165 of 1639; P < .001). Conclusion Among healthy individuals ages 40–50, application of the MESA arterial age calculator reclassifies 1 in 10 men from low to intermediate risk and 1 in 15 men from low to high risk.