Circulating soluble adhesion molecules ICAM-1 and VCAM-1 and incident coronary heart disease: the PRIME Study

The Epidemiological Study of Myocardial Infarction Study which enrolled 9758 apparently healthy men aged 50-59 years, is a prospective cohort study designed to evaluate markers of coronary risk. Soluble forms of the intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels were measured in plasma obtained at baseline from 317 subjects who suffered a coronary event during the 5-year follow-up and in twice the number of control subjects who were matched for center, age and day of inclusion in a nested case-control design. The relative risk associated with the highest compared with the lowest thirds of ICAM-1 (>625 versus <502 ng/ml) was 2.45 (95% CI: 1.64-3.65, P<0.001) without adjustment; it decreased moderately (RR: 2.09; 95% CI: 1.34-3.24, P<0.001) after control for lipid and non-lipid factors and remained significantly elevated after adjustment for C-reactive protein (CRP) (RR: 1.90; 95% CI: 1.21-2.96, P=0.005). Plasma ICAM-1 was essentially associated with the risk of myocardial infarction or coronary death and also with angina pectoris. Subjects with CRP presented elevated coronary risk only if ICAM-1 was high. An elevated level of VCAM-1 was not associated with any risk of future acute coronary event, or with angina pectoris. This data indicates that plasma levels of ICAM-1 may serve as risk markers for future coronary events whatever their clinical presentation and that risk is better defined using simultaneous measurements of ICAM-1 and CRP than any of these levels separately.