Soluble adhesion molecules and unstable coronary artery disease

Leukocyte adhesion and transendothelial migration, prerequisites in the dev elopment of atherosclerosis, are largely mediated by adhesion molecules. In addition, unstable coronary syndromes usually involve platelet activation and thrombus formation at the site of atherosclerotic plaque. Therefore, we compared plasma levels of soluble P-selectin, a measurement of platelet ac tivation, as well as E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in patients with atheroscle rosis undergoing coronary angiography (n = 76). Soluble P-selectin levels, as measured by ELISA, were significantly elevated in patients with unstable (n = 44) vs stable (n = 32) atherosclerotic disease (73.0 +/- 2.5 ng/ml vs 52.3 +/- 3.0 ng/ml, respectively, P < 0.01). By logistic regression analys is, plasma level of soluble P-selectin was an independent predictor of an u nstable coronary syndrome (OR 4.2, CI 1.4-12.9, P < 0.01). Soluble E-select in level, a marker of endothelial activation, was associated with extent of atherosclerosis but did not correlate with disease stability. Interestingl y, soluble P-selectin was inversely correlated with plasma levels of the an tioxidant alpha -tocopherol (R = -0.443, P < 0.001), a known inhibitor of p latelet function. In summary, amongst the soluble adhesion molecules, only P-selectin is significantly increased in patients with unstable coronary sy ndromes. This study suggests that platelet activation persists in patients with unstable coronary syndromes despite concurrent aspirin therapy. In add ition, the beneficial effects of alpha -tocopherol in patients with cardiov ascular disease may be related to inhibition of platelet function. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.