Evaluation of serum levels of solubilized adhesion molecules and cytokine receptors in coronary heart disease

OBJECTIVES The diagnostic importance of circulating solubilized tumor necrosis factor-alpha receptor II (sTNF-αRII) and interleukin-2 receptor in coronary heart disease (CHD) was evaluated. In addition, these variables were correlated with solubilized adhesion molecule levels (i.e., intracellular adhesion molecule [ICAM], vascular cell adhesion molecule [VCAM], and E-selectin). BACKGROUND Atherosclerosis is considered to be a chronic inflammatory process. Because the immunologic network presents an abundance of positive and negative feedback mechanisms, information obtained from different immunologic variables might be highly redundant. METHODS In a cross-sectional study design, 60 patients with angiographically proven CHD were compared with 60 individuals who had undergone coronary angiography but in whom no evidence of stenosis could be found (control subjects). Angiography was performed at least one year before the study. Cytokine levels were determined by enzyme-linked immunosorbent assay technique and evaluated by univariate and multivariate statistical methods. RESULTS All immunologic variables except E-selectin (p = 0.08) significantly discriminated between patients and control subjects. Coronary artery bypass graft surgery after angiography did not lead to significant differences in the variables investigated in the patients with bypass surgery as compared with the subjects without bypass surgery. Receiver-operating characteristics analysis showed comparable test accuracy for solubilized adhesion molecules and cytokine receptors. Multivariate logistic regression analysis, including age, revealed that only ICAM and sTNF-αRII were independently correlated with the presence of CHD. Patients belonging to the third tertile of at least one of these two variables demonstrated a 1.6- to 2-fold increased relative risk for the presence of CHD. CONCLUSIONS We concluded that both circulating ICAM and TNF-αRII should be further evaluated as markers for atherosclerotic changes in the coronary system.