Circulating ICAM-1 (intercellular Cell-adhesion Molecule 1) is Associated with Early Stages of Atherosclerosis Development and with Inflammatory Cytokines in Healthy 58-year-old Men: the Atherosclerosis and Insulin Resistance (AIR) Study

There is a lack of data on circulating levels of cell-adhesion molecules in relation to subclinical atherosclerosis measured in both the carotid and femoral arteries in humans. The aim of the present study was to investigate the relationship between clinically silent atherosclerosis and cell-adhesion molecules, and to explore the relationship between these molecules, C-reactive protein and the inflammatory cytokines interleukin-6, tumour necrosis factor-alpha (TNF-alpha), soluble TNF-alpha receptor p55 and soluble TNF-alpha receptor p75. The study group (n=391) consisted of clinically healthy 58-year-old men recruited from the general population. The results showed a positive trend between levels of soluble intercellular cell-adhesion molecule 1 (sICAM-1) and plaque occurrence in the carotid and femoral arteries (P=0.008), and also a univariate correlation between sICAM-1 levels and the composite variable of carotid and femoral intima-media thickness (P<0.001). When adjusted for other risk factors, the relationship between sICAM-1 and intima-media thickness no longer reached statistical significance. The level of sICAM-1 was associated with those of the pro-inflammatory cytokine TNF-alpha, its two soluble receptors, and also interleukin-6 and C-reactive protein. Levels of soluble E-selectin and vascular cell-adhesion molecule 1 (VCAM-1) showed weak or no association with subclinical atherosclerosis and inflammatory variables. Thus, in clinically healthy middle-aged men, levels of sICAM-1, but not of soluble VCAM-1 or E-selectin, were associated with both subclinical atherosclerosis and inflammatory variables.