P1-76 INTERLEUKIN-18: A STRONG PREDICTOR OF THE EXTENT OF CORONARY ARTERY DISEASE IN PATIENTS WITH UNSTABLE ANGINA

Abstract

The aim of this study was to confirm that plasma interleukin (IL)-18 level is associated with the extent of coronary artery disease in unstable angina patients. Previous studies have shown that patients with unstable angina have significantly higher plasma IL-18 levels than healthy volunteers. However, the association between IL-18 and the extent of coronary artery atherosclerosis in patients with unstable angina remains unclear. Plasma concentrations of IL-18 and high-sensitivity C-reactive protein (hs-CRP) were measured in 166 consecutive patients admitted for coronary arteriography. One hundred and eighteen patients with unstable angina had coronary artery disease (coronary artery disease group; severity score: 2.32 ± 1.47; Gensini score: 31.3 ± 25.9), and 48 patients with coronary risk factors and without coronary artery lesions served as the risk control group. Plasma levels of IL-18 were higher in the coronary artery disease group than in the risk control group (P = 0.062). Additionally, plasma levels of IL-18 were significantly higher in 77 coronary artery disease patients with severity score ≥2 than in the risk control group (242.3 ± 110.6 vs 209.8 ± 120.3 pg/ml, P = 0.016). By univariate analysis, log-transformed plasma IL-18 concentration was positively correlated with coronary artery disease severity score (r = 0.244, P = 0.009). By multiple regression analyses, the association between coronary artery disease severity score and IL-18 remained significant (β = 0.733, P = 0.017) when controlling for age, diabetes mellitus and left ventricular ejection fraction. Additionally, coronary artery disease severity score was greater in the highest tertile (>246 pg/ml) of plasma IL-18 levels than in the middle (176–246 pg/ml) and the lowest (<176 pg/ml) tertiles (2.79 ± 1.52 vs 2.05 ± 1.08 vs 2.13 ± 1.66, P = 0.028). Of note, plasma hs-CRP level had no significant correlation with coronary artery severity. Plasma IL-18 level is associated with the extent of coronary artery disease in unstable angina patients, suggesting the link between IL-18 and coronary artery atherosclerosis in these patients.