Abstract 2872: Interleukin-18/interleukin-10 Ratio is an Independent Predictor of Cardiovascular Events in Patients with Stable Coronary Artery Disease

Background: The balance between pro-inflammatory cytokine IL-18 and anti-inflammatory cytokine IL-10 has been suggested to play a role in atherogenesis and in the prognosis of acute coronary syndrome (ACS). We hypothesized that stable coronary artery disease (CAD) patients have a pro-inflammatory profile prior to an acute event. Methods : A case-control study nested in a cohort of stable CAD patients was performed. Patients were consecutively included and blood samples collected at 3-months intervals. Cases were patients who presented any vascular event (death, ACS, ischemic stroke, peripheral arterial occlusion and revascularization) and controls were retrieved from a sequential list, in a 1:2 ratio, after 22 ± 9 months of follow-up. Serum hs-CRP, interleukin (IL)-10, IL-18 were measured in two serial samples, collected before the events. Results : Among 176 CAD patients, 42 developed a vascular event (cases) and 76 were selected to the control group. Serum levels of IL-18 were significantly higher among cases (411 ± 185 vs. 340 ± 133pg/ml; p = 0.037). Hs-CRP levels (5.4 vs. 5.1mg/l), IL-10 (7.4 vs. 7.2pg/ml), and IL-18/IL-10 ratio (66 vs. 61) were not different between cases and controls in both samples. Cox regression analysis showed that IL-18 levels (HR 1.75 (0.89 –3.5;p = 0.11) and IL-18/IL-10 ratio (HR 1.97; 1.0 –3.8) were predictors of worse prognosis (Figure ). Conclusion: In this study, IL-18 and IL-18/IL-10 ratio were associated with clinical outcomes and support the hypothesis that the balance between pro-inflammatory and anti-inflammatory cytokines may be an important determinant of vascular events in stable CAD patients.