Interleukin-18 levels on admission are associated with mid-term adverse clinical events in patients with ST-segment elevation acute myocardial infarction undergoing percutaneous coronary intervention.

The long-term prognostic value of interleukin (IL)-18 in patients with ST-segment elevation acute myocardial infarction (STEMI) has been conflicting. Thus, the purpose of this study was to test whether the level of interleukin-18 measured on admission can predict long-term adverse clinical events in patients with STEMI who were undergoing percutaneous coronary intervention (PCI). We recruited 288 consecutive STEMI patients (210 men, average age [71.42 +/- 10.32] years) with onset < 6 hours who were undergoing primary PCI, and 148 age- and gender-matched control subjects. Plasma levels of IL-18 were measured by enzyme-linked immunosorbent assay (ELISA) in all subjects. The patients with STEMI were then followed prospectively over 434 days (range, 0 to 642 days) for the occurrence of composite major adverse clinical events (MACE) (cardiac mortality, recurrent myocardial infarction, or readmission due to advanced heart failure). Patients with STEMI exhibited higher levels of plasma IL-18 (P < 0.001) compared with the control subjects. Positive correlations between IL-18 and cardiac troponin-I (cTnI) (r = 0.353, P = 0.0004) and IL-18 and high-sensitivity C-reactive protein (hs-CRP) (r = 0.420, P < 0.001) were observed by Spearman's correlations analysis. Logistic regression analysis demonstrated that IL-18 >/= 450 pg/mL (OR 10.854, 95% CI 2.328 to 50.594, P < 0.0001) was a significant independent predictor of composite MACE at 60 days. Cox regression analysis demonstrated that high plasma IL-18 levels were not correlated with the occurrence of long-term composite MACE. The level of plasma IL-18 on admission may predict 60-day adverse clinical outcome, but not the long-term adverse clinical events in patients with STEMI undergoing PCI, and may be useful for mid-term risk stratification.