Interleukin-1 receptor antagonist: a sensitive marker of instability in patients with coronary artery disease.

Elevated plasma levels of inflammatory markers, such as C-reactive protein (CRP), have been associated with adverse outcome in selected patients with coronary artery disease (CAD) treated with coronary angioplasty or stenting. The aim of this study was to evaluate the predictive value of preprocedural interleukin-1 receptor antagonist (IL-1Ra) plasma levels for long-term major adverse cardiac events (MACE) in a series of unselected patients with symptomatic CAD treated with percutaneous coronary intervention (PCI). Seventy-three consecutive patients (62 men, aged 62 +/- 9 years) undergoing PCI were enrolled in a prospective follow-up study. IL-1Ra and CRP plasma levels were measured before the procedure; 36 patients (49%) had unstable angina pectoris on admission, 37 (51%) had chronic stable angina pectoris, and 30 (41%) had multivessel CAD, 15 of whom underwent multivessel PCI. Success was achieved in all 73 patients, with coronary stenting performed in 63 (86%). Follow-up clinical assessment included occurrence of MACE at 3, 6, 12, and 18 months. Logistic regression analysis, performed to determine independent predictors of MACE, identified IL-1Ra levels in the upper quartile as the only independent predictive factor of MACE at 18 months (19% in the fourth quartile vs 0% in the first quartile; p = 0.032). Patients with high preprocedural CRP levels (fourth quartile) had a nonsignificant increased risk of MACE (p = 0.09). Thus, preprocedural IL-1Ra plasma levels appear to be a valuable independent predictive factor of MACE in unselected patients undergoing PCI.