title: Interleukin-1 receptor antagonist: a sensitive marker of instability in patients with coronary artery disease.
abstract: BACKGROUND
  Increased plasma levels of acute phase reactants are correlated with acute coronary syndromes and increased risk of in-hospital events. Interleukin-1 receptor antagonist (IL-1Ra) modulates the activity of IL-1, a cytokine associated with inflammatory response; we have prospectively investigated whether detection of increased levels of IL-1Ra in patients may be useful in the characterization of coronary syndromes.
  
  
  METHODS
  Plasma levels of IL-1Ra were measured in 118 consecutive patients undergoing coronary angiography with a clinical diagnosis of recent unstable angina (N = 57), chronic stable angina (N = 49) or atypical chest pain (N = 12).
  
  
  RESULTS
  Angiography showed significant coronary disease in the first two groups and was normal in the latter group. Patients with unstable angina had significantly higher levels of IL-1Ra than stable patients [158 (110-224) vs 108 (95-154) pg/ml, P = 0.002] and individuals with chest pain and normal coronary angiogram [110 (97-123) pg/ml, P: = 0.038]. In contrast, while C-reactive protein levels were significantly higher in patients with stable and unstable angina vs those without coronary disease (0.29 vs 0.06 mg/dl, P: = 0.022), they did not discriminate between stable and unstable angina patients (0.22 vs 0.32 mg/dl, P: = 0.66).
  
  
  CONCLUSIONS
  These results indicate that IL-1Ra may be a sensitive marker of clinical instability in patients with coronary artery disease.
authors.affiliation: Department of Cardiovascular Sciences, Campus Bio-Medico University, Rome, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Patti
authors.forename: Andrea
authors.initials: A
authors.lastname: D'Ambrosio
authors.forename: Aldo
authors.initials: A
authors.lastname: Dobrina
authors.forename: Giordano
authors.initials: G
authors.lastname: Dicuonzo
authors.forename: Carlo
authors.initials: C
authors.lastname: Giansante
authors.forename: Nicola
authors.initials: N
authors.lastname: Fiotti
authors.forename: Antonio
authors.initials: A
authors.lastname: Abbate
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Guarnieri
authors.forename: Germano
authors.initials: G
authors.lastname: Di Sciascio
mesh_terms: D000368:Aged; D000789:Angina, Unstable / Q000097:blood; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D003324:Coronary Artery Disease / Q000097:blood*; D005260:Female; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D008297:Male; D008875:Middle Aged; D012795:Sialoglycoproteins / Q000097:blood*; D018709:Statistics, Nonparametric
chemical_list: D015415:Biomarkers; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D012795:Sialoglycoproteins