title: The prognostic value of troponin in patients with non-ST elevation acute coronary syndromes: a meta-analysis.
abstract: OBJECTIVE
  This study was designed to compare the prognostic value of an abnormal troponin level derived from studies of patients with non-ST elevation acute coronary syndromes (ACS).
  
  
  BACKGROUND
  Risk stratification for patients with suspected ACS is important for determining need for hospitalization and intensity of treatment.
  
  
  METHODS
  We identified clinical trials and cohort studies of consecutive patients with suspected ACS without ST-elevation from 1966 through 1999. We excluded studies limited to patients with acute myocardial infarction and studies not reporting mortality or troponin results.
  
  
  RESULTS
  Seven clinical trials and 19 cohort studies reported data for 5,360 patients with a troponin T test and 6,603 with a troponin I test. Patients with positive troponin (I or T) had significantly higher mortality than those with a negative test (5.2% vs. 1.6%, odds ratio [OR] 3.1). Cohort studies demonstrated a greater difference in mortality between patients with a positive versus negative troponin I (8.4% vs. 0.7%, OR 8.5) than clinical trials (4.8% if positive, 2.1% if negative, OR 2.6, p = 0.01). Prognostic value of a positive troponin T was also slightly greater for cohort studies (11.6% mortality if positive, 1.7% if negative, OR 5.1) than for clinical trials (3.8% if positive, 1.3% if negative, OR 3.0, p = 0.2)
  
  
  CONCLUSIONS
  In patients with non-ST elevation ACS, the short-term odds of death are increased three- to eightfold for patients with an abnormal troponin test. Data from clinical trials suggest a lower prognostic value for troponin than do data from cohort studies.
authors.affiliation: Veterans Affairs Palo Alto Health Care System, California 94304, USA. heiden@stanford.edu
authors.forename: P A
authors.initials: PA
authors.lastname: Heidenreich
authors.forename: T
authors.initials: T
authors.lastname: Alloggiamento
authors.forename: K
authors.initials: K
authors.lastname: Melsop
authors.forename: K M
authors.initials: KM
authors.lastname: McDonald
authors.forename: A S
authors.initials: AS
authors.lastname: Go
authors.forename: M A
authors.initials: MA
authors.lastname: Hlatky
mesh_terms: D000368:Aged; D000789:Angina, Unstable / Q000097:blood / Q000401:mortality; D015415:Biomarkers / Q000097:blood; D002986:Clinical Trials as Topic; D015331:Cohort Studies; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000401:mortality*; D017202:Myocardial Ischemia / Q000097:blood / Q000401:mortality*; D011379:Prognosis; D013577:Syndrome; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T