title: Do major cardiovascular outcomes in patients with stable ischemic heart disease in the clinical outcomes utilizing revascularization and aggressive drug evaluation trial differ by healthcare system?
abstract: BACKGROUND
  The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial enrolled patients from 3 distinct healthcare systems (HCSs) in North America. The primary aim of this study was to determine whether there is a treatment difference in cardiovascular outcomes by HCS.
  
  
  RESULTS
  The study population included 968 patients from the US Department of Veterans Affairs (VA), 386 from the US non-VA, and 931 from Canada with different comorbidities and prognoses. The primary outcome was all-cause mortality or nonfatal myocardial infarction (MI) during the median 4.6-year follow-up. Baseline demographics were similar between percutaneous coronary intervention and optimal medical therapy treatment groups within each HCS. After follow-up, the primary end point of total mortality and nonfatal MI was not statistically significant between percutaneous coronary intervention and optimal medical therapy, regardless of HCS: VA, 22.3% versus 21.9% (hazard ratio, 1.05; 95% CI, 0.80-1.38; P=0.95); US non-VA, 15.8% versus 21.8% (hazard ratio, 0.70; 95% CI, 0.43-1.12; P=0.24); Canadian HCS, 17.3% versus 13.5% (hazard ratio, 1.30; 95% CI, 0.93-1.83; P=0.17). The interaction between HCSs and treatment was not statistically significant. Long-term mortality was significantly higher in the VA system as a result of significantly greater comorbidity and worse left ventricular function.
  
  
  CONCLUSIONS
  In the COURAGE trial, addition of percutaneous coronary intervention to optimal medical therapy did not improve 5-year survival or reduce MI or other major adverse cardiovascular events regardless of whether patients were Canadian or American or US veterans or non-veterans. Outcome differences were largely explained by differences in baseline characteristics known to affect long-term prognosis.
authors.affiliation: Department of Internal Medicine, Saint Louis University School of Medicine, 1034 S Brentwood Blvd., St Louis, MO 63117, USA. chaitman@slu.edu
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Chaitman
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Hartigan
authors.forename: David C
authors.initials: DC
authors.lastname: Booth
authors.forename: Koon K
authors.initials: KK
authors.lastname: Teo
authors.forename: G B John
authors.initials: GB
authors.lastname: Mancini
authors.forename: William J
authors.initials: WJ
authors.lastname: Kostuk
authors.forename: John A
authors.initials: JA
authors.lastname: Spertus
authors.forename: David J
authors.initials: DJ
authors.lastname: Maron
authors.forename: Marcin
authors.initials: M
authors.lastname: Dada
authors.forename: Robert A
authors.initials: RA
authors.lastname: O'Rourke
authors.forename: William S
authors.initials: WS
authors.lastname: Weintraub
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Berman
authors.forename: Leslee J
authors.initials: LJ
authors.lastname: Shaw
authors.forename: William E
authors.initials: WE
authors.lastname: Boden
mesh_terms: D002170:Canada; D015897:Comorbidity; D003695:Delivery of Health Care / Q000706:statistics & numerical data*; D018450:Disease Progression; D004358:Drug Therapy / Q000379:methods / Q000401:mortality; D005500:Follow-Up Studies; D006801:Humans; D009203:Myocardial Infarction; D017202:Myocardial Ischemia / Q000453:epidemiology* / Q000503:physiopathology / Q000628:therapy; D009204:Myocardial Revascularization / Q000379:methods / Q000401:mortality; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States; D018487:Ventricular Dysfunction, Left / Q000453:epidemiology* / Q000503:physiopathology / Q000628:therapy; D014728:Veterans