title: Dual Antiplatelet Therapy Versus Aspirin Monotherapy in Diabetics With Multivessel Disease Undergoing CABG: FREEDOM Insights.
abstract: BACKGROUND
  Clinical practice guidelines recommend post-operative dual antiplatelet therapy (DAPT) in patients who undergo coronary artery bypass grafting (CABG) following acute coronary syndromes (ACS).
  
  
  OBJECTIVE
  The authors have evaluated DAPT utilization rates and associated outcomes among post-CABG patients with diabetes.
  
  
  METHODS
  In a post hoc, nonrandomized analysis from the FREEDOM (Future REvascularization Evaluation in patients with Diabetes mellitus: Optimal management of Multivessel disease) trial, we compared patients receiving DAPT (aspirin plus thienopyridine) and aspirin monotherapy at 30 days post-operatively. The primary outcome was the risk adjusted 5-year FREEDOM composite of all-cause mortality, nonfatal myocardial infarction, or stroke. Safety outcomes included major bleeding, blood transfusion, and hospitalization for bleeding.
  
  
  RESULTS
  At 30 days post-CABG, 544 (68.4%) patients received DAPT and 251 (31.6%) patients received aspirin alone. The median (25th, 75th percentile) duration of clopidogrel therapy was 0.98 (0.23 to 1.91) years. There was no significant difference in the 5-year primary composite outcome between DAPT- and aspirin-treated patients (12.6% vs. 16.0%; adjusted hazard ratio [HR]: 0.83; 95% confidence interval [CI]: 0.54 to 1.27; p = 0.39). The 5-year primary composite outcomes were similar for patients receiving DAPT versus aspirin monotherapy respectively, in subgroups with pre-CABG ACSs (15.2% vs. 16.5%; HR: 1.06; 95% CI: 0.53 to 2.10; p = 0.88) and those with stable angina (11.6% vs. 15.8%; HR: 0.82; 95% CI: 0.50 to 1.343; p = 0.42). The composite outcomes of both treatment groups were also similar by SYNTAX score, duration of DAPT therapy, completeness of revascularization, and in off-pump CABG. No treatment-related differences in major bleeding (5.6% vs. 5.7%; HR: 1.00; 95% CI: 0.50 to 1.99; p = 0.99), blood transfusions (4.8% vs. 4.5%; HR: 1.09; 95% CI: 0.51 to 2.34; p = 0.82), or hospitalization for bleeding (2.6% vs. 3.3%; HR: 0.85; 95% CI: 0.34 to 2.17; p = 0.74) were observed between aspirin- and DAPT-treated patients, respectively.
  
  
  CONCLUSIONS
  The use of DAPT in patients with diabetes post-CABG in our cohort was high. Compared with aspirin monotherapy, no associated differences were observed in cardiovascular or bleeding outcomes, suggesting that routine use of DAPT may not be clinically warranted. (Future REvascularization Evaluation in patients with Diabetes mellitus: Optimal management of Multivessel disease [FREEDOM]; NCT00086450).
authors.affiliation: Department of Critical Care and Division of Cardiology, University of Alberta, Edmonton, Alberta, Canada; Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada. Electronic address: sv9@ualberta.ca.
authors.forename: Sean
authors.initials: S
authors.lastname: van Diepen
authors.affiliation: Icahn School of Medicine at Mount Sinai, New York, New York.
authors.forename: Valentin
authors.initials: V
authors.lastname: Fuster
authors.affiliation: Division of Cardiac Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Subodh
authors.initials: S
authors.lastname: Verma
authors.affiliation: New England Research Institutes, Inc., Watertown, Massachusetts.
authors.forename: Taye H
authors.initials: TH
authors.lastname: Hamza
authors.affiliation: New England Research Institutes, Inc., Watertown, Massachusetts.
authors.forename: F Sandra
authors.initials: FS
authors.lastname: Siami
authors.affiliation: Canadian VIGOUR Centre, University of Alberta, Edmonton, Alberta, Canada; Terrence Donnelly Heart Centre, Division of Cardiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Shaun G
authors.initials: SG
authors.lastname: Goodman
authors.affiliation: Peter Munk Cardiac Centre and the Heart and Stroke Richard Lewar Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Farkouh
mesh_terms: D054058:Acute Coronary Syndrome / Q000401:mortality / Q000601:surgery*; D000368:Aged; D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use*; D002423:Cause of Death; D000077144:Clopidogrel; D003925:Diabetic Angiopathies / Q000401:mortality / Q000601:surgery*; D004359:Drug Therapy, Combination; D004363:Drug Utilization; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality / Q000517:prevention & control; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D011182:Postoperative Care; D011183:Postoperative Complications / Q000188:drug therapy* / Q000401:mortality; D016016:Proportional Hazards Models; D020521:Stroke / Q000401:mortality / Q000517:prevention & control; D015996:Survival Rate; D013988:Ticlopidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin
keywords: antiplatelet therapy; aspirin; clopidogrel; coronary artery bypass grafting