title: A systematic review and meta-analysis on the hazards of discontinuing or not adhering to aspirin among 50,279 patients at risk for coronary artery disease.
abstract: OBJECTIVE
  The role of aspirin in patients with coronary artery disease (CAD) is well established, yet patients happen to discontinue aspirin according to physician's advice or unsupervised. We thus undertook a systematic review to appraise the hazards inherent to aspirin withdrawal or non-compliance in subjects at risk for or with CAD.
  
  
  RESULTS
  Electronic databases were systematically searched (updated January 2006). Study designs, patient characteristics, and outcomes were abstracted. Pooled estimates for odds ratios (OR) were computed according to random-effect methods. From the 612 screened studies, six were selected (50,279 patients). One study (31,750 patients) focused on adherence to aspirin therapy in the secondary prevention of CAD, two studies (2594) on aspirin discontinuation in acute CAD, two studies (13,706) on adherence to aspirin therapy before or shortly after coronary artery bypass grafting, and another (2229) on aspirin discontinuation among patients undergoing drug-eluting stenting. Overall, aspirin non-adherence/withdrawal was associated with three-fold higher risk of major adverse cardiac events (OR=3.14 [1.75-5.61], P=0.0001). This risk was magnified in patients with intracoronary stents, as discontinuation of antiplatelet treatment was associated with an even higher risk of adverse events (OR=89.78 [29.90-269.60]).
  
  
  CONCLUSIONS
  Non-compliance or withdrawal of aspirin treatment has ominous prognostic implication in subjects with or at moderate-to-high risk for CAD. Aspirin discontinuation in such patients should be advocated only when bleeding risk clearly overwhelms that of atherothrombotic events.
authors.affiliation: Interventional Cardiology, Division of Cardiology, University of Turin, corso Bramante 88-90, 10126 Turin, Italy. gbiondizoccai@gmail.com
authors.forename: Giuseppe G L
authors.initials: GG
authors.lastname: Biondi-Zoccai
authors.forename: Marzia
authors.initials: M
authors.lastname: Lotrionte
authors.forename: Pierfrancesco
authors.initials: P
authors.lastname: Agostoni
authors.forename: Antonio
authors.initials: A
authors.lastname: Abbate
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Fusaro
authors.forename: Francesco
authors.initials: F
authors.lastname: Burzotta
authors.forename: Luca
authors.initials: L
authors.lastname: Testa
authors.forename: Imad
authors.initials: I
authors.lastname: Sheiban
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sangiorgi
mesh_terms: D001241:Aspirin / Q000627:therapeutic use*; D003324:Coronary Artery Disease / Q000188:drug therapy*; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D016312:Treatment Refusal
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin