title: Outcomes According to Cardiac Catheterization Referral and Clopidogrel Use Among Medicare Patients With Non-ST-Segment Elevation Myocardial Infarction Discharged Without In-hospital Revascularization.
abstract: BACKGROUND
  While use of P2Y12 receptor inhibitor is recommended by guidelines, few studies have examined its effectiveness among older non-ST-segment elevation myocardial infarction patients who did not undergo coronary revascularization.
  
  
  RESULTS
  We included unrevascularized non-ST-segment elevation myocardial infarction patients ≥65 years discharged home from 463 ACTION Registry-GWTG hospitals from 2007 to 2010. Rates of discharge clopidogrel use were described for patients with no angiography, angiography without obstructive coronary artery disease (CAD; ≥50% stenosis in ≥1 vessel), and angiography with obstructive CAD. Two-year outcomes were ascertained from linked Medicare data and included composite major adverse cardiac events (defined as all-cause death, myocardial infarction readmission, or revascularization), and individual components. Outcomes associated with clopidogrel use were adjusted using inverse probability-weighted propensity modeling. Of 14 154 unrevascularized patients, 54.7% (n=7745) did not undergo angiography, 10.6% (n=1494) had angiography without CAD, and 34.7% (n=4915) had angiography with CAD. Discharge clopidogrel was prescribed for 42.2% of all unrevascularized patients: 37.8% without angiography, 34.1% without obstructive CAD at angiography, and 51.6% with obstructive CAD at angiography. Discharge clopidogrel use was not associated with major adverse cardiac events in any group: without angiography (adjusted hazard ratio [95% CI]: 0.99 [0.93-1.06]), angiography without CAD (1.04 [0.74-1.47]), and angiography with CAD (1.12 [1.00-1.25], Pinteraction=0.20).
  
  
  CONCLUSIONS
  We found no association between discharge clopidogrel use and long-term risk of major adverse cardiac events among older, unrevascularized non-ST-segment elevation myocardial infarction patients. Clopidogrel use in this population requires further prospective evaluation.
authors.affiliation: University of Colorado School of Medicine, Aurora, CO connie.hess@ucdenver.edu.
authors.forename: Connie N
authors.initials: CN
authors.lastname: Hess
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Anne S
authors.initials: AS
authors.lastname: Hellkamp
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Roe
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Laine
authors.initials: L
authors.lastname: Thomas
authors.affiliation: Brigham and Women's Hospital, Boston, MA.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Scirica
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: S Andrew
authors.initials: SA
authors.lastname: Peng
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.affiliation: Duke Clinical Research Institute, Durham, NC.
authors.forename: Tracy Y
authors.initials: TY
authors.lastname: Wang
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006328:Cardiac Catheterization; D000077144:Clopidogrel; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D006278:Medicare; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000188:drug therapy*; D009204:Myocardial Revascularization; D010351:Patient Discharge; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D058921:Purinergic P2Y Receptor Antagonists / Q000627:therapeutic use*; D012017:Referral and Consultation; D012042:Registries; D012307:Risk Factors; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
chemical_list: D010975:Platelet Aggregation Inhibitors; D058921:Purinergic P2Y Receptor Antagonists; D000077144:Clopidogrel; D013988:Ticlopidine
keywords: P2Y12 receptor inhibitor; effectiveness; unrevascularized non–ST‐segment elevation myocardial infarction patients