title: Contemporary Trends in Oral Antiplatelet Agent Use in Patients Treated with Percutaneous Coronary Intervention for Acute Coronary Syndrome.
abstract: BACKGROUND
  Recent trials demonstrated the efficacy of prasugrel and ticagrelor compared with clopidogrel in the reduction of cardiovascular complications in patients with acute coronary syndrome (ACS). However, it is unclear how use of the 3 antiplatelet medications has changed in commercially insured patients since the advent of the new agents.
  
  
  OBJECTIVE
  To (a) describe the adoption of prasugrel and ticagrelor in patients who received percutaneous coronary intervention (PCI) for the onset of ACS and (b) explore patient factors associated with the selection of the drug to provide insight into utilization patterns of these antiplatelet agents.
  
  
  METHODS
  Patients who received a new dispensing of an antiplatelet agent following a hospitalization for a PCI administered for ACS were identified from insurance claims between 2009 and 2013. Demographics and comorbid conditions were determined based on a 6-month period before the ACS event. Longitudinal trends in antiplatelet agent selection were illustrated using descriptive statistics segmented by month and quarter. Using logistic regressions with stepwise model selection, factors associated with use of the newer medications, as well as with the selection between ticagrelor and prasugrel, were identified.
  
  
  RESULTS
  The analysis included 66,335 subjects. The use of clopidogrel decreased from 100% to roughly 65% of total antiplatelet agent use by the end of 2011 and leveled off thereafter. The introduction of ticagrelor in 2011 coincided with a drop in prasugrel initiation from 35%-18% by December 2013. The use of new agents as opposed to use of clopidogrel was associated with younger age (< 65 years), male gender, and a diagnosis of ST-elevation myocardial infarction. In addition, conditions increasing mortality and risk of cardiovascular complication were associated with higher odds of using clopidogrel. The odds of using ticagrelor over prasugrel increased with older age and history of a cerebrovascular event.
  
  
  CONCLUSIONS
  In 2013, clopidogrel remained the most prescribed agent. Meanwhile, ticagrelor had gradually replaced a substantial portion of prasugrel initiation. Further investigation into outcomes associated with the newer agents, as well as reasons behind the conservative use of the antiplatelet agents, is warranted.
  
  
  BACKGROUND
  No funding was received for the conduct of this study. DiDomenico received an honorarium from Amgen for the preparation of a heart failure drug monograph for Pharmacy Practice News and was a co-investigator on funded research for the Patient-Centered Outcomes Research Institute. DiDomenico also serves as an advisory board member for a heart failure program at Otsuka America Pharmaceuticals and as an advisory board member at Novartis Pharmaceuticals. Touchette has received unrestricted grant funding from Cardinal Health and Sunovion Pharmaceuticals and has also served as a consultant to and director of the American College of Clinical Pharmacy Practice-Based Research Network on a study funded by Pfizer. None of the authors of this study are involved in financial or personal relationships with agencies, institutions, or organizations that inappropriately influenced the statistical analysis plan or interpretation of the results. Study concept and design were contributed by Kim, Lee, Touchette, and Walton, with assistance from DiDomenico and Ardati. Kim and Lee collected the data, and data interpretation was performed by Lee, DiDomenico, and Ardati, along with Kim and Walton and assisted by Touchette. The manuscript was written by Kim and Walton, with assistance from the other authors, and revised by Kim, Walton, and Lee, with assistance from the other authors.
authors.affiliation: 1 Pharmacotherapy Outcomes Research Center, and Department of Pathology, University of Utah, Salt Lake City.
authors.forename: Kibum
authors.initials: K
authors.lastname: Kim
authors.affiliation: 2 Department of Pharmacy Systems, Outcomes and Policy, College of Pharmacy, and Center for Pharmacoepidemiology and Pharmacoeconomic Research, University of Illinois at Chicago.
authors.forename: Todd A
authors.initials: TA
authors.lastname: Lee
authors.affiliation: 2 Department of Pharmacy Systems, Outcomes and Policy, College of Pharmacy, and Center for Pharmacoepidemiology and Pharmacoeconomic Research, University of Illinois at Chicago.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Touchette
authors.affiliation: 3 Center for Pharmacoepidemiology and Pharmacoeconomic Research, and Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: DiDomenico
authors.affiliation: 4 Division of Cardiology, College of Medicine, University of Illinois at Chicago.
authors.forename: Amer K
authors.initials: AK
authors.lastname: Ardati
authors.affiliation: 2 Department of Pharmacy Systems, Outcomes and Policy, College of Pharmacy, and Center for Pharmacoepidemiology and Pharmacoeconomic Research, University of Illinois at Chicago.
authors.forename: Surrey M
authors.initials: SM
authors.lastname: Walton
mesh_terms: D054058:Acute Coronary Syndrome / Q000188:drug therapy*; D000241:Adenosine / Q000031:analogs & derivatives / Q000627:therapeutic use; D000284:Administration, Oral; D000368:Aged; D000077144:Clopidogrel; D004359:Drug Therapy, Combination / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D063868:Patient Outcome Assessment; D062645:Percutaneous Coronary Intervention / Q000379:methods; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D000068799:Prasugrel Hydrochloride / Q000627:therapeutic use; D000077486:Ticagrelor; D013988:Ticlopidine / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D000068799:Prasugrel Hydrochloride; D000077486:Ticagrelor; D000241:Adenosine; D013988:Ticlopidine