title: Clopidogrel use and early outcomes among older patients receiving a drug-eluting coronary artery stent.
abstract: BACKGROUND
  Clopidogrel use after drug-eluting stent (DES) coronary artery implantation is essential for the prevention of early in-stent thrombosis, but clopidogrel use among older DES recipients has not been widely studied. We sought to identify characteristics associated with failure to fill a clopidogrel prescription and to examine the relationship between a clopidogrel prescription fill and hospitalization for acute myocardial infarction (AMI) or death.
  
  
  RESULTS
  This study was a retrospective analysis of administrative data (20% sample) of 15 996 Medicare Part D enrollees who received a DES in 2006 to 2007. We modeled the adjusted probability and odds of clopidogrel prescription fill within 7 and 90 days of discharge and its association with AMI hospitalization or death. Of the study sample, 19.7% did not fill a clopidogrel prescription within 7 days of discharge, falling to 13.3% by day 90. The adjusted probability of filling a clopidogrel prescription within 7 or 90 days of discharge was lower for patients with dementia (20.2% less likely; 95% CI, 10.4%-30.1%), depression (10.7% less likely; 95% CI, 6.9%-14.5%), age >84 years compared to age 65 to 69 years (10.6% less likely; 95% CI, 8.6%-12.7%), black race (6.6% less likely; 95% CI, 4.2%-9.0%), intermediate levels of medication cost share (5.2% less likely; 95% CI, 2.9%-7.6%), and female sex (3.3% less likely; 95% CI, 2.1%-4.5%). It was higher for patients initially hospitalized for an AMI (12.5% more likely; 95% CI, 11.3%-13.6%). Failure to fill a clopidogrel prescription within 7 days of discharge was associated with a higher adjusted odds ratio of death during days 8 to 90 (2.44; 95% CI, 1.76-3.38) but was not associated with an increased risk of hospitalization for AMI.
  
  
  CONCLUSIONS
  One in 5 patients failed to fill a prescription for clopidogrel at 7 days after DES placement, and 1 in 7 failed to do so by 3 months. Individual characteristics available at the time of hospital discharge were associated with a clopidogrel prescription fill. Those characteristics most strongly associated with nonadherence, including age >84 years, not having an AMI, depression, and dementia, may guide clinicians and health systems seeking to target this high-risk population and improve health outcomes after percutaneous coronary intervention.
authors.affiliation: Division of Cardiology, University of Washington, Seattle, WA 98195-6422, USA. rothg@uw.edu
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Roth
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Morden
authors.forename: Weiping
authors.initials: W
authors.lastname: Zhou
authors.forename: David J
authors.initials: DJ
authors.lastname: Malenka
authors.forename: Jonathan
authors.initials: J
authors.lastname: Skinner
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019917:Blood Vessel Prosthesis Implantation; D000077144:Clopidogrel; D003324:Coronary Artery Disease / Q000150:complications / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy*; D003331:Coronary Vessels / Q000187:drug effects / Q000601:surgery; D003704:Dementia / Q000453:epidemiology*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D054524:Medicare Part D; D055118:Medication Adherence; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D012189:Retrospective Studies; D016019:Survival Analysis; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control; D013988:Ticlopidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D014481:United States
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine