Early Cessation of Adenosine Diphosphate Receptor Inhibitors Among Acute Myocardial Infarction Patients Treated With Percutaneous Coronary Intervention

Abstract

Background— Guidelines recommend the use of adenosine diphosphate receptor inhibitor (ADPri) therapy for 1 year postacute myocardial infarction; yet, early cessation of therapy occurs frequently in clinical practice. Methods and Results— We examined 11 858 acute myocardial infarction patients treated with percutaneous coronary intervention discharged alive on ADPri therapy from 233 United States TRANSLATE-ACS study (Treatment With Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome) participating hospitals to determine the prevalence of early ADPri cessation (within 1 year), patient-reported reasons for cessation, and associated risk of major adverse cardiovascular events at 1 year. Overall, 2514 (21.2%) of percutaneous coronary intervention–treated patients stopped ADPri by 1 year postmyocardial infarction; the median time from discharge to cessation was 200.5 days (25th, 75th percentiles: 71, 340). Among those with early ADPri cessation, 53.9% received drug-eluting stents and had a median duration of 301 treatment days (25th, 75th percentiles: 137, 353); 33.3% of drug-eluting stent patients stopped treatment within 6 months compared with 64.2% of bare metal stent patients. Those discharged on prasugrel (versus clopidogrel) had a slightly higher likelihood of early ADPri cessation (23.2% versus 21.0%; P =0.03; adjusted hazard ratio, 1.28; 95% confidence interval, 1.17–1.40). Patient-reported reasons for early ADPri cessation included physician-recommended discontinuation (54%), as well as patient self-discontinuation, because of cost (19%), medication side effects (9%), and procedural interruption (10%). Using a time-dependent covariate model, early cessation of ADPri therapy was associated with increased major adverse cardiovascular event (adjusted hazard ratio, 1.40; 95% confidence interval, 1.19–1.65; P <0.0001). Conclusions— One in 5 percutaneous coronary intervention–treated myocardial infarction patients stopped ADPri treatment within 1 year. Early cessation was associated with increased major adverse cardiovascular event risk. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01088503.