Antiplatelet Drug Response Status Does Not Predict Recurrent Ischemic Events in Stable Cardiovascular Patients: Results of the ADRIE Study
Background—The biological response to antiplatelet drugs has repeatedly been shown to predict the recurrence of major adverse cardiovascular events (MACE). However, most studies involved coronary artery disease patients with recent vessel injury, shortly after the initiation of antiplatelet therapy. Data on stable cardiovascular (CV) patients are scarce, and the added predictive value of specific assays (the VASP assay for the clopidogrel response and serum thromboxane B2 for the aspirin response) and aggregation-based assays relative to common predictors has rarely been addressed.
Methods and Results—Stable CV outpatients participating in the ADRIE study (n=771) were tested twice, at two separate visits, with specific and aggregation-based assays. Follow-up lasted 3 years, and fewer than 1% of patients were lost to follow-up. MACE were adjudicated by an independent committee. Multivariate survival analyses included relevant variables identified in univariate analysis and platelet function test results. The C-index was used to express the prognostic value of various multivariate models. MACE, the primary endpoint, occurred in 16% of patients. Hypertension, smoking, older age and elevated LDL cholesterol were predictive of MACE recurrence, with a c-index of 0.63 (P<0.001). Neither the specific nor the aggregation-based assays added significant predictive value for the primary endpoint.
Conclusions—Biological antiplatelet drug responsiveness, measured with specific or aggregation-based assays, has no incremental predictive value over common CV risk factors for MACE recurrence in stable CV outpatients. These results do not support platelet function testing for MACE risk evaluation in stable CV patients.
Clinical Trial Registration Information—clinicaltrials.gov; Identifier: NCT00501423
- Received December 7, 2011.
- Accepted March 28, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited