Dual non-responsiveness to antiplatelet treatment is a stronger predictor of cardiac adverse events than isolated non-responsiveness to clopidogrel or aspirin.
BACKGROUND
High platelet reactivity (HPR) under treatment with clopidogrel or aspirin is associated with adverse outcome. We aimed to investigate whether high platelet reactivity (HPR) to both aspirin and clopidogrel is a stronger predictor of adverse events compared to isolated HPR to clopidogrel or aspirin.


METHODS
In this prospective cohort study platelet reactivity to adenosine diphosphate (ADP) and arachidonic acid (AA) was assessed by Multiple Electrode Aggregometry (MEA) in 403 patients undergoing percutaneous coronary intervention. The rates of the composite of cardiac adverse events (acute coronary syndrome, stent thrombosis, stroke, death and revascularization) were recorded during 12-month follow-up.


RESULTS
The composite endpoint of cardiovascular adverse events occurred more often in patients with high platelet reactivity (HPR) to both agonists ADP and AA (37.5%) than in those with isolated HPR to ADP (33.3%), AA (25.6%) or without any HPR (18.6%; p=0.003). Classification tree analysis indicated that any HPR emerged as an independent predictor influencing outcome, which was associated with a 1.75 higher risk of cardiac adverse events (OR=1.75: 95%CI=1.1-2.9). Interestingly, the predictive value of HPR tended to be greater among patients with diabetes mellitus (OR=2.18; 95%CI=1.20-3.95). C-reactive protein and diabetes mellitus were independent predictors of high platelet reactivity to both agonists.


CONCLUSIONS
Dual low responsiveness to clopidogrel and aspirin is a strong predictor of cardiac adverse events, especially in patients with diabetes mellitus, which underlines the need for personalized antiplatelet treatment.
Department of Cardiology, Medical University of Vienna, Austria. jolanta.siller-matula@meduniwien.ac.at
Jolanta M
JM
Siller-Matula
Georg
G
Delle-Karth
Günter
G
Christ
Thomas
T
Neunteufl
Gerald
G
Maurer
Kurt
K
Huber
Alexander
A
Tolios
Christa
C
Drucker
Bernd
B
Jilma
D000368:Aged; D001241:Aspirin / Q000008:administration & dosage*; D002318:Cardiovascular Diseases / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D000077144:Clopidogrel; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects / Q000502:physiology*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D016896:Treatment Outcome
D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin