Effect of clopidogrel on post extraction clotting in patients on dual antiplatelet therapy

Abstract

Purpose: To evaluate the association between the platelet inhibition rate of clopidogrel (CLO-PIR) and post-extraction clotting status in DAPT patients.
 Methods: Ninety (90) eligible patients scheduled for a single tooth extraction were enrolled in this study. The CLO-PIR and platelet inhibition rate of aspirin (ASA-PIR) were determined by thromboelastography platelet mapping assay. Post-extraction clotting assessments were performed, and a complete intra-alveolar clot formation within 30 min post-operation was defined as normal clotting. For clot formation exceeding 30 min, it was defined as prolonged bleeding.
 Results: At a similar level of ASA-PIR, a higher proportion of patients with normal CLO-PIR (≤ 75 %) exhibited normal clotting, compared with those featuring high CLO-PIR (>75 %, p < 0.001). However, in patients with similar CLO-PIRs, the clotting results varied insignificantly, with increase in ASA-PIR. The effect of CLO-PIR was further validated using logistic regression analysis (odds ratio = 1.071, 95 % confidence interval: 1.024 - 1.120, p = 0.003), and receiver operating characteristic curve analysis revealed that a 78.6 % CLO-PIR was the rational cut-off point.
 Conclusion: This study preliminarily demonstrates the prominence of high clopidogrel responsiveness in slowing the post-extraction clotting process in DAPT patients.