Arachidonic acid and adenosine diphosphate-induced platelet aggregation rate for predicting mild bleeding in patients with aspirin and clopidogrel

BACKGROUND AND PURPOSE: Mild bleeding, often overlooked but significantly impacting life quality, results from reduced platelet aggregation in antiplatelet-treated patients. Both adenosine diphosphate-induced platelet aggregation rate (PL ADP ) and arachidonic acid-induced platelet aggregation rate (PL AA ) have been shown to predict mild bleeding risk. This study evaluates their predictive value in antiplatelet-treated patients with mild bleeding events. METHODS: This real-world study analyzed the data from antiplatelet-treated patients with mild bleeding events, comparing their PL AA and PL ADP levels to those without bleeding. A multivariate analysis assessed significant variables associated with mild bleeding, including PL AA , PL ADP , and other potential predictors. In the aspirin-bleeding group, patients were stratified based on whether PL AA monitoring was used to adjust therapy during a 6-month follow-up. RESULTS: Among 66 aspirin-treated patients, those with mild bleeding (51.5%) had significantly lower PL AA levels (8.23% vs. 12.05%, P < 0.001). Receiver operating characteristic (ROC) curve analysis identified a PL AA threshold of 8.55% as the best predictor of bleeding risk (area under the curve [AUC] = 0.864, 95% confidence interval [CI]: 0.790–0.939). In dual antiplatelet therapy, patients with mild bleeding (51.79%) had significantly lower PL ADP (29.16% vs. 35.74%, P = 0.009) and PL AA (8.04% vs. 10.85%, P = 0.025) levels. ROC analysis identified PL ADP < 28.96% (AUC = 0.760, 95% CI: 0.635–0.886) and PL AA < 8.01% (AUC = 0.832, 95% CI: 0.713–0.950) as predictive thresholds for bleeding risk. Regular monitoring of PL AA levels (8.55%–20%) was associated with a reduction in bleeding risk for aspirin. In addition, no recurrent strokes were observed, and patients who underwent regular PL AA monitoring experienced lower bleeding rates. CONCLUSION: PL AA and PL ADP are predictive of mild bleeding events induced by antiplatelets. Regular monitoring of platelet aggregation may improve their outcomes. TRIAL REGISTRATION: The clinical trial was registered at Chinese Clinical Trial Registry (ChiCTR2200057621).