Predictors of P2Y12 Inhibitor Selection in Patients with Acute Coronary Syndrome: The Role of Age and Baseline aPTT Values

Background: Although international guidelines strongly recommend potent P2Y12 inhibitors (ticagrelor) for acute coronary syndrome (ACS) patients, real-world clinical adherence frequently deviates, creating a distinct evidence-practice gap, particularly in developing nations. Aim: This retrospective cross-sectional study aimed to evaluate sociodemographic and laboratory predictors influencing the selection of dual antiplatelet therapy (clopidogrel versus ticagrelor) among 254 ACS patients at a tertiary hospital in Jakarta from January to December 2025. Methode: Data were extracted from medical records and analyzed using multivariate binary logistic regression. Result: The results demonstrated that the vast majority of the cohort (83.8%, n=213) received an aspirin-clopidogrel combination, whereas only 16.1% (n=41) were initiated on ticagrelor. Multivariate analysis identified age and baseline activated partial thromboplastin time (aPTT) as significant independent predictors of therapy selection, specifically revealing that advancing age (aOR 0.946; 95% CI: 0.910–0.983; p=0.005) and prolonged baseline aPTT (aOR 0.854; 95% CI: 0.763–0.992; p=0.039) substantially reduced the probability of ticagrelor prescription. These findings establish that advanced age and prolonged baseline aPTT operate as independent determinants driving clinicians to de-escalate P2Y12 therapy to clopidogrel. Conclusion: This highlights the application of a heuristic approach in real-world clinical practice, where mitigating bleeding risk in vulnerable demographics is systematically prioritized over maximizing the efficacy of potent anti-ischemic agents.