Bleeding risk prediction in elderly patients managed invasively for Acute Coronary Syndromes: external validation of the PRECISE-DAPT and PARIS risk scores

Abstract

Background: Tailoring Dual Antiplatelet Therapy (DAPT) to each patient bleeding and ischemic risk profile is a majopr challenge in everyday clinical practice. As the elderlies were underrepresented in validation cohorts of bleeding risk scores, their generalizability in this context is uncertain. Purpose: We sought to assess the clinical utility of the PRECISE‐DAPT and PARIS bleeding risk scores to elderly patients suffering from ACS and undergoing invasive management. Methods: Our external validation cohort included 1,883 patients older >74 years admitted for ACS and treated with PCI from 3 multicenter, randomized trials. Bleeding risk scores were calculated on a patient‐level and subjects were stratified into risk categories according to each risk score definition. Results: After a median follow‐up of 365 days, patients in the high‐risk categories according to the PRECISE‐DAPT score experienced a higher rate of BARC 3‐5 bleedings (log rank p=0.002) while this was not observed for those in the high‐risk category according to the PARIS risk score (log rank p=0.3). Both scores had a moderate discriminative power (c‐statistics 0.70 and 0.64, respectively) and calibration was accurate for both risk scores (all χ2>0.05), but PARIS risk score was associated to a greater overestimation of the risk (mean D observed‐predicted probability = ‐0.65 for PRECISE DAPT and ‐4.62 for PARIS, p=0.02; Figure 1). Decision curve analysis was in favor of the PRECISE‐DAPT score up to a risk threshold of 2%. A sensitivity showed that calibration and discrimination power was moderate for both risk scores also after including BARC 2 events. Conclusion: In the setting of older adults managed invasively for ACS both the PARIS and the PRECISE‐DAPT scores were moderately accurate in predicting bleeding risk. However, the use of the PRECISE‐DAPT is associated with better performance and a higher net benefit.