Background: Longitudinal bleeding risk scores have been validated in patients treated with dual antiplatelet therapy (DAPT) following percutaneous coronary intervention. How these scores apply to the population of patients with acute coronary syndrome (ACS) treated without revascularization remains unknown. The objective was to evaluate and compare the performances of the PRECISE-DAPT, PARIS, and DAPT (bleeding component) bleeding risk scores in the medically managed patients with ACS treated with DAPT.
Methods and results: TRILOGY ACS (Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes) was a double-blind, placebo-controlled randomized trial conducted from 2008 to 2012 over a median follow-up of 17.0 months in 966 sites (52 countries). High-risk patients with unstable angina or non-ST-segment-elevation myocardial infarction who did not undergo revascularization were randomized to prasugrel or clopidogrel. The PRECISE-DAPT, PARIS, and DAPT (bleeding component) risk scores were applied in the TRILOGY ACS population to evaluate their performance to predict adjudicated non-coronary artery bypass grafting-related GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) severe/life-threatening/moderate and TIMI (Thrombolysis in Myocardial Infarction) major/minor bleeding with time-dependent c-indices. Among the 9326 participants, median age was 66 years (interquartile range, 59-74 years), and 3650 were females (39.1%). A total of 158 (1.69%) GUSTO severe/life-threatening/moderate and 174 (1.87%) TIMI major/minor non-coronary artery bypass grafting bleeding events occurred. The c-indices (95% CI) of the PRECISE-DAPT, PARIS, and DAPT (bleeding component) scores through 12 months were 0.716 (0.677-0.758), 0.693 (0.658-0.733), and 0.674 (0.637-0.713), respectively, for GUSTO bleeding and 0.624 (0.582-0.666), 0.612 (0.578-0.651), and 0.608 (0.571-0.649), respectively, for TIMI bleeding. There was no significant difference in the c-indices of each score based upon pairwise comparisons.
Conclusions: Among medically managed patients with ACS treated with DAPT, the performances of the PRECISE-DAPT, PARIS, and DAPT (bleeding component) scores were reasonable and similar to their performances in the derivation percutaneous coronary intervention populations. Bleeding risk scores may be used to predict longitudinal bleeding risk in patients with ACS treated with DAPT without revascularization and help support shared decision making. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00699998.
Keywords: acute coronary syndromes; clopidogrel; hemorrhage; myocardial infarction; percutaneous coronary intervention; prasugrel; risk.