Background: Adverse events occur following non-ST elevation acute coronary syndromes (NSTE ACS). However, the timing of these events in relation to index event is less clear.
Methods: Accordingly, we evaluated 26,466 NSTE ACS patients from the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes (GUSTO-IIb), Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT), and Platelet IIb/IIIa Antagonism for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network (PARAGON) A and B trials to ascertain the timing of adverse events. Outcomes of interest were death, myocardial infarction (MI), and death or MI at 180 days. Logistic regression modeling for death was used to categorize patients into low-, medium-, and high-risk groups.
Results: At 6 months, 6.2% of patients died, 12.1% had MI, and 15.7% suffered death or MI. From 15% to 40% of these events occurred beyond 30 days. At 6 months, 3%, 4%, and 13% of patients died in low-, medium-, and high-risk groups, respectively. However, the proportion of patients dying beyond 30 days was similar in the three groups (44%, 43%, and 41% of death, respectively). Similarly, whereas death or MI increased with higher risk (11%, 14%, and 23%, respectively), the proportion of patients with this event beyond 30 days did not differ in the three strata (22%, 20%, and 25%, respectively).
Conclusions: Our study provides important insights into the timing of adverse events and suggests that the substantial proportion of patients suffer subsequent adverse events after their index NSTE ACS. Thus, these data call for continuous surveillance for these events and efforts beyond the acute phase at increasing adherence to evidence-based therapies to improve the outcomes of these patients.