Comparison of short-term clinical outcomes between ticagrelor versus clopidogrel in patients with acute myocardial infarction undergoing successful revascularization; from Korea Acute Myocardial Infarction Registry-National Institute of Health

Abstract

Background: Although ticagrelor has been well-known to improve clinical outcomes in patients with acute myocardial infarction (AMI) without increased bleeding risk, its clinical impacts have not been well established in East Asian patients.

Methods: Between November 2011 and June 2015, a total of 8010 patients (1377 patients were prescribed ticagrelor and 6633 patients clopidogrel) undergoing successful revascularization were analyzed from Korea Acute Myocardial Infarction Registry-National Institute of Health. The patients who discontinued or occurred in-hospital switching between two antiplatelet agents were excluded.

Results: After propensity score matching (1377 pairs), no difference in the composite of cardiac death, MI, stroke, or target vessel revascularization at 6months was observed between two groups (4.2% vs. 4.9%, p=0.499). However, the incidences of in-hospital Thrombolysis In Myocardial Infarction (TIMI) major and minor bleeding were higher in ticagrelor than clopidogrel (2.6% vs. 1.2%, p=0.008; 3.8% vs. 2.5%, p=0.051). The in-hospital mortality was higher in patients with than those without TIMI major bleeding (11.3% vs. 0.9%, p<0.001). In a subgroup analysis, a higher risk for in-hospital TIMI major bleeding with ticagrelor was observed in patients≥75years or with body weight<60kg (odd ratio [OR]=3.209; 95% confidence interval [CI]=1.356-7.592) and in those received trans-femoral intervention (OR=1.996; 95% CI=1.061-3.754).

Conclusions: Our study shows that ticagrelor did not reduce ischemic events yet, however, was associated with increased risk of bleeding complications compared with clopidogrel. Further large-scale, long-term, randomized trials should be required to assess the outcomes of ticagrelor for East Asian patients with AMI.

Keywords: Far East; Hemorrhage; Myocardial infarction; Ticagrelor.