Efficacy and safety of ticagrelor versus clopidogrel in patients with non-ST-elevation myocardial infarction in Taiwan

Comparison of Clinical Outcomes Between Ticagrelor and Clopidogrel in East-Asian Patients with Acute Coronary Syndrome: Large Cohort Study

AIM

A high risk of bleeding is observed in East Asian patients with acute coronary syndrome (ACS). Therefore, the choice between two antiplatelet therapy drugs, ticagrelor and clopidogrel, remains controversial in this population with ACS. This study aimed to use a large cohort database to assess the clinical outcomes of ticagrelor and clopidogrel therapy, including major bleeding, recurrent ACS, and mortality, in this population.

METHODS

Between January 2009 and December 2019, 43,696 patients were diagnosed with ACS based on the medical history (International Classification of Diseases [ICD] code) of the Chang Gung Research Database. After excluding patients without percutaneous coronary intervention, with concurrent medical problems, and on non-standard dual antiplatelet therapy (DAPT) or a single antiplatelet agent, 18,046 patients were recruited for analysis. Ticagrelor- and clopidogrel-based DAPT were administered to 3666 patients and 14,380 patients, respectively. Baseline characteristics and clinical outcomes were compared between the two groups. A total of 4225 patients were defined as a high-bleeding-risk subgroup according to Academic Research Consortium for High Bleeding Risk (ARC-HBR) score (met one major or two minor criteria), of which 466 and 3759 patients received ticagrelor- and clopidogrel-based DAPT, respectively.

RESULTS

Before propensity score matching (PSM), younger age, higher prevalence of male sex, and higher body mass index were noted in the ticagrelor-based DAPT group in the whole cohort and high-bleeding-risk subgroup. After PSM, no difference in baseline characteristics and comorbidities between ticagrelor-based and clopidogrel-based DAPT groups in the whole cohort and high-bleeding-risk subgroup was noted. The Kaplan-Meier curves of recurrent ACS and major bleeding were significantly lower in the ticagrelor-based DAPT group than in the clopidogrel-based DAPT group, and that of cardiovascular (CV) and all-cause mortality showed no significant differences. After PSM, in the high-bleeding-risk subgroup, the Kaplan-Meier curve of recurrent ACS was significantly lower in the ticagrelor-based DAPT group than in the clopidogrel-based DAPT group, and that of major bleeding, CV, and all-cause mortality showed no significant differences.

CONCLUSION

In this large cohort study, patients receiving ticagrelor-based DAPT were at lower risk of recurrent ACS compared to those receiving clopidogrel-based DAPT, especially in the patients with myocardial infarction. Ticagrelor-based DAPT did not result in a higher risk of major bleeding in the whole ACS population and high-bleeding-risk subgroup. The rate of CV and all-cause mortality were similar between both the groups.

Comparing the effectiveness and safety of dual antiplatelet with ticagrelor or clopidogrel in elderly Asian patients with acute myocardial infraction

Background

Current guidelines recommend potent P2Y12 inhibitors for patients after acute coronary syndrome. However, the data on the efficacy and safety of potent P2Y12 inhibitors in elderly Asian populations was limited. We aimed to investigate the major adverse cardiovascular events (MACE), bleeding events, and net adverse clinical events (NACE) with ticagrelor and clopidogrel in Taiwanese patients aged 65 and older after acute myocardial infarction (AMI).

Methods

This retrospective population-based cohort study was conducted using data from the National Health Insurance Research Database. The AMI patients aged ≥65 years who underwent percutaneous coronary intervention (PCI) and survived after 1 month were included. The patients were separated into 2 cohorts depending on the type of dual antiplatelet therapy (DAPT) they received: ticagrelor plus aspirin (T + A) or clopidogrel plus aspirin (C + A). We used inverse probability of treatment weighting to balance the difference between these 2 study groups. The outcome included all-cause mortality, MACE (cardiovascular death, nonfatal ischemic stroke, and nonfatal myocardial infarction), intracerebral hemorrhage, major bleeding, and NACE which is composed of cardiovascular death, ischemic and hemorrhagic events. The follow-up period was up to 12 months.

Results

From 2013 to 2017, a total of 14,715 patients who met the eligibility criteria were separated into 2 groups: 5,051 for T + A and 9,664 for C + A. Compared to patients with C + A, patients who received T + A had a lower risk of cardiovascular death and all-cause death, with an adjusted HR of 0.57 [95% confidence interval (CI), 0.38–0.85, p = 0.006] and 0.58 (95% CI 0.45–0.74, p < 0.001), respectively. No differences were found in MACE, intracranial and major bleeding between the 2 groups. In addition, the patients with T + A had a lower risk of NACE with an adjusted HR of 0.86 (95% CI 0.74–1.00, p = 0.045)

Conclusion

Among elderly AMI patients receiving DAPT after successful PCI, ticagrelor was a more favorable P2Y12 inhibitor than clopidogrel because of lowering the risk of death and NACE without increasing the risk of severe bleeding. Ticagrelor is an effective and safe P2Y12 inhibitor in Asian elderly survivors after PCI.

Comparative Safety and Effectiveness of Ticagrelor versus Clopidogrel in Patients With Acute Coronary Syndrome: An On-Treatment Analysis From a Multicenter Registry

Background:

The net clinical benefit of ticagrelor over clopidogrel in acute coronary syndrome (ACS) has recently been questioned by observational studies which did not account for time-dependent confounders. We aimed to assess the comparative safety and effectiveness of ticagrelor vs. clopidogrel accounting for non-adherence in a real-life setting.

Methods

This is a prospective, multicenter cohort study of patients with ACS discharged on ticagrelor or clopidogrel between 2015 and 2019. Major exclusions were previous intracranial bleeding, and the use of prasugrel or oral anticoagulation. Association of P2Y₁₂ inhibitor therapy with 1-year risk of Bleeding Academic Research Consortium Type 3 or 5 bleeding; major adverse cardiac events (MACEs), a composite endpoint of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, or urgent target lesion revascularization; definite/probable stent thrombosis; vascular death; and net adverse clinical event (a composite endpoint of major bleeding and MACE) were analyzed according to the “on-treatment” principle, using fully adjusted Cox and Fine-Gray regression models with doubly robust inverse probability of censoring weighted estimators.

Results

Among 2,070 patients (mean age 63 years, 27% women, 62.5% ST-elevation MI), 1,035 were discharged on ticagrelor and clopidogrel, respectively. Ticagrelor-treated patients were younger and had few comorbidities, but high rates of medication non-compliance, compared with clopidogrel users. After comprehensive multivariate adjustments, ticagrelor did not increase the risk of major bleeding compared with clopidogrel [subhazard ratio, 1.40; 95% confidence interval (CI), 0.96–2.05], while proved superior in reducing MACE (hazard ratio 0.62; 95% CI, 0.43–0.90), vascular death (subhazard ratio, 0.71; 95% CI, 0.52–0.97) and definite/probable stent thrombosis (subhazard ratio, 0.54; 95% CI, 0.30-0.79); thereby resulting in a favorable net clinical benefit (hazard ratio 0.78; 95% CI, 0.60–0.98) compared with clopidogrel. Results from sensitivity analyses were consistent with those from the primary analysis, whereas those from the intention-to-treat (ITT) analysis went in the opposite direction.

Conclusion

Among all-comers with ACS, ticagrelor did not significantly increase the risk of major bleeding, while resulting in a net clinical benefit compared with clopidogrel. Further research is warranted to confirm these findings in high bleeding risk populations.

CREA-ARIAM Andalucía

(ClinicalTrials.gov Identifier: NCT02500290); Current pre-specified analysis (ClinicalTrials.gov Identifier: NCT04630288).