Non-vitamin K antagonist oral anticoagulants for stroke prevention in atrial fibrillation: safety issues in the elderly

Efficacy and Safety of Antithrombotic Therapy With Oral Anticoagulants in Real-World Elderly Patients With Acute Coronary Syndrome and Atrial Fibrillation

Background

The efficacy and safety of antithrombotic treatment with oral anticoagulants (OACs) in elderly patients with comorbidities of acute coronary syndrome (ACS) and atrial fibrillation (AF) are unclear.

Methods

A cohort of hospitalized elderly patients (≥65 years of age) diagnosed with ACS and AF and treated with oral antithrombotic agents were consecutively recruited. Follow-up was performed for at least 1 year. Major adverse cardiac events (MACEs) were defined as a composite of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and systemic embolism. The safety outcomes of bleeding were defined according to the Bleeding Academic Research Consortium (BARC) criteria.

Results

A cohort of 548 eligible patients (76 ± 6.6 years) was analyzed. Compared to the patients with OAC treatment (n = 184, 33.6%), patients treated without OAC (n = 364, 66.4%) were older, had a lower prevalence of persistent AF and unstable angina (UA), and more often presented with paroxysmal AF, acute myocardial infarction (AMI), stent implantation and dual antiplatelet therapy (DAPT). Compared to the patients without OAC treatment (n = 364, 66.4%), patients treated with OAC (n = 184, 33.6%) had a lower risk of MACEs at both the 1-year (4.3 vs. 15.1%, adjusted HR: 0.34, 95% CI: 0.15–0.80, p = 0.014) and 5-year (17.5 vs. 48.4%, adjusted HR: 0.36, 95% CI: 0.19–0.67, p = 0.001) follow-up. No significant difference was observed for bleeding events of BARC ≥2 between the groups (8.0 vs. 9.0%, adjusted HR: 1.17, 95% CI: 0.58–2.34, p = 0.667). Compared with warfarin-treated patients, the non-vitamin K antagonist oral anticoagulant-treated patients had lower risks of all-cause mortality (2.1 vs. 9.5%, HR: 0.18, 95% CI: 0.03–0.98, p = 0.047) and bleeding events of BARC ≥ 3 (2.1 vs. 4.8%, HR: 0.14, 95% CI: 0.02–1.10, p = 0.062).

Conclusions

Antithrombotic therapy with OACs in elderly patients with ACS and AF was associated with a lower risk of ischemic events without an increase in bleeding events. In real-world practice, the clinical awareness of anticoagulation treatments in elderly patients with ACS and AF needs to be strengthened.

Major Bleeding Risk in Atrial Fibrillation Patients Co-Medicated With Non-Vitamin K Oral Anticoagulants and Antipsychotics

Major bleeding risks associated with non-vitamin K oral anticoagulants (NOACs) used with and without concurrent antipsychotics in patients with non-valvular atrial fibrillation (AF) were assessed. A total of 98,863 patients with non-valvular AF receiving at least one NOAC prescription from Taiwan’s National Health Insurance database were enrolled. Major bleeding was defined as a primary diagnosis of intracranial or gastrointestinal hemorrhage or bleeding at other sites. The adjusted incidence rate difference (AIRD) per 1,000 person-years and adjusted rate ratio of major bleeding were estimated using Poisson regression and inverse probability of treatment weighting using the propensity score. A total of 8,037 major bleeding events occurred during 705,521 person-quarters with NOAC prescriptions. Antipsychotics were used in 26.35% of NOAC-exposed patients. Compared to using NOAC alone, co-medication of either typical (AIRD: 79.18, 95% confidence interval [CI]: 70.63–87.72) or atypical (AIRD: 40.5, 95% CI: 33.64–47.35) antipsychotic with NOAC had a significant increase in the adjusted incidence rate per 1,000 person-years of major bleeding. The concomitant use of a NOAC with chlorpromazine (AIRD: 103.87, 95% CI: 51.22–156.52), haloperidol (AIRD: 149.52, 95% CI: 125.03–174.00), prochlorperazine (AIRD: 90.43, 95% CI: 78.55–102.32), quetiapine (AIRD: 44.6, 95% CI: 37.11–52.09), or risperidone (AIRD: 41.55, 95% CI: 22.86–60.24) (All p < 0.01) showed a higher adjusted incidence rate of major bleeding than using NOACs alone. The concomitant use of typical (chlorpromazine, haloperidol, or prochlorperazine) or atypical (quetiapine or risperidone) antipsychotic with NOACs was associated with a significantly increased risk of major bleeding.

Non-Vitamin K Oral Anticoagulant After Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis

Objective: We aimed to compare non-vitamin K oral anticoagulants (NOACs) with a traditional antithrombotic such as vitamin K antagonist (VKA) and antiplatelet agents in patients after transcatheter aortic valve replacement (TAVR).

Methods: We conducted a search in PubMed, EMBASE, and the Cochrane Library until November 2021 for studies involving comparisons of any type of NOACs, including dabigatran, apixaban, rivaroxaban, and edoxaban, with VKA or antiplatelet agents after TAVR. A comparison of NOACs versus VKA was performed in patients with an indication for oral anticoagulation. In addition, we compared NOACs versus antiplatelet in patients without such indication. We calculated the hazard ratios with 95% confidence intervals (CIs) to determine long-term outcomes. The primary outcome was a combined endpoint consisting of all-cause mortality, stroke, major bleeding, or any related clinical adverse events. Secondary outcomes were all-cause mortality, major bleeding, and stroke, respectively.

Results: A total of 10 studies including 10,563 patients after TAVR were included in this meta-analysis. There were no significant differences in any of the long-term outcomes between the NOAC and VKA groups. Although there were no significant differences in the combined endpoint, major bleeding, or stroke, a significant difference was observed in the all-cause mortality (HR 1.74, 95% CI 1.25–2.43, p = 0.001) between the NOAC and antiplatelet groups.

Conclusion: For patients with an indication for oral anticoagulation after TAVR, NOACs seem to be associated with noninferior outcomes compared with VKA therapy. However, for patients without an indication for oral anticoagulation, NOACs appear to be associated with a higher risk of all-cause death as compared with antiplatelet treatment.

Systematic Review Registration:https://clinicaltrials.gov/, identifier CRD42020155122.