Real-world Data and Recommended Dosage of Non-vitamin K Oral Anticoagulants for Korean Patients

Abstract

Regulatory approvals of non-vitamin K antagonist oral anticoagulants (NOACs) have been based on large randomized phase III trials evaluating dabigatran, rivaroxaban, apixaban, or edoxaban relative to warfarin for atrial fibrillation (AF). The results of the trials showed that all NOACs were at least non-inferior to warfarin in the prevention of stroke/thromboembolism and showed lower rates of intracranial bleeding than those associated with warfarin. However, the trials were designed differently, varied in the inclusion/exclusion criteria, and used either one dose or a low/high dose of the NOAC drug. Some of these differences have challenged the ability to directly compare various NOACs, and comparative data on effectiveness and intracranial bleeding are sparse in “real-world” patients. Real-world data complement data from large randomized phase III trials by providing new aspects of the “real-world” absolute risks of ischemic and hemorrhagic stroke associated with NOACs vs. warfarin. Moreover, “real-world” fragile patients might have been included (e.g., patients with increased risk of bleeding, liver disease, and chronic kidney disease), although these patients would be less represented in trials. This paper introduces recently published real-world data of NOACs and further suggests the recommended dosage of NOACs for Korean patients.

Real World Comparison of Rivaroxaban and Warfarin in Korean Patients with Atrial Fibrillation: Propensity Matching Cohort Analysis

“…It only decreased the risk of intracranial hemorrhage event. These were somewhat different results from consequent real-world studies and also different from our study results 815. In those studies, NOACs were better able to reduce major bleeding risk as well as being comparably effective at preventing strokes and thromboembolisms with warfarin.…”

“…There has been worry about relatively higher bleeding risks of rivaroxaban compared with other NOACs 8. Once-daily doses of rivaroxaban would be expected to achieve higher peak and lower trough serum levels than a twice-daily dose.…”

“…However, there has been no study which directly compares the bleeding events between rivaroxaban and the other NOACs. Also, bleeding events in Korean patients with rivaroxaban were consistently lower than warfarin 81620. Before comparison of clinical outcomes between rivaroxaban and the other NOACs, differences of baseline clinical characteristics of enrolled patients should be considered.…”

“…Nonetheless, NOACs had concerns about increased risk of gastrointestinal (GI) bleeding 3456. However, consequent real world data were inconsistent with previous RCTs in terms of GI bleeding which also demonstrated a lower rate in NOACs 78…”

Computed Tomography for Assessment of Left Atrial Appendage Function

“…Third, because of the lack of longitudinal follow-up data, it is unknown whether CT LAA EF can predict future risk in both patients with and without valve surgery. As clinical implication, it would be interesting to know whether the patients with severe valve disease, sinus rhythm and LAA EF <37% would benefit from antithrombotic therapy 6). If yes, which one: anticoagulation versus antiplatelet therapy.…”