Comparison of the Efficacy and Safety of Non-vitamin K Antagonist Oral Anticoagulants with Warfarin in Atrial Fibrillation Patients with a History of Bleeding: A Systematic Review and Meta-Analysis

Direct Oral Anticoagulants in Older and Frail Patients with Atrial Fibrillation: A Decade of Experience

INTRODUCTION

Both the prevalence of atrial fibrillation (AF) and its subsequent use of direct oral anticoagulants (DOACs) are rapidly increasing in patients of older age. In the absence of contra-indications, guidelines advocate anticoagulation based on the CHA2DS2-VASc score for all AF patients aged 75 and above. However, some practitioners are hesitant to prescribe anticoagulants to older and frail patients due to perceived elevated bleeding risks. This review delves into the comparative treatment outcomes of DOACs versus vitamin K antagonists (VKAs) in older patients with AF, particularly focusing on those of advanced age, frailty, increased risk of falling, chronic kidney disease (CKD), or with a history of major bleeding. Additionally, considerations on the use of off-label DOAC doses, the role of left atrial appendage (LAA) closure and future developments in factor XIa-inhibitors will be discussed.

RESULTS

While strong evidence supports the use of DOACs in the vital older patients with nonvalvular AF, it remains scant in frail patient groups. There is some evidence from non-randomized studies suggesting that the effect of DOACs compared with VKAs is consistent between frail and nonfrail patients. However, recent findings from a single randomized trial showed increased bleeding risks but comparable thromboembolic outcomes in frail individuals switching from VKAs to DOACs. In patients with an increased risk of falling, data suggest no relevant interaction of increased risk of falling on the effectiveness and safety of DOACs compared with warfarin. Resuming oral anticoagulants in patients with Af after major bleeding seems to be beneficial. Off-label low-dose DOAC is often prescribed to patients who were underrepresented in larger randomized trails because of an elevated risk of bleeding or overexposure to DOACs, but its effect on clinical outcomes remains uncertain.

CONCLUSIONS

DOACs are the recommended oral anticoagulant for vital older patients with AF. The scarcity of data backing DOAC use in frail individuals, those with renal impairments, or significant bleeding history underscores the necessity for further investigation. However, existing evidence suggests at least similar effectiveness and safety and potential benefits for DOACs in these patient subsets. Therefore, there is no reason to suggest these patients should be treated differently than the established guidelines regarding anticoagulation.

Effectiveness and safety of oral anticoagulant therapy in patients with atrial fibrillation with prior gastrointestinal bleeding: A systematic review and meta-analysis

Background

Gastrointestinal bleeding (GIB) commonly complicates anticoagulant therapy for patients with atrial fibrillation (AF). However, AF patients with prior GIB were excluded from most randomized controlled trials on anticoagulation therapy. Therefore, we conducted a systematic review and meta-analysis to assess the effect of oral anticoagulant (OAC) therapy in this specific population.

Methods

Randomized trials and observational studies reporting the data about the resumption of OAC therapy among AF patients with prior GIB were included. The search was performed in the PubMed and Embase databasesup to March 2022. The adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled by a random-effects model with an inverse variance method.

Results

A total of 7 studies involving 57,623 patients were included. Compared with no anticoagulant therapy, OAC therapy was associated with decreased risks of stroke or systemic embolism (HR = 0.71, 95% CI: 0.59–0.84) and all-cause death (HR = 0.66, 95% CI: 0.60–0.72), but there was no significant difference in the risk of recurrent GIB (HR = 1.22, 95% CI: 0.94–1.59). Compared with vitamin K antagonists, non-vitamin K antagonist oral anticoagulants (NOACs) were associated with reduced risks of stroke or systemic embolism (HR = 0.61, 95% CI: 0.54–0.68), all-cause mortality (HR = 0.86, 95% CI: 0.75–0.99), major bleeding (HR = 0.75, 95% CI: 0.66–0.84), and GIB recurrence (HR = 0.83, 95% CI: 0.72–0.96).

Conclusions

In AF patients with prior GIB, OAC therapy (especially NOACs) demonstrated superior effectiveness compared with no anticoagulant therapy.