Burden of major gastrointestinal bleeding among oral anticoagulant-treated non-valvular atrial fibrillation patients

Real-World Risk of Gastrointestinal Bleeding for Direct Oral Anticoagulants and Warfarin Users: A Distributed Network Analysis Using a Common Data Model

Background/Aims

Early studies on direct oral anticoagulants (DOACs) reported a higher risk of gastrointestinal bleeding (GIB) compared with warfarin; however, recent studies have reported a reduced risk. Therefore, this study was designed to evaluate the risk of GIB in users of DOAC and warfarin.

Methods

Using a common data model, we investigated the comparative risk of GIB in subjects from eight hospitals who were newly prescribed DOACs or warfarin. We excluded subjects who had a prior history of GIB or had been prescribed both medications. After propensity score matching, we analyzed 3,347 matched pairs of new DOAC and new warfarin users.

Results

The risk of GIB in new DOAC users was comparable to that in new warfarin users (hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.65 to 1.40; p=0.808). New DOAC users had a similar risk of GIB to new warfarin users among older patients >65 years (HR, 1.00; 95% CI, 0.69 to 1.52; p=0.997) and in older patients >75 years (HR, 1.21; 95% CI, 0.68 to 2.10; p=0.509). In addition, the risk of GIB was not significantly different between two groups according to sex. We also found that the risk of GIB in DOAC users was 26% lower in edoxaban or apixaban subgroups compared to rivaroxaban or dabigatran subgroups (HR, 0.74; 95% CI, 0.69 to 1.00; p=0.049).

Conclusions

In real-world practice, the risk of GIB in new DOAC users is comparable to that in new warfarin users. In DOAC users, the risk of GIB was lower in edoxaban or apixaban subgroups than rivaroxaban or dabigatran subgroups.

Reproducibility of the AGREE II Tool for Assessing the Methodological Quality of Clinical Practice Guidelines for the Management of Antithrombotic Agents in Patients Undergoing GI Endoscopy

BACKGROUND

Clinical practice guidelines (CPGs) exist for the management of antithrombotic agents in the periendoscopic period; however, their methodological qualities vary. The Appraisal of Guidelines for Research & Evaluation II (AGREE II) tool has been validated for the assessment of the methodological quality of CPGs; however, its reproducibility has not been assessed. The goal of this study was to assess the reproducibility of the AGREE II tool for CPGs published within the last 6 years for the management of antithrombotic agents in the periendoscopic period.

STUDY

A systematic search of PubMed and Embase databases was performed to identify eligible CPGs published between January 1, 2016 and April 14, 2022. The quality of the CPG was independently assessed by 6 reviewers using the AGREE II instrument. The reproducibility was summarized as weighted κ statistic and intraclass correlation coefficient using the SPSS statistical analysis package.

RESULTS

The search yielded 343 citations with 7 CPGs from Europe, Asia, and the United States included in the critical appraisal. The overall mean weighted κ score across all guidelines was 0.300 (range, 0.093 to 0.384) indicating a fair agreement. The overall intraclass correlation coefficient was 0.462 (range, 0.175 to 0.570) for single measures and 0.837 (range, 0.560 to 0.888) for average measures indicating moderate reliability.

CONCLUSIONS

Our study shows only a fair overall interobserver agreement in the methodological quality of the included CPGs. The results suggest the need for education and training of CPG raters to enhance the application of the AGREE II tool to improve its reproducibility.

A systematic critical appraisal of clinical practice guidelines of antithrombotic agents in gastrointestinal endoscopy using the AGREE II tool

BACKGROUND AND AIM

The quality of clinical practice guidelines (CPGs) for the management of antithrombotic agents in patients undergoing gastrointestinal (GI) endoscopy has not been systematically appraised. The goal of this study was to evaluate the methodological quality of CPGs for the management of antithrombotic agents in periendoscopic period published within last 6 years.

METHODS

A systematic search of PubMed and Embase databases was performed to identify eligible CPGs published between January 1, 2016, and April 14, 2022, addressing the management of antithrombotic agents in the periendoscopic period. The quality of the CPG was independently assessed by six reviewers using the Appraisal of Guidelines for Research & Evaluation (AGREE) II instrument. Domain scores were considered of sufficient quality when > 60% and of good quality when > 80%.

RESULTS

The search yielded 343 citations, of which seven CPGs published by the gastroenterology associations in Asia (n = 3), Europe (n = 2), and North America (n = 2) were included for the critical appraisal. The overall median score for the AGREE II domains was 93% (interquartile range [IQR] 11%) for scope and purpose, 79% (IQR 61%) for stakeholder involvement, 79% (IQR 36%) for rigor of development, 100% (IQR 14%) for clarity of presentation, 32% (IQR 36%) for applicability, 93% (IQR 29%) for editorial independence, and 86% (IQR 29%) for overall assessment.

CONCLUSIONS

The findings show that the overall methodological quality of the CPGs for the management of antithrombotic agents in the periendoscopic period varies across the domains. There is significant scope for improvement in the methodological rigor and applicability of CPGs.

Reduction of Upper Gastrointestinal Bleeding Risk With Proton Pump Inhibitor Therapy in Asian Patients With Atrial Fibrillation Receiving Direct Oral Anticoagulant: A Nationwide Population-based Cohort Study

BACKGROUND & AIMS

In patients with atrial fibrillation (AF) receiving direct oral anticoagulant (DOAC), upper gastrointestinal bleeding (UGIB) is a serious complication. There are limited data on the benefit of preventive proton pump inhibitor (PPI) use to reduce the risk of UGIB in DOAC users.

METHODS

We included patients with AF receiving DOAC from 2015 to 2020 based on the Korean Health Insurance Review and Assessment database. The propensity score (PS) weighting method was used to compare patients with PPI use and those without PPI use. The primary outcome was hospitalization for UGIB. Weighted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were evaluated using the Cox proportional hazards regression model.

RESULTS

A total of 165,624 patients were included (mean age: 72.2 ± 10.8 years; mean CHA2DS2-VASc score: 4.3 ± 1.8; mean HAS-BLED score: 3.3 ± 1.2). Among them, 99,868 and 65,756 were in the non-PPI group and PPI group, respectively. During a median follow-up of 1.5 years, the PPI group was associated with lower risks of hospitalization for UGIB and UGIB requiring red blood cell transfusion than non-PPI group (weighted HR, 0.825; 95% CI, 0.761-0.894 and 0.798; 95% CI, 0.717-0.887, respectively, both P < .001). The benefits of PPI on the risk of hospitalization for UGIB were greater in those with older age (≥75 years), higher HAS-BLED score (≥3), prior GIB history, and concomitant use of antiplatelet agent (all P-for-interaction < .1). Low-dose PPI was consistently associated with a lower risk of significant UGIB by 43.6-49.3% (P < .001).

CONCLUSIONS

In this large Asian cohort of patients with AF on DOAC, PPI co-therapy is beneficial for reducing the risk of hospitalization for UGIB, particularly in high-risk patients.

2024 TSOC/TSPS Joint Consensus: Strategies for Advanced Vascular Wound Management in Arterial and Venous Diseases

The Taiwan Society of Cardiology (TSOC) and Taiwan Society of Plastic Surgery (TSPS) have collaborated to develop a joint consensus for the management of patients with advanced vascular wounds. The taskforce comprises experts including preventive cardiologists, interventionists, and cardiovascular and plastic surgeons. The consensus focuses on addressing the challenges in diagnosing, treating, and managing complex wounds; incorporates the perfusion evaluation and the advanced vascular wound care team; and highlights the importance of cross-disciplinary teamwork. The aim of this joint consensus is to manage patients with advanced vascular wounds and encourage the adoption of these guidelines by healthcare professionals to improve patient care and outcomes. The guidelines encompass a range of topics, including the definition of advanced vascular wounds, increased awareness, team structure, epidemiology, clinical presentation, medical treatment, endovascular intervention, vascular surgery, infection control, advanced wound management, and evaluation of treatment results. It also outlines a detailed protocol for assessing patients with lower leg wounds, provides guidance on consultation and referral processes, and offers recommendations for various wound care devices, dressings, and products. The 2024 TSOC/TSPS consensus for the management of patients with advanced vascular wounds serves as a catalyst for international collaboration, promoting knowledge exchange and facilitating advancements in the field of advanced vascular wound management. By providing a comprehensive and evidence-based approach, this consensus aims to contribute to improved patient care and outcomes globally.

Functional outcomes of patients with ischaemic stroke with known atrial fibrillation not on therapeutic anticoagulation

BACKGROUND

Anticoagulation significantly reduces the risk of ischaemic stroke in patients with atrial fibrillation (AF). There are a proportion of patients with known AF who remain off anticoagulation. Aims This study aims to retrospectively compare the baseline characteristics, treatments and functional outcomes between patients with ischaemic stroke and known AF based on their anticoagulation status.

METHODS

A single-centre, retrospective review of consecutive patients with an ischaemic stroke and a known history of AF was conducted.

RESULTS

Two hundred four patients with an ischaemic stroke had documented AF prior to the index admission, of which 126 were anticoagulated. Median admission National Institutes of Health Stroke Scale score was lower for anticoagulated patients, though not statistically significant (5.1 vs 7.0, P = 0.09). Median baseline modified Rankin score (mRS) did not significantly differ. Nonanticoagulated patients were more likely to have large vessel occlusions (37.2% vs 23.8%, P = 0.04) and more likely to receive intravenous thrombolysis (15.4% vs 1.6%, P < 0.01). There was no difference in rates of endovascular clot retrieval between groups (P > 0.05). Unfavourable functional outcome at 90 days (mRS ≥ 3) did not significantly differ between groups (P = 0.51). A total of 38.5% of nonanticoagulated patients had no documented reason for this. Of the patients who survived the index admission, 81.5% of patients who were not anticoagulated on admission received anticoagulation.

CONCLUSIONS

Baseline anticoagulation was associated with milder stroke severity in ischaemic stroke patients with known AF. There was no significant difference in functional outcomes at 90 days between groups. Larger observational studies are required to further assess this cohort.

Definition of factor Xa inhibitor-related, life-threatening gastrointestinal bleeding and guidance on when to use reversal therapy: A Delphi panel

Objective

To define and contextualize life-threatening gastrointestinal (GI) bleeding in the setting of factor Xa (FXa) inhibitor therapy and to derive a consensus-based, clinically oriented approach to the administration of FXa inhibitor reversal therapy.

Methods

We convened an expert panel of clinicians representing specialties in emergency medicine, gastroenterology, vascular medicine, and trauma surgery. Consensus was reached among the clinician panelists using the Delphi technique, which consisted of 2 survey questionnaires followed by virtual, real-time consensus-building exercises.

Results

Hypovolemia and hemodynamic instability were considered the most important clinical signs of FXa inhibitor-related, life-threatening GI bleeds. Clinician panelists agreed that potentially life-threatening GI bleeding should be determined on the basis of hemodynamic instability, signs of shock, individual patient characteristics, and clinical judgment. Last, the panel agreed that all patients with life-threatening, FXa inhibitor-associated GI bleeding should be considered for FXa inhibitor reversal therapy; the decision to reverse FXa inhibition should be individualized, weighing the risks and benefits of reversal; and when reversal is elected, therapy should be administered within 1 h after initial emergency department evaluation, when possible.

Conclusions

Consensus-based definitions of life-threatening GI bleeding and approaches to FXa inhibitor reversal centered on hemodynamic instability, signs of shock, individual patient characteristics, and clinical judgment. The results from this Delphi panel may inform clinical decision-making for the treatment of patients experiencing GI bleeding associated with FXa inhibitor use in the emergency department setting.

Percutaneous Left Atrial Appendage Occlusion: What the Practising Physician Should Know

Non-valvular AF is a common clinical condition associated with an increased risk of thromboembolic complications. As a consequence, oral anticoagulant therapy (OAT) is the cornerstone of non-valvular AF management. Despite the well-established efficacy of OAT, many patients cannot receive this preventive therapy due to bleeding or a high risk of bleeding. The fact that more than 90% of thrombi are formed in the left atrial appendage has led to the development of alternative methods to reduce the embolic risk. Left atrial appendage occlusion (LAAO) is a non-pharmacological option for preventing cardioembolic events in patients with non-valvular AF with a contraindication to OAT. The demand for LAAO procedures is growing exponentially and clinicians should consider this alternative option when managing patients with a contraindication to OAT. This review summarises the current thinking about LAAO.

Proton pump inhibitors and gastroprotection in patients treated with antithrombotic drugs: A cardiologic point of view

Aspirin, other antiplatelet agents, and anticoagulant drugs are used across a wide spectrum of cardiovascular and cerebrovascular diseases. A concomitant proton pump inhibitor (PPI) treatment is often prescribed in these patients, as gastrointestinal complications are relatively frequent. On the other hand, a potential increased risk of cardiovascular events has been suggested in patients treated with PPIs; in particular, it has been discussed whether these drugs may reduce the cardiovascular protection of clopidogrel, due to pharmacodynamic and pharmacokinetic interactions through hepatic metabolism. Previously, the concomitant use of clopidogrel and omeprazole or esomeprazole has been discouraged. In contrast, it remains less known whether PPI use may affect the clinical efficacy of ticagrelor and prasugrel, new P2Y12 receptor antagonists. Current guidelines recommend PPI use in combination with antiplatelet treatment in patients with risk factors for gastrointestinal bleeding, including advanced age, concurrent use of anticoagulants, steroids, or non-steroidal anti-inflammatory drugs, and Helicobacter pylori (H. pylori) infection. In patients taking oral anticoagulant with risk factors for gastrointestinal bleeding, PPIs could be recommended, even if their usefulness deserves further data. H. pylori infection should always be investigated and treated in patients with a history of peptic ulcer disease (with or without complication) treated with antithrombotic drugs. The present review summarizes the current knowledge regarding the widespread combined use of platelet inhibitors, anticoagulants, and PPIs, discussing consequent clinical implications.

Oral anticoagulant switching in patients with atrial fibrillation: a scoping review

INTRODUCTION

Oral anticoagulants (OACs) prevent stroke in patients with atrial fibrillation (AF). Several factors may cause OAC switching.

OBJECTIVES

To examine the phenomenon of OAC switching in patients with AF, including all available evidence; frequency and patterns of switch, clinical outcomes, adherence, patient-reported outcomes, reasons for switch, factors associated with switch and evidence gaps.

DESIGN

Scoping review.

DATA SOURCES

MEDLINE, Embase and Web of Science, up to January 2022.

RESULTS

Of the 116 included studies, 2/3 examined vitamin K antagonist (VKA) to direct-acting OAC (DOAC) switching. Overall, OAC switching was common and the definition of an OAC switch varied across. Switching from VKA to dabigatran was the most prevalent switch type, but VKA to apixaban has increased in recent years. Patients on DOAC switched more to warfarin than to other DOACs. OAC doses involved in the switches were hardly reported and patients were often censored after the first switch. Switching back to a previously taken OAC (frequently warfarin) occurred in 5%-21% of switchers.The risk of ischaemic stroke and gastrointestinal bleeding in VKA to DOAC switchers compared with non-switchers was conflicting, while there was no difference in the risk of other types of bleeding. The risk of ischaemic stroke in switchers from DOAC versus non-switchers was conflicting. Studies evaluating adherence found no significant changes in adherence after switching from VKA to DOAC, however, an increase in satisfaction with therapy were reported. Reasons for OAC switch, and factors associated with OAC switch were mostly risk factors for stroke and bleeding. Clinical outcomes, adherence and patient-reported outcomes were sparse for switches from DOACs.

CONCLUSIONS

OAC switching is common in patients with AF and patients often switch back to an OAC they have previously been on. There are aspects of OAC switching that have received little study, especially in switches from DOACs.

Value of Safety of Anticoagulant Therapy in Elderly Patient with Atrial Fibrillation and High Risk of Bleeding

The review article discusses  the safety issue of anticoagulant therapy in elderly patients with atrial fibrillation and high risk of bleeding.  An evidence base is presented demonstrating the high safety of rivaroxaban in patients over 80  years of age,  with a high risk of bleeding  and cardiovascular complications,  the presence of comorbid  pathology, geriatric syndromes  and chronic kidney disease (including in combination with anemia). The problem of low adherence to treatment in elderly patients and the possibility of solving it were separately considered.

Comparative differences in the risk of major gastrointestinal bleeding among different direct oral anticoagulants: An updated traditional and Bayesian network meta-analysis

Background: The most favorable gastrointestinal (GI) bleeding safety profile among different types of direct oral anticoagulants (DOACs) remains controversial. This meta-analysis includes the latest studies and aims to compare GI bleeding risk associated with the use of various DOACs. Methods: PubMed, Cochrane library, and clinicaltrial.gov were searched. Randomized control trials (RCTs) evaluating the safety of DOACs were identified. The primary endpoint assessed was major GI bleeding. Results: A total of 37 RCTs were included in the analyses. Based on the traditional meta-analysis, the major GI bleeding risk was different among various DOACs (interactive p-value <.10). Network meta-analysis findings showed that no DOACs increased the risk of major GI bleeding compared with conventional therapy. Furthermore, a 10 mg daily administration of apixaban reduced the major GI bleeding risk more than daily doses of 60 mg edoxaban, ≥15 mg rivaroxaban, and 300 mg dabigatran etexilate. No difference was observed between daily doses of 300 mg dabigatran etexilate, 60 mg edoxaban, and ≥15 mg rivaroxaban. The major GI bleeding risk associated with 30 mg daily dose of edoxaban was lower than with 10 mg daily rivaroxaban, and no differences between daily 5 mg apixaban, 30 mg edoxaban, and 220 mg dabigatran etexilate were observed. Conclusion: Differences in the major GI bleeding risk were observed when various DOACs were compared. Among standard-dose DOACs, apixaban was associated with the lowest degree of major GI risk. Among low-dose DOACs, edoxaban was associated with a lower major GI bleeding risk than rivaroxaban.

Risk and Management of Bleeding Complications with Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Venous Thromboembolism: a Narrative Review

Atrial fibrillation (AF) and venous thromboembolism (VTE) are highly prevalent conditions with a significant healthcare burden, and represent the main indications for anticoagulation. Direct oral anticoagulants (DOACs) are the first choice treatment of AF/VTE, and have become the most prescribed class of anticoagulants globally, overtaking vitamin K antagonists (VKAs). Compared to VKAs, DOACs have a similar or better efficacy/safety profile, with reduced risk of intracerebral hemorrhage (ICH), while the risk of major bleeding and other bleeding harms may vary depending on the type of DOAC. We have critically reviewed available evidence from randomized controlled trials and observational studies regarding the risk of bleeding complications of DOACs compared to VKAs in patients with AF and VTE. Special patient populations (e.g., elderly, extreme body weights, chronic kidney disease) have specifically been addressed. Management of bleeding complications and possible resumption of anticoagulation, in particular after ICH and gastrointestinal bleeding, are also discussed. Finally, some suggestions are provided to choose the optimal DOAC to minimize adverse events according to individual patient characteristics and bleeding risk.

All-cause mortality after major gastrointestinal bleeding among patients receiving direct oral anticoagulants: a protocol for a systematic review and meta-analysis

BACKGROUND

Gastrointestinal (GI) bleeding represents the single most frequent site of anticoagulant-related bleeding. Adverse outcomes after major GI bleeding including mortality are not well characterized and, as a result, may be underappreciated in clinical practice. We aim to conduct a systematic review and meta-analysis of the risk for 30-day all-cause mortality after major GI bleeding among patients receiving DOACs.

METHODS

Electronic databases including MEDLINE, EMBASE, and Cochrane CENTRAL will be systematically searched to identify randomized controlled trials and prospective and retrospective cohort studies reporting 30-day all-cause mortality in adults with DOAC-related major GI bleeding. At least two investigators will independently perform study selection, risk of bias assessment, and data extraction. The proportion of deaths following a major GI event relative to the number of major GI bleeding events will be calculated for each individual study, and results across studies will be pooled using random-effects meta-analysis. We will assess risk of bias using criteria proposed by the GRADE group for prognostic studies.

DISCUSSION

The findings of this systematic review and meta-analysis will provide clinicians and patients with estimates of mortality after the most common major bleeding event to support shared decision making about anticoagulation management.

TRIAL REGISTRATION

PROSPERO CRD42022295815.

Payer formulary exclusions of apixaban: how patients respond and potential implications

In recent years, US payers have increased usage of formulary exclusions as a means to help manage costs. Earlier this year, one of the largest pharmacy benefit managers in the country added Eliquis (apixaban), the most widely used anticoagulant, to its list of excluded medicines from its formulary, raising concerns by physicians and patients. In this commentary, we examine the potential impacts of formulary exclusion of a drug like apixaban-a treatment for patients with atrial fibrillation and venous thromboembolism to help prevent stroke and clotting events and which has been demonstrated to have a strong efficacy and safety profile. We discuss the effect of formulary exclusions on patients' ability to access the most clinically appropriate treatment for their health needs, along with possible effects on their health and well-being. We also report descriptive results on apixaban-treated patients with traditional Medicare coverage who faced a formulary exclusion of apixaban in 2017, and these patients' observed behaviors. We found that the majority of these patients remained on apixaban either through pre-emptively switching to a different Part D drug plan with apixaban coverage or applying for formulary exception. Our findings suggest that formulary exclusion did not help to achieve the goal of switching patients to less costly medications but created additional hurdles for patients to access their preferred treatment and increased patient burden. Alternative ways to manage payer costs may be needed to help avoid poor outcomes and reduce the burden placed on patients in their efforts to access life-saving medications.

Protective effect of proton pump inhibitor against gastrointestinal bleeding in patients receiving oral anticoagulants: A systematic review and meta-analysis

AIM

The evidence of a protective effect of proton pump inhibitor (PPI) in oral anticoagulant (OAC) treated patients against gastrointestinal bleeding (GIB) is still lacking. We conducted a meta-analysis to estimate the risk of GIB in patients with OAC and PPI co-therapy.

METHODS

A systematic search of PubMed, EMBASE, Cochrane, and Scopus databases was performed for studies reporting GIB risk in OAC and PPI co-therapy. Primary outcomes were total GIB and major GIB events. Pooled estimates of GIB risk were calculated by a random-effect meta-analysis and reported as odds ratios (OR) and 95% confidence interval (CI).

RESULTS

A total of 10 studies and 1,970,931 patients were included. OAC and PPI co-therapy were associated with a lower odds of total and major GIB; OR (95% CI) was 0.67 (0.62-0.74) for total and 0.68 (0.63-0.75) for major GIB, respectively. No differences in the GIB of PPI co-therapy were observed between Asians and non-Asians (p-for-difference, total GIB=0.70, major GIB=0.75, respectively). For all kinds of OAC except for edoxaban, PPI cotreatment was related to a lower odds of GIB by 24-44%. The protective effect of PPI on total GIB was more significant in concurrent antiplatelets or non-steroidal anti-inflammatory drug users and those with high bleeding risks: patients with previous GIB history, HAS-BLED ≥3, or underlying gastrointestinal diseases.

CONCLUSION

In patients who receive OAC, PPI co-therapy is associated with a lower total and major GIB irrespective of ethnic group and OAC type, except for edoxaban. PPI co-therapy can be considered particularly in high GIB risk patients.

Low-Dose NOACs Versus Standard-Dose NOACs or Warfarin on Efficacy and Safety in Asian Patients with NVAF: A Meta-Analysis

BACKGROUND

The meta-analysis of randomized controlled trials has illustrated that the efficacy of low-dose non-vitamin K antagonist oral anticoagulants is inferior compared with standard-dose non-vitamin K antagonist oral anticoagulants, though they are still frequently prescribed for Asian patients with non-valvular atrial fibrillation. We aimed to further investigate the efficacy and safety of low-dose non-vitamin K antagonist oral anticoagulants by carrying out a meta-analysis of all relevant randomized controlled tri- als and cohort studies.

METHODS

Cochrane Central Register of Controlled Trials, Embase, and MEDLINE were sys- tematically searched from the inception to September 9, 2021, for randomized controlled trials or cohorts that compared the efficacy and/or safety of low-dose non-vitamin K antagonist oral anticoagulants in Asian patients with non-valvular atrial fibrillation. The primary outcomes were stroke and major bleeding, and the secondary outcomes were mortality, intracranial hemorrhage, and gastrointestinal hemorrhage. Hazard ratios and 95% CIs were estimated using the random-effect model.

RESULTS

Nineteen publications involving 371 574 Asian patients with non-valvular atrial fibrillation were included. Compared with standard-dose non-vitamin K antagonist oral anticoagulants, low-dose non-vitamin K antagonist oral anticoagulants showed compa- rable risks of stroke (hazard ratio, 1.18; 95% CI 0.98 to 1.42), major bleeding (hazard ratio, 1.00; 95% CI 0.83 to 1.21), intracranial hemorrhage (hazard ratio, 1.13; 95% CI 0.92 to 1.38), and gastrointestinal hemorrhage (hazard ratio, 1.07; 95% CI 0.87 to 1.31), though had a higher risk of mortality (hazard ratio, 1.34; 95% CI 1.05 to 1.71). Compared with warfarin, low-dose non-vitamin K antagonist oral anticoagulants were associated with lower risks of stroke (hazard ratio, 0.73; 95% CI 0.67 to 0.79), mortality (hazard ratio, 0.69; 95% CI 0.60 to 0.81), major bleeding (hazard ratio, 0.62; 95% CI 0.51 to 0.75), intracranial hemor- rhage (hazard ratio, 0.48; 95% CI 0.33 to 0.69), and gastrointestinal hemorrhage (hazard ratio, 0.78; 95% CI 0.65 to 0.93).

CONCLUSION

Low-dose non-vitamin K antagonist oral anticoagulants were superior to warfarin, and comparable to standard-dose non-vitamin K antagonist oral anticoagu- lants considering risks of stroke, major bleeding, intracranial hemorrhage, and gastroin- testinal hemorrhage. Further, high qualified studies are warranted.

Real-World Comparisons of Low-Dose NOACs versus Standard-Dose NOACs or Warfarin on Efficacy and Safety in Patients with AF: A Meta-Analysis

Objective

We aimed to further investigate the efficacy and safety of low-dose NOACs by performing a meta-analysis of cohort studies.

Background

Meta-analyses of randomized controlled trials (RCTs) have demonstrated that low-dose non-vitamin K antagonist oral anticoagulants (NOACs) showed inferior efficacy compared with standard-dose NOACs, although they are still frequently prescribed for patients with atrial fibrillation (AF) in the clinical practice.

Methods

Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and MEDLINE were systematically searched from the inception to September 9, 2021, for cohort studies that compared the efficacy and/or safety of low-dose NOACs in patients with AF. The primary outcomes were ischemic stroke and major bleeding, and the secondary outcomes were mortality, intracranial hemorrhage (ICH), and gastrointestinal hemorrhage (GH). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with the random-effect model.

Results

Twenty-five publications involving 487856 patients with AF were included. Compared with standard-dose NOACs, low-dose NOACs had comparable risks of ischemic stroke (HR = 1.03, 95% CI 0.96 to 1.11), major bleeding (HR = 1.12, 95% CI 0.97 to 1.28), ICH (HR = 1.09, 95% CI 0.88 to 1.36), and GH (HR = 1.11, 95% CI 0.92 to 1.33), except for a higher risk of mortality (HR = 1.41, 95% CI 1.21 to 1.65). Compared with warfarin, low-dose NOACs were associated with lower risks of ischemic stroke (HR = 0.72, 95% CI .67 to 0.78), mortality (HR = 0.67, 95% CI 0.59 to 0.77), major bleeding (HR = 0.64, 95% CI 0.53 to 0.79), ICH (HR = 0.57, 95% CI 0.42 to 0.77), and GH (HR = 0.78, 95% CI 0.64 to 0.95).

Conclusions

Low-dose NOACs were comparable to standard-dose NOACs considering risks of ischemic stroke, major bleeding, ICH, and GH, and they were superior to warfarin. Low-dose NOACs might be prescribed effectively and safely for patients with AF. Considering limitations, further well-designed prospective studies are foreseen.

Meta-Analysis Comparing Apixaban Versus Rivaroxaban for Management of Patients With Nonvalvular Atrial Fibrillation

To compare the efficacy and safety of apixaban and rivaroxaban for the prevention of stroke in patients with nonvalvular atrial fibrillation (NVAF) by way of a meta-analysis informed by real-world evidence. Systematic review and meta-analysis of observational studies including patients with NVAF on apixaban and rivaroxaban, which reported stroke/systemic embolism and/or major bleeding. Prospero registration number: CRD42021251719. Estimates of relative treatment effect (based on hazard ratios[HRs]) were pooled using the inverse variance method. Fixed-effects and random effect analyses were conducted. Exploratory meta-regression analyses that included study-level covariates were conducted using the metareg (meta-regression) command of Stata Statistical Software: Release 15.1 (College Station, Texas. StataCorp LLC.). Study level covariates explored in the meta-regression analyses were CHA₂DS₂-VASc and HAS-BLED scores. A total of 10 unique retrospective real-world evidence studies reported comparative estimates for apixaban versus rivaroxaban in patients with NVAF and were included in the meta-analysis. Adjusted HR was 0.88 (95% [confidence interval] CI 0.81 to 0.95), indicating a significantly lower hazard of stroke/systemic embolism associated with apixaban versus rivaroxaban. Pairwise meta-analysis for a major bleeding episode was significantly lower with apixaban compared with rivaroxaban (HR 0.62; 95% CI 0.56 to 0.69), whereas apixaban was associated with a lower risk of gastrointestinal bleeding compared with rivaroxaban (HR 0.57; 95% CI 0.50 to 0.64). In conclusion, this study suggests that patient CHA₂DS₂-VASc and HAS-BLED scores might be an important factor when selecting which direct oral anticoagulants to use, given the relation these scores have on treatment outcomes. Apixaban is associated with lower rates of both major and gastrointestinal bleeding than rivaroxaban, with no loss of efficacy.