PrevAleNce and Associated factors of inappropriaTe dosing of direct Oral anticoaguLants In pAtients with Atrial Fibrillation: the ANATOLIA-AF Study

PURPOSE

Inappropriate dosing of direct oral anticoagulants is associated with an increased risk of stroke, systemic embolism, major bleeding, cardiovascular hospitalization, and death in patients with atrial fibrillation. The main goal of the study was to determine the prevalence and associated factors of inappropriate dosing of direct oral anticoagulants in real-life settings.

METHODS

This study was a multicenter, cross-sectional, observational study that included 2004 patients with atrial fibrillation. The study population was recruited from 41 cardiology outpatient clinics between January and May 2021. The main criteria for inappropriate direct oral anticoagulant dosing were defined according to the recommendations of the European Heart Rhythm Association.

RESULTS

The median age of the study population was 72 years and 58% were women. Nine-hundred and eighty-seven patients were prescribed rivaroxaban, 658 apixaban, 239 edoxaban, and 120 dabigatran. A total of 498 patients (24.9%) did not receive the appropriate dose of direct oral anticoagulants. In a logistic regression model, advanced age, presence of chronic kidney disease and permanent atrial fibrillation, prescription of reduced doses of direct oral anticoagulants or edoxaban treatment, concomitant use of amiodarone treatment, and non-use of statin treatment were significantly associated with potentially inappropriate dosing of direct oral anticoagulants.

CONCLUSION

The study demonstrated that the prevalence of inappropriate direct oral anticoagulant dosing according to the European Heart Rhythm Association recommendations was 24.9% in patients with atrial fibrillation. Several demographic and clinical factors were associated with the inappropriate prescription of direct oral anticoagulants.

Dual Antithrombotic Therapy with Oral Anticoagulant and P2Y12 inhibitors in Patients with Atrial Fibrillation After Percutaneous Coronary Intervention

BACKGROUND

The efficacy and safety of dual antithrombotic therapy (DAT) with oral anticoagulant and P2Y12 inhibitors (P2Y12i) in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not been well investigated. The purpose of this study was first to evaluate clinical outcomes of DAT with P2Y12i compared with triple antithrombotic therapy (TAT), and then to compare DAT with low-dose prasugrel and DAT with clopidogrel, in patients with AF undergoing PCI.

METHODS

This study was a multicenter, non-interventional, prospective and retrospective registry. A total of 710 patients with AF undergoing PCI between January 2015 and March 2021 at 15 institutions were analyzed. Clinical outcomes within 1 year, including major adverse cardiovascular events (MACE) and major bleeding events (BARC 3 or 5) were compared between patients receiving DAT (n = 239) and TAT (n = 471), and then, compared among prasugrel-DAT (n = 82), clopidogrel-DAT (n = 157), and TAT.

RESULTS

The DAT group showed significantly lower incidence of MACE and major bleeding events compared with the TAT group (log-rank p = 0.013 and 0.047). In the multivariable Cox regression analyses, DAT (p = 0.028), acute coronary syndrome (p = 0.025), and anemia (p = 0.015) were independently associated with MACE. In addition, anemia (p = 0.022) was independently associated with, and DAT (p = 0.056) and thrombocytopenia (p = 0.051) tended to be associated with, major bleeding events. When analyzed among the prasugrel-DAT, clopidogrel-DAT, and TAT groups, there were no significant differences in clinical outcomes between the prasugrel-DAT and clopidogrel-DAT groups, and similar trends were observed for both 2 groups in comparison with the TAT group.

CONCLUSIONS

In AF patients undergoing PCI, DAT was associated with lower incidence of MACE and major bleeding events compared with TAT. In comparison of P2Y12i, there might be no significant difference in the incidence of MACE and bleeding events between prasugrel-based DAT and clopidogrel-based DAT.

Effectiveness and Safety of Reduced and Standard Daily Doses of Direct Oral Anticoagulants in Patients with Nonvalvular Atrial Fibrillation: A Cohort Study Using National Database Representing the Japanese Population

Purpose

To compare the effectiveness and safety of reduced or standard daily doses of direct oral anticoagulants (DOACs) with warfarin in Japanese patients with nonvalvular atrial fibrillation (NVAF). We used post-hoc analyses to identify patient groups that could benefit from reduced-dose DOACs.

Patients and Methods

Using the National Database of Health Insurance Claims and Specific Health Checkups of Japan, we identified 944,776 patients with NVAF who had started an oral anticoagulant after at least one year of non-use between April 2011 and March 2016. We matched patients taking any, reduced, or standard doses of DOACs 1:1 with those taking warfarin. We measured treatment effectiveness based on admission due to stroke or systemic embolism (S/SE) and safety based on admission due to any bleeding (defined as major bleeding, MB). We compared both outcomes between DOACs and warfarin using the Cox proportional hazards model. We used post-hoc analysis to match patients receiving reduced-dose DOACs to those receiving standard-dose DOACs and compared treatment effectiveness and safety.

Results

More than half of patients receiving DOACs used a reduced dose. The occurrences of S/SE and MB in patients receiving any, reduced, or standard doses of DOACs were equal to or lower than those receiving warfarin. In the post-hoc analysis, the risk of S/SE and MB was similar between reduced and standard doses of DOACs except for those with a history of cerebral infarction and CHA2DS2-VASc score ≥3, where the risk of S/SE was lower for reduced doses of any and individual DOACs.

Conclusion

Findings from the current study are consistent with recent Asian and global studies but different from most studies conducted in North America and Europe, where patients receiving a reduced dose of DOACs had an increased risk of S/SE. Future studies should test the reproducibility of results from the current study.

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.

Prescribing Errors With Direct Oral Anticoagulants and Their Impact on the Risk of Bleeding in Patients With Atrial Fibrillation

INTRODUCTION

Anticoagulants are associated with significant harm when used in error, but there are limited data on potential harm of inappropriate treatment with direct oral anticoagulants (DOACs). We conducted a matched case-control study among atrial fibrillation (AF) patients admitting the hospital with a chronic treatment with DOACs, in order to assess factors associated with the risk of major bleeding.

METHODS

Patient data were documented using hospital's computerized provider order entry system. Patients identified with major bleeding were defined as cases and were matched with controls based on the duration of treatment with DOACs and number of chronic medications. Appropriateness of prescribing was assessed based on the relevant clinical guidelines. Conditional logistic regression was used to evaluate the potential impact of safety-relevant prescribing errors with DOACs on major bleeding.

RESULTS

A total number of 509 eligible admissions were detected during the study period, including 64 cases of major bleeding and 445 controls. The prevalence of prescribing errors with DOACs was 33%. Most prevalent prescribing errors with DOACs were "drug dose too low" (16%) and "non-recommended combination of drugs" (11%). Safety-relevant prescribing errors with DOACs were associated with major bleeding [adjusted odds ratio (aOR) 2.17, 95% confidence interval (CI) 1.14-4.12].

CONCLUSION

Prescribers should be aware of the potential negative impact of prescribing errors with DOACs and understand the importance of proper prescribing and regular follow-up.

Interrupted versus uninterrupted anticoagulation therapy for catheter ablation in adults with arrhythmias

BACKGROUND

The management of anticoagulation therapy around the time of catheter ablation (CA) procedure for adults with arrhythmia is critical and yet is variable in clinical practice. The ideal approach for safe and effective perioperative management should balance the risk of bleeding during uninterrupted anticoagulation while minimising the risk of thromboembolic events with interrupted therapy.

OBJECTIVES

To compare the efficacy and harms of interrupted versus uninterrupted anticoagulation therapy for catheter ablation (CA) in adults with arrhythmias.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and SCI-Expanded on the Web of Science for randomised controlled trials on 5 January 2021. We also searched three registers on 29 May 2021 to identify ongoing or unpublished trials. We performed backward and forward searches on reference lists of included trials and other systematic reviews and contacted experts in the field. We applied no restrictions on language or publication status.

SELECTION CRITERIA

We included randomised controlled trials comparing uninterrupted anticoagulation with any modality of interruption with or without heparin bridging for CA in adults aged 18 years or older with arrhythmia.

DATA COLLECTION AND ANALYSIS

Two review authors conducted independent screening, data extraction, and assessment of risk of bias. A third review author resolved disagreements. We extracted data on study population, interruption strategy, ablation procedure, thromboembolic events (stroke or systemic embolism), major and minor bleeding, asymptomatic thromboembolic events, cardiovascular and all-cause mortality, quality of life (QoL), length of hospital stay, cost, and source of funding. We used GRADE to assess the certainty of the evidence.  MAIN RESULTS: We identified 12 studies (4714 participants) that compared uninterrupted periprocedural anticoagulation with interrupted anticoagulation. Studies performed an interruption strategy by either a complete interruption (one study) or by a minimal interruption (11 studies), of which a single-dose skipped strategy was used (nine studies) or two-dose skipped strategy (two studies), with or without heparin bridging. Studies included participants with a mean age of 65 years or greater, with only two studies conducted in relatively younger individuals (mean age less than 60 years). Paroxysmal atrial fibrillation (AF) was the primary type of AF in all studies, and seven studies included other types of AF (persistent and long-standing persistent). Most participants had CHADS2 or CHADS2-VASc demonstrating a low-moderate risk of stroke, with almost all participants having normal or mildly reduced renal function. Ablation source using radiofrequency energy was the most common (seven studies). Ten studies (2835 participants) were conducted in East Asian countries (Japan, China, and South Korea), while the remaining two studies were conducted in the USA. Eight studies were conducted in a single centre. Postablation follow-up was variable among studies at less than 30 days (three studies), 30 days (six studies), and more than 30 days postablation (three studies). Overall, the meta-analysis showed high uncertainty of the effect between the interrupted strategy compared to uninterrupted strategy on the primary outcomes of thromboembolic events (risk ratio (RR) 1.76, 95% confidence interval (CI) 0.33 to 9.46; I2 = 59%; 6 studies, 3468 participants; very low-certainty evidence). However, subgroup analysis showed that uninterrupted vitamin A antagonist (VKA) is associated with a lower risk of thromboembolic events without increasing the risk of bleeding. There is also uncertainty on the outcome of major bleeding events (RR 1.10, 95% CI 0.59 to 2.05; I2 = 6%; 10 studies, 4584 participants; low-certainty evidence). The uncertainty was also evident for the secondary outcomes of minor bleeding (RR 1.01, 95% CI 0.46 to 2.22; I2 = 87%; 9 studies, 3843 participants; very low-certainty evidence), all-cause mortality (RR 0.34, 95% CI 0.01 to 8.21; 442 participants; low-certainty evidence) and asymptomatic thromboembolic events (RR 1.45, 95% CI 0.85 to 2.47; I2 = 56%; 6 studies, 1268 participants; very low-certainty evidence). There was a lower risk of the composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality) in the interrupted compared to uninterrupted arm (RR 0.23, 95% CI 0.07 to 0.81; 1 study, 442 participants; low-certainty evidence). In general, the low event rates, different comparator anticoagulants, and use of different ablation procedures may be the cause of imprecision and heterogeneity observed.

AUTHORS' CONCLUSIONS

This meta-analysis showed that the evidence is uncertain to inform the decision to either interrupt or continue anticoagulation therapy around CA procedure in adults with arrhythmia on outcomes of thromboembolic events, major and minor bleeding, all-cause mortality, asymptomatic thromboembolic events, and a composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality).  Most studies in the review adopted a minimal interruption strategy which has the advantage of reducing the risk of bleeding while maintaining a lower level of anticoagulation to prevent periprocedural thromboembolism, hence low event rates on the primary outcomes of thromboembolism and bleeding. The one study that adopted a complete interruption of VKA showed that uninterrupted VKA reduces the risk of thromboembolism without increasing the risk of bleeding. Hence, future trials with larger samples, tailored to a more generalisable population and using homogeneous periprocedural anticoagulant therapy and ablation source are required to address the safety and efficacy of the optimal management of anticoagulant therapy prior to ablation.