Prescribing Trends of Oral Anticoagulants in US Patients With Cirrhosis and Nonvalvular Atrial Fibrillation

Recommendations for the safe use of direct oral anticoagulants in patients with cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data

PURPOSE

The popularity of direct oral anticoagulants (DOACs) is increasing among patients with cirrhosis. Cirrhosis has a major impact on the pharmacokinetics of drugs, potentially increasing adverse events. Safe use of drugs in cirrhosis requires a diligent risk-benefit analysis. The aim of this study is to develop practice recommendations for safe use of DOACs in cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data.

METHODS

We conducted a systematic literature search to identify studies on pharmacokinetics, pharmacodynamics and safety of DOACs in cirrhosis. Data were collected and presented in summary tables by severity of cirrhosis using the Child-Turcotte-Pugh (CTP) classification. A multidisciplinary expert panel evaluated the results and classified the DOACs according to safety.

RESULTS

Fifty four studies were included. All DOACs were classified as 'no additional risks known' for CTP A. For CTP B, apixaban, dabigatran and edoxaban were classified as 'no additional risks known'. Apixaban and edoxaban showed fewer adverse events in patients with cirrhosis, while dabigatran may be less impacted by severity of cirrhosis based on its pharmacokinetic profile. Rivaroxaban was classified as 'unsafe' in CTP B and C based on significant pharmacokinetic alterations. Due to lack of data, apixaban, dabigatran and edoxaban were classified as 'unknown' for CTP C.

CONCLUSION

DOACs can be used in patients with CTP A cirrhosis, and apixaban, dabigatran and edoxaban can also be used in CTP B. It is recommended to avoid rivaroxaban in CTP B and C. There is insufficient evidence to support safe use of other DOACs in CTP C cirrhosis.

Efficacy and safety of Apixaban in the treatment of cerebral venous sinus thrombosis: a multi-center study

Background

Information regarding the safety and efficacy of specific direct oral anticoagulants (DOAC) in the treatment of cerebral sinus and venous thrombosis (CSVT) is scarce. Apixaban is one of the most frequently prescribed DOACs. Therefore, we aimed to compare the safety and efficacy of Apixaban with those of vitamin k antagonists (VKA) in patients with CSVT.

Methods

Prospective CSVT databases from seven academic medical centers were retrospectively analyzed. Patients treated with Apixaban were compared to those treated with VKA. Data on demographics, clinical presentations, risk factors, radiological and outcome parameters were studied.

Results

Overall, 403 patients were included in the analysis. Of them, 48 (12%) were treated with Apixaban, and 355 (88%) were treated with VKA. Rates of coagulopathies were significantly higher in the VKA-treated patients but no other differences between the groups were found in baseline characteristics and underlying etiology. No significant differences were found between groups in efficacy or safety parameters including the rates of recanalization, favorable outcomes, one-year mortality, seizures, intracranial hemorrhage or CSVT recurrences.

Conclusion

Our data suggests that Apixaban may be safe and effective for patients with CSVT. These results should be tested in prospective randomized clinical studies.

Engineering and evaluation of FXa bypassing agents that restore hemostasis following Apixaban associated bleeding

Direct oral anticoagulants (DOACs) targeting activated factor Xa (FXa) are used to prevent or treat thromboembolic disorders. DOACs reversibly bind to FXa and inhibit its enzymatic activity. However, DOAC treatment carries the risk of anticoagulant-associated bleeding. Currently, only one specific agent, andexanet alfa, is approved to reverse the anticoagulant effects of FXa-targeting DOACs (FXaDOACs) and control life-threatening bleeding. However, because of its mechanism of action, andexanet alfa requires a cumbersome dosing schedule, and its use is associated with the risk of thrombosis. Here, we present the computational design, engineering, and evaluation of FXa-variants that exhibit anticoagulation reversal activity in the presence of FXaDOACs. Our designs demonstrate low DOAC binding affinity, retain FXa-enzymatic activity and reduce the DOAC-associated bleeding by restoring hemostasis in mice treated with apixaban. Importantly, the FXaDOACs reversal agents we designed, unlike andexanet alfa, do not inhibit TFPI, and consequently, may have a safer thrombogenic profile.

Racial and Ethnic Disparities in Initiation of Direct Oral Anticoagulants Among Medicare Beneficiaries

Importance

The influence of race and ethnicity on initiation of direct oral anticoagulants (DOACs) is relatively understudied in Medicare data.

Objective

To investigate disparities in the initiation of DOACs compared with warfarin by race, ethnicity, and social vulnerability.

Design, Setting, and Participants

This retrospective cohort study used a 50% sample of Medicare fee-for-service data from January 1, 2010, to December 31, 2019 (mean patient enrollment duration, 7.7 years). Analysis took place between January 2023 and February 2024. A cohort of older adults (aged ≥65 years) with atrial fibrillation who newly initiated warfarin or DOACs (dabigatran, rivaroxaban, apixaban, and edoxaban) was identified.

Exposure

Patients were classified as non-Hispanic White, non-Hispanic Black, and Hispanic.

Main Outcomes and Measures

The likelihood of starting use of DOACs compared with warfarin was modeled, adjusting for race, ethnicity, age, sex, county-level social vulnerability, and other clinical factors.

Results

Among 950 698 anticoagulation initiations, consisting of 680 974 DOAC users and 269 724 warfarin users (mean [SD] age, 78.5 [7.6] years; 52.6% female), 5.2% were Black, 4.3% were Hispanic, and 86.7% were White. During the 10-year study period, DOAC use increased for all demographic groups. After adjustment, compared with White patients, Black patients were 23% less likely (adjusted odds ratio [AOR, 0.77; 95% CI, 0.75-0.79) and Hispanic patients were 13% less likely (AOR, 0.87; 95% CI, 0.85-0.89) to initiate DOAC use. Disparities in DOAC initiation were greatest among Black patients in the earlier years but attenuated during the study period. For instance, in 2010, the OR of Black patients initiating DOACs was 0.54 (95% CI, 0.50-0.57), attenuating linearly over time to 0.69 by 2013 (95% CI, 0.65-0.74) and 0.83 (95% CI, 0.78-0.89) by 2017. By 2019, these differences became nonsignificant (OR, 1.08; 95% CI, 0.99-1.18).

Conclusions and Relevance

In this cohort study of Medicare patients with atrial fibrillation, Black and Hispanic patients were less likely to initiate DOACs for atrial fibrillation, although these differences diminished over time. Identifying the factors behind these early disparities is crucial for ensuring equitable access to novel therapies as they emerge for Black and Hispanic populations.

Effectiveness and safety of direct oral anticoagulants among patients with non-valvular atrial fibrillation and liver disease: A multinational cohort study

BACKGROUND AND AIMS

The effects of direct oral anticoagulants (DOACs) in patients with non-valvular atrial fibrillation (NVAF) and liver disease remain poorly understood. Our multinational cohort study assessed the effectiveness and safety of DOACs in this high-risk population.

METHODS

We assembled two population-based cohorts in United Kingdom and in Québec of NVAF patients with liver disease initiating DOACs or vitamin K antagonists (VKAs) between 2011 and 2020. Using an as-treated exposure definition, we compared DOACs to VKAs and apixaban to rivaroxaban. After inverse probability of treatment weighting, Cox proportional hazards models estimated site-specific hazard ratios (HRs) and 95 % confidence intervals (CIs) of ischemic stroke and major bleeding. Site-specific estimates were pooled using random-effects models. Analyses were repeated among NVAF patients with cirrhosis.

RESULTS

There were 11,881 NVAF patients with liver disease (2683 with cirrhosis). Among those, 8815 initiated DOACs (4414 apixaban, 2497 rivaroxaban) and 3696 VKAs. The HRs (95 % CIs) for DOACs compared to VKAs were 1.01 (0.76-1.34) for ischemic stroke and 0.87 (0.77-0.99) for major bleeding. Results were consistent among patients with cirrhosis. The HRs (95 % CIs) for apixaban compared to rivaroxaban were 0.85 (0.60-1.20) for ischemic stroke and 0.80 (0.68-0.95) for major bleeding. This decreased bleeding risk was not observed among patients with cirrhosis (HR, 1.01; 95 % CI 0.72-1.43).

CONCLUSIONS

Among NVAF patients with liver disease, DOACs were as effective and slightly safer than VKAs, and apixaban was as effective but safer than rivaroxaban. The safety benefit with apixaban was not present among patients with cirrhosis.

Practical guide on left atrial appendage closure for the non-implanting physician: an international consensus paper

A significant proportion of patients who suffer from atrial fibrillation (AF) and are in need of thromboembolic protection are not treated with oral anticoagulation or discontinue this treatment shortly after its initiation. This undertreatment has not improved sufficiently despite the availability of direct oral anticoagulants which are associated with less major bleeding than vitamin K antagonists. Multiple reasons account for this, including bleeding events or ischaemic strokes whilst on anticoagulation, a serious risk of bleeding events, poor treatment compliance despite best educational attempts, or aversion to drug therapy. An alternative interventional therapy, which is not associated with long-term bleeding and is as effective as vitamin K anticoagulation, was introduced over 20 years ago. Because of significant improvements in procedural safety over the years, left atrial appendage closure, predominantly achieved using a catheter-based, device implantation approach, is increasingly favoured for the prevention of thromboembolic events in patients who cannot achieve effective anticoagulation. This management strategy is well known to the interventional cardiologist/electrophysiologist but is not more widely appreciated within cardiology or internal medicine. This article introduces the devices and briefly explains the implantation technique. The indications and device follow-up are more comprehensively described. Almost all physicians who care for adult patients will have many with AF. This practical guide, written within guideline/guidance boundaries, is aimed at those non-implanting physicians who may need to refer patients for consideration of this new therapy, which is becoming increasingly popular.

A major research gap: The use of anticoagulants in cirrhosis

Historically, anticoagulants were contraindicated in patients with cirrhosis owing to concerns about bleeding risks. However, recent studies have shown that patients with cirrhosis are not naturally anticoagulated and are at increased risk of prothrombotic events, such as portal venous thrombosis. In this article, we review preclinical and clinical data on the effects of anticoagulants in cirrhosis, including their potential benefits in reducing liver fibrosis, portal hypertension, and improving survival. Despite promising preclinical evidence, clinical translation has proven challenging. Nevertheless, we discuss the use of anticoagulation in specific clinical scenarios, such as patients with atrial fibrillation and portal vein thrombosis, and highlight the need for further research, including randomised-controlled trials, to determine the optimal role of anticoagulants in the management of patients with cirrhosis.

Position Statement on In-hospital/Clinic Point-of-care Coagulation Testing for Anticoagulation Monitoring in Saudi Arabia

Objectives

Hospital overload is a persistent occurrence in daily practice. Interventions such as point-of-care testing (POCT) are needed to alleviate the pressure faced by healthcare providers and administrators.

Methods

An invited panel of experts from Saudi Arabia was formed under the auspices of the Saudi Heart Association in order to discuss local treatment gaps in the management of patients receiving anticoagulation therapy. This was done in a series of meetings, which resulted in the development of official recommendations for the implementation of POCT for anticoagulation monitoring in the country. Recommendations were based on a comprehensive literature review and international guidelines taking into consideration local clinical practice, clinical gaps, and treatment/testing availabilities.

Results

Vitamin K antagonist (VKA)-based anticoagulation therapy requires routine monitoring. POCT is a promising model of care for the monitoring of International Normalized Ratio (INR) in patients receiving oral anticoagulation in terms efficacy, safety and convenience. The availability of POC INR testing should not replace the use of standard laboratory anticoagulation monitoring. However, there are several indications for implementing POCTINR monitoring that was agreed upon by the expert panel. POCT for anticoagulation monitoring should primarily be used in the warfarin (or other VKA) monitoring clinic in order to ensure treatment efficiency, cost-effectiveness of care, patient satisfaction, and quality of life improvement. The expert panel detailed the requirements for the establishment of a warfarin (or other VKA) monitoring clinic in terms of organization, safety, quality control, and other logistic and technical considerations. The limitations of POCT should be recognized and recommendations on best practices should be strictly followed. Core laboratory confirmation should be sought for patients with higher INR results (>4.7) on POCT. Proper training, quality control, and regulatory oversight are also critical for preserving the accuracy and reliability of POCT results.

Conclusions

POCT enables more rapid clinical decision-making in the process of diagnosis (rule-in or rule-out), treatment choice and monitoring, and prognosis, as well as operational decision-making and resource utilization. POCT thus can fulfill an important role in clinical practice, particularly for patients receiving VKAs.