'X' marks the spot! Utilising factor Xa inhibitors to optimise thromboprophylaxis in multiple myeloma.

Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality among multiple myeloma patients. Chang and colleagues' findings indicate that factor Xa inhibitors are as effective as warfarin in preventing VTE without raising the risk of gastrointestinal or intracranial bleeding complications. Commentary on: Chang et al. The comparative efficacy and safety of factor Xa inhibitors and warfarin for primary thromboprophylaxis in multiple myeloma patients undergoing immunomodulatory therapy. Br J Haematol 2024 (Online ahead of print). doi: 10.1111/bjh.19612.

Andexanet alpha versus four-factor prothrombin complex concentrate in DOACs anticoagulation reversal: an updated systematic review and meta-analysis.

BACKGROUND: There is currently a lack of evidence for the comparative effectiveness of Andexanet alpha and four-factor prothrombin complex concentrate (4F-PCC) in anticoagulation reversal of direct oral anticoagulants (DOACs). The primary aim of our systematic review was to verify which drug is more effective in reducing short-term all-cause mortality. The secondary aim was to determine which of the two reverting strategies is less affected by thromboembolic events. METHODS: A systematic review and meta-analysis was performed. RESULTS: Twenty-two studies were analysed in the systematic review and quantitative synthesis. In all-cause short-term mortality, Andexanet alpha showed a risk ratio (RR) of 0.71(95% CI 0.37-1.34) in RCTs and PSMs, compared to 4F-PCC (I2 = 81%). Considering the retrospective studies, the pooled RR resulted in 0.84 (95% CI 0.69-1.01) for the common effects model and 0.82 (95% CI 0.63-1.07) for the random effects model (I2 = 34.2%). Regarding the incidence of thromboembolic events, for RCTs and PSMs, the common and the random effects model exhibited a RR of 1.74 (95% CI 1.09-2.77), and 1.71 (95% CI 1.01-2.89), respectively, for Andexanet alpha compared to 4F-PCC (I2 = 0%). Considering the retrospective studies, the pooled RR resulted in 1.21 (95% CI 0.87-1.69) for the common effects model and 1.18 (95% CI 0.86-1.62) for the random effects model (I2 = 0%). CONCLUSION: Considering a large group of both retrospective and controlled studies, Andexanet alpha did not show a statistically significant advantage over 4F-PCC in terms of mortality. In the analysis of the controlled studies alone, Andexanet alpha is associated with an increased risk of thromboembolic events. CLINICAL TRIAL REGISTRATION: PROSPERO: International prospective register of systematic reviews, 2024, CRD42024548768.

Effectiveness and Safety of Direct Oral Anticoagulants Versus Warfarin in Patients with Atrial Fibrillation and Cancer: A Target Trial Emulation from SEER-Medicare Database.

BACKGROUND: Direct oral anticoagulants (DOACs) are preferred over warfarin in patients with atrial fibrillation (AFib). However, their safety and effectiveness in patients with AFib and cancer are inconclusive. METHODS: We conducted a retrospective cohort study by emulating a target trial. Patients with a record of cancer (breast, prostate, or lung), newly diagnosed with AFib initiated DOACs or warfarin within 3 months after AFib diagnosis from the 2012-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare database were included. We compared the risk of ischemic stroke, major bleeding, and secondary outcomes (venous thromboembolism, intracranial bleeding, gastrointestinal bleeding, and non-critical site bleeding) between patients who initiated DOACs and warfarin. Inverse probability treatment weights and inverse probability censoring weights were used to adjust imbalanced patient and disease characteristics and loss to follow-up between the two groups. Weighted pooled logistic regression were used to estimate treatment effect with hazard ratios (HRs) with 95% confidence interval (95% CIs). RESULTS: The incidence rates of stroke and major bleeding between DOAC and warfarin initiators were 9.97 vs. 9.91 and 7.74 vs. 9.24 cases per 1000 person-years, respectively. In adjusted intention-to-treat analysis, patients initiated DOACs had no statistically significant difference in risk of ischemic stroke (HR = 0.87, 95% CI 0.52-1.44) and major bleeding (HR = 1.14, 95% CI 0.77-1.68) compared to those initiated warfarin. In adjusted per-protocol analysis, there was no statistical difference in risk of ischemic stroke (HR = 1.81, 95% CI 0.75-4.36) and lower risk for major bleeding, but the 95% CI was wide (HR = 0.35, 95% CI 0.12-0.99) among DOAC initiators compared to warfarin initiators. The benefits in secondary outcomes were in favor of DOACs. The findings remained consistent across subgroups and sensitivity analyses. CONCLUSION: DOACs are safe and effective alternatives to warfarin in the management of patients with AFib and cancer.

Risk of ischemic stroke associated with direct oral anticoagulants discontinuation on patients with non-valvular atrial fibrillation.

INTRODUCTION: Although direct oral anticoagulants' (DOACs) prescriptions have experienced immense growth in the last decade, the proportion of discontinuers is still common yielding an increased risk of ischemic stroke (IS) onset. AIMS: We aimed to estimate the association between DOACs discontinuation and risk of IS among patients with non-valvular atrial fibrillation (NVAF). METHODS: We used data from a cohort of new DOACs users, followed patients from the first DOAC prescription date up to IS (index date) and conducted a nested case-control analysis using conditional logistic regression. Adjusted odds ratios, 95% confidence intervals were calculated for discontinuation of DOACs (current use compared with past use). The latter, subdivided among those stopping treatment 3 to 2 months and 6 and 3 months prior to index date. The effect of naïve current users against IS onset compared with non-naïve current users was also evaluated. RESULTS: DOACs discontinuation showed an OR of IS of 1.47 (95% CI: 1.02-2.12); estimates were 2.51 (95% CI: 1.84-3.42) for whom discontinued treatment within months 3 and 2 and 1.43 (95% CI: 0.96-2.13) for those between months 6 and 3 prior to index date. Analyzing DOACs individually, risk of IS associated with past users compared with current users: 1.98 (95% CI: 1.25-3.12) for apixaban, 1.38 (95% CI: 0.40-4.72) for edoxaban, 1.98 (95% CI: 1.24-2.65) for dabigatran and 1.87 (95% CI: 1.26-2.76) for rivaroxaban. Similar results were found when stratified by naïve and non-naïve users. CONCLUSIONS: DOACs' discontinuation is associated with higher risk of IS, especially in the second and third months following interruption.

Reversal agents for current and forthcoming direct oral anticoagulants.

Over the past 20 years, there has been a shift from vitamin K antagonists to direct oral anticoagulants (DOACs), which include the thrombin inhibitor dabigatran and the factor Xa inhibitors apixaban, edoxaban, and rivaroxaban. Although DOACs are associated with less serious bleeding than vitamin K antagonists, bleeding still occurs with DOACs, particularly in the elderly and in those with comorbidities. Reversal of the anticoagulant effects of the DOACs may be needed in patients with serious bleeding and in those requiring urgent surgery or intervention. Reversal can be effected with specific agents, such as idarucizumab for dabigatran and andexanet alfa for apixaban, edoxaban, and rivaroxaban, or with non-specific agents, such as prothrombin complex concentrates, activated prothrombin complex concentrate, and recombinant activated factor VII. This paper (i) provides an update on when and how to reverse the DOACs, (ii) describes new reversal agents under development, and (iii) provides a strategic framework for the reversal of the factor XI inhibitors currently under investigation in phase three clinical trials.

Pleiotropic Effects of Direct Oral Anticoagulants in Chronic Heart Failure and Atrial Fibrillation: Machine Learning Analysis.

Oral anticoagulant therapy (OAT) for managing atrial fibrillation (AF) encompasses vitamin K antagonists (VKAs, such as warfarin), which was the mainstay of anticoagulation therapy before 2010, and direct-acting oral anticoagulants (DOACs, namely dabigatran etexilate, rivaroxaban, apixaban, edoxaban), approved for the prevention of AF stroke over the last thirteen years. Due to the lower risk of major bleeding associated with DOACs, anticoagulant switching is a common practice in AF patients. Nevertheless, there are issues related to OAT switching that still need to be fully understood, especially for patients in whom AF and heart failure (HF) coexist. Herein, the effective impact of the therapeutic switching from warfarin to DOACs in HF patients with AF, in terms of cardiac remodeling, clinical status, endothelial function and inflammatory biomarkers, was assessed by a machine learning (ML) analysis of a clinical database, which ultimately shed light on the real positive and pleiotropic effects mediated by DOACs in addition to their anticoagulant activity.

Evidence of potential pro-haemorrhagic drug interactions between CYP3A4 inhibitors and direct oral anticoagulants: Analysis of the FAERS database.

AIMS: There is no consensus on the haemorrhagic risk associated with potential interactions between commonly used CYP3A4 inhibitors and direct oral anticoagulants (DOACs). METHODS: Macrolide antibiotics and azole antimycotics were investigated in this study. Data from Food and Drug Administration Adverse Event Reporting System were retrieved from July 2010 to September 2021. Haemorrhagic signals were expressed by reporting odds ratios (RORs) and 95% confidence intervals (CIs) based on the interaction/noninteraction methodology as (a/c) / (b/d) and considered significant when the lower limit of 95% CI was >1 and the case number of interaction group was ≥3. Subgroup analyses and logistic regression were conducted by adjusting associated factors in haemorrhagic events. RESULTS: From the third quarter of 2010 to the first quarter of 2021, we retrieved 382 853 distinct cases of adverse events associated with DOACs, in which 1128 cases of bleeding were associated with coadministration of CYP3A4 inhibitors and DOACs. The haemorrhagic signal was significant for apixaban when coadministered with clarithromycin (ROR 1.60, 95% CI 1.16-2.20) and posaconazole (ROR 2.69, 95% CI 1.37-5.28). For dabigatran, coadministration with azithromycin (ROR 4.06, 95% CI 2.77-5.95), fluconazole (ROR 2.26, 95% CI 1.52-3.37), itraconazole (ROR 7.52, 95% CI 1.51-37.46) and ketoconazole (ROR 2.06, 95% CI 1.25-3.41) was associated with significantly higher risks of haemorrhages. At the same time, addition of itraconazole to rivaroxaban also indicated significant haemorrhagic signal (ROR 3.58, 95% CI 1.30-9.85). CONCLUSIONS: Macrolide antibiotics and azole antimycotics have potential but different effects on the bleeding risk of DOACs. Close attention is needed when using these drugs together. Such precautions have already been included in some drug labels.

Safety and efficacy of direct oral anticoagulants in stroke prevention in patients with atrial fibrillation complicated with anemia and/or thrombocytopenia: a retrospective cohort study.

BACKGROUND: There are limited data about the clinical benefits and harm of direct oral anticoagulants (DOACs) in stroke prevention in patients with atrial fibrillation (AF) complicated with anemia or thrombocytopenia. METHODS: This is a multi-center retrospective cohort study involving 5469 AF patients from 15 hospitals in China. Patients were divided into three groups according to hemoglobin and platelet levels: Group 1 (hemoglobin male ≥ 130 g/L; female ≥ 120 g/L and platelet ≥ 100 × 109/L), Group 2 (hemoglobin male < 130 g/L; female < 120 g/L or platelet < 100 × 109/L), and Group 3 (hemoglobin male < 130 g/L; female < 120 g/L and platelet < 100 × 109/L). Patients in each category are further divided into two groups according to their stroke prevention strategies: rivaroxaban or dabigatran. Clinical results include major, minor, total bleeding, thrombosis, and the composite outcome of major bleeding and thrombosis. RESULTS: Higher hemoglobin levels were associated with a reduced risk of total bleeding and major bleeding, while platelet counts were not associated with any event. Compared with Group 1, Group 2 had a higher risk of major bleeding (aOR 1.70, 95%CI 1.12-2.57, P = 0.012), and the composite endpoint of major bleeding and thrombosis (aOR 1.70, 95%CI 1.19-2.44, P = 0.004). Compared with Group 1, Group 3 had a higher total bleeding risk (aOR 2.15, 95%CI 1.14-4.05, P = 0.018). Compared with dabigatran, rivaroxaban was associated with higher composite risk in Group 1 (aOR 2.91, 95% CI 1.66-5.16, P < 0.001) and Group 2 (aOR 3.05, 95%CI 1.46-6.39, P = 0.003), but there was no significant difference in Group 3 (aOR 1.78, 95%CI 0.23-13.54, P = 0.577). CONCLUSIONS: Higher hemoglobin levels are associated with a reduced risk of total bleeding and major bleeding in patients with AF. Dabigatran was associated with better clinical outcomes than rivaroxaban in patients with anemia or thrombocytopenia but not in those with anemia and thrombocytopenia.

Direct Oral Anticoagulants: Navigating Through Clinical Challenges.

PURPOSE: Direct oral anticoagulants (DOACs) have been approved, for over a decade, by both European and American medicine agencies, for treatment and prevention of several cardiovascular conditions. Since then, an increasing amount of data has been added to the medical literature day by day, resulting in a dichotomy in selection of the appropriate agent, dosage, and duration of treatment for special populations with multiple comorbidities. Considering these issues, we have prepared a comprehensive review for the clinical practitioner, to optimize the DOAC utilization in clinical practice. METHODS: A thorough literature search and review was conducted, concerning mainly the last decade. Our review focused on the current guidelines and the most recently published studies in PubMed, Science Direct Scopus, and Google Scholar to date. CONCLUSION: The purpose of this study is to provide guidance for healthcare professionals for making proper decisions when confronted with clinical challenges. Nevertheless, further research is required to establish DOAC superiority in complicated cases, where there is clinical uncertainty.

Clinical comprehensive evaluation of direct oral anticoagulants for patients with atrial fibrillation in China.

BACKGROUND: Direct oral anticoagulants (DOACs) are increasingly recommended over warfarin in stroke prevention for patients with non-valvular atrial fibrillation (AF). However, there is an important evidence gap in choosing the most appropriate DOAC for Chinese patients in clinical practice. METHODS: A multi-criteria decision analysis (MCDA) was adopted to build a scoring framework. Attributes and criteria were identified and determined by a scoping literature review, two rounds of Delphi surveys, and a consensus meeting. Weights of each attribute and criterion in the framework were determined using analytic hierarchy process (AHP). Evidence was collected based on the domestic or at least Asian data. Scoring methods for each criterion were developed depended on their characteristics and determined with an expert consensus meeting. Comprehensive scores of each DOAC were calculated based on the utility scores of each criterion and their corresponding weights. RESULTS: A total of 5 attributes, including safety, efficacy, costs/cost-effectiveness, suitability, and accessibility, were determined, and 16 criteria were under the 5 attributes. The safety and efficacy were ranked as the top two important attributes with the weights of 38.8% and 35.9%, respectively, while the suitability received the lowest weight of 7.9%. The comprehensive score for edoxaban was the highest (72.3), followed by dabigatran (49.7), rivaroxaban (37.9), and apixaban (35.8). CONCLUSIONS: This study provided a scoring framework developed for comprehensive evaluation of DOACs in China. The ranking of DOACs could help to support the decision-making in clinical practice. The framework could provide a reference for comprehensive evaluation of other drugs.

Trends in utilization, reimbursement, and price for DOACs and warfarin in the US Medicaid population from 2000 to 2020.

The use of direct oral anticoagulants (DOACs) is widely increasing in the United States (US). Warfarin has been the conventional anticoagulant used in the past few decades, but it has been gradually replaced by DOACs. The objective of the study was to analyze trends in utilization, reimbursement, and price for those anticoagulants in the US Medicaid population. Retrospective data analysis was conducted using the National Summary Files for the Medicaid State Drug Utilization Data. Study drugs included dabigatran, rivaroxaban, apixaban, edoxaban and warfarin. The study assessed secular trends of utilization, reimbursement, and per-prescription price. The data was collected from the first quarter of 2000 through to the second quarter of 2020 restricted for outpatient prescriptions only. During the 21-year study period, a substantial rise in total expenditures on warfarin and DOACs was observed from $144 million in 2000 to $694 million in 2020. Moreover, the utilization of DOACs has increased significantly since the first approval of Xarelto in 2010 from 1079 in 2011 to 1.5 million in 2019. The per-prescription price of DOACs increased from an average of $200 in 2011 to $407 in 2020. Conversely, the total number of prescriptions of Warfarin and branded Coumadin decreased from 2.4 million to 1.4 million and from 3.9 million to less than a million, respectively. The present study demonstrated a change in the trends of US expenditure and utilization for warfarin and DOACs with DOACs representing the majority of market share of both spending per prescription and reimbursement.

Net clinical benefit of DOACs vs. usual anticoagulation treatment in venous thromboembolism and active cancer: systematic review and meta-analysis.

Patients with active cancer are at high risk of recurrent venous thromboembolism (VTE). Usual treatment includes low molecular weight heparin (LMWH), while vitamin K antagonists (VKAs) have also been used as substitutes for LMWH. Direct oral anticoagulants (DOACs) are considered a beneficial alternative to the usual treatment but are accompanied by an increased rate of bleeding compared to LMWH. We conducted a meta-analysis to evaluate the benefits and harms under a common denomination, namely the net clinical benefit (NCB), between DOACs and usual anticoagulation. The primary outcome was NCB-1, defined as non-fatal VTE, major non-fatal bleedings, and all-cause mortality). Co-primary outcomes were 1) NCB-2 (i.e., NCB-1 and clinically relevant non-major bleedings) and 2) NCB-3 (i.e., fatal or non-fatal VTE and major bleedings). A random-effects model was used to calculate outcome risk ratios and 95% confidence intervals (CI). Prospective Register of Systematic Reviews identification number CRD42021284238. We selected 8 studies (n = 4,4461 patients; mean follow-up, 6 months). The NCB-1 and -2 were not different between DOACs and usual anticoagulation, while the NCB-3 showed a reduction of 28% (95% CI, 10-42%), favoring DOACs. Recurrent VTE was reduced by 40% (95% CI, 25-53%) with DOACs than the usual treatment. Different bleeding outcomes and all-cause mortality were not different between treatments. All primary outcomes did not differ between DOACs and LMWH, while NCB-2 and NCB-3 were reduced with DOACs than VKAs. The NCB of DOACs was similar or more favorable to usual anticoagulation in patients with active cancer due to a substantial reduction of VTE and no bleeding excess.

Effectiveness and safety of direct oral anticoagulants versus warfarin in patients with atrial fibrillation and advanced kidney disease.

BACKGROUND: The effectiveness and safety of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) and advanced kidney disease (AKD) has not been fully established. OBJECTIVES: To determine the effectiveness and safety related to pooled or specific DOACs to that with warfarin in patients with AF and AKD. METHODS: Patients with AF and AKD (estimated glomerular filtration rate < 30 mL/min) who received DOAC or warfarin from July 2011 to December 2020 were retrospectively identified in a medical center in Taiwan. Primary outcomes were hospitalized for stroke/systemic embolism and major bleeding. Secondary outcomes included any ischemia and any bleeding. RESULTS: A total of 1,011 patients were recruited, of whom 809 (80.0%) were in the DOACs group (15.3% dabigatran, 25.4% rivaroxaban, 25.2% apixaban, and 14.1% edoxaban), and 202 (20.0%) in the warfarin group. DOACs had considerably lower risks of stroke/systemic embolism (adjusted hazard ratio [aHR] 0.29; 95% CI, 0.09-0.97) and any ischemia (aHR, 0.42; 95% CI, 0.22-0.79), but had comparable risks of major bleeding (aHR, 0.99; 95% CI, 0.34-2.92) and any bleeding (aHR, 0.74; 95% CI, 0.50-1.09) than warfarin. Apixaban was linked to considerably lower risks of any ischemia (aHR, 0.13; 95% CI, 0.04-0.48) and any bleeding (aHR, 0.53; 95% CI, 0.28-0.99) than warfarin. CONCLUSION: Among patients with AF and AKD, DOACs were linked to a lower risk of ischemic events, and apixaban was linked to a lower risk of any ischemia and any bleeding than warfarin.

DOACs and rheumatic valvulopathy: always a red light?

Despite the sharp decline in most high-income industrialized countries, rheumatic heart disease (RHD) continues to be highly prevalent in many rural, low- and middle-income countries. RHD most frequently involves the mitral valve, both in the form of isolated regurgitation and in the form of regurgitation associated with mitral stenosis (mitral stenosis, MS). Atrial fibrillation (AF) is a common complication of RHD that is independently associated with an increased risk of death, heart failure, and systemic thromboembolism. Few studies have focused on the issue of the best oral anticoagulation strategy for patients with RHD and AF. Randomized trials establishing the non-inferiority of new direct oral anticoagulants (DOACs) over vitamin K antagonists (VKAs) in the prevention of stroke and systemic embolism excluded AF patients with mechanical valves or with moderate-to-severe MS. Nevertheless, variable proportions of patients with other VHD types were included. Recently, the INVICTUS trial demonstrated that in patients with RHD-related AF, direct oral anticoagulant rivaroxaban is inferior to VKAs in preventing stroke, systemic embolism, myocardial infarction, or death and is similar in bleeding risk. These results confirm and reinforce the recommendations of current international guidelines supporting the use of VKAs in patients with RHD-related AF.

Telemedicine-Based Management of Oral Anticoagulation Therapy: Systematic Review and Meta-analysis.

BACKGROUND: Oral anticoagulation is the cornerstone treatment of several diseases. Its management is often challenging, and different telemedicine strategies have been implemented to support it. OBJECTIVE: The aim of the study is to systematically review the evidence on the impact of telemedicine-based oral anticoagulation management compared to usual care on thromboembolic and bleeding events. METHODS: Randomized controlled trials were searched in 5 databases from inception to September 2021. Two independent reviewers performed study selection and data extraction. Total thromboembolic events, major bleeding, mortality, and time in therapeutic range were assessed. Results were pooled using random effect models. RESULTS: In total, 25 randomized controlled trials were included (n=25,746 patients) and classified as moderate to high risk of bias by the Cochrane tool. Telemedicine resulted in lower rates of thromboembolic events, though not statistically significant (n=13 studies, relative risk [RR] 0.75, 95% CI 0.53-1.07; I2=42%), comparable rates of major bleeding (n=11 studies, RR 0.94, 95% CI 0.82-1.07; I2=0%) and mortality (n=12 studies, RR 0.96, 95% CI 0.78-1.20; I2=11%), and an improved time in therapeutic range (n=16 studies, mean difference 3.38, 95% CI 1.12-5.65; I2=90%). In the subgroup of the multitasking intervention, telemedicine resulted in an important reduction of thromboembolic events (RR 0.20, 95% CI 0.08-0.48). CONCLUSIONS: Telemedicine-based oral anticoagulation management resulted in similar rates of major bleeding and mortality, a trend for fewer thromboembolic events, and better anticoagulation quality compared to standard care. Given the potential benefits of telemedicine-based care, such as greater access to remote populations or people with ambulatory restrictions, these findings may encourage further implementation of eHealth strategies for anticoagulation management, particularly as part of multifaceted interventions for integrated care of chronic diseases. Meanwhile, researchers should develop higher-quality evidence focusing on hard clinical outcomes, cost-effectiveness, and quality of life. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42020159208; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=159208.

Generic Methods for Simultaneous Analysis of Four Direct Oral Anticoagulants in Human Plasma and Urine by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry.

The new direct oral anticoagulants (DOACs) are increasingly used to treat and prevent thromboembolic disorders, and monitoring concentrations may be valuable in some special scenarios to prevent clinical adverse events. This study aimed to develop generic methods for the rapid and simultaneous analysis of four DOACs in human plasma and urine. Protein precipitation and one-step dilution were used to prepare the plasma and urine; the extracts were injected to ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Chromatographic separation was performed on an Acquity™ UPLC BEH C18 column (2.1 × 50 mm, 1.7 µm) with gradient elution of 7 min. A triple quadrupole tandem mass spectrometer with an electrospray ionization source was employed to analyze DOACs in a positive ion mode. The methods showed great linearity in the plasma (1~500 ng/mL) and urine (10~10,000 ng/mL) for all analytes (R2 ≥ 0.99). The intra- and inter-day precision and accuracy were within acceptance criteria. The matrix effect and extraction recovery were 86.5~97.5% and 93.5~104.7% in the plasma, while 97.0~101.9% and 85.1~99.5% in the urine. The stability of samples during the routine preparation and storage were within the acceptance criteria of less than ±15%. The methods developed were accurate, reliable, and simple for the rapid and simultaneous measurement of four DOACs in human plasma and urine, and successfully applied to patients and subjects with DOACs therapy for anticoagulant activity assessment.

Use of Oral Anticoagulant Drugs in Patients with Pulmonary Hypertension.

Pulmonary hypertension (PH), in particular pulmonary arterial hypertension and chronic thromboembolic PH, burdens patients with relevant morbidity and mortality. The use of oral anticoagulants (OACs) seems able to mitigate the risk of adverse outcomes and death in these patients. Despite scarce evidence, the use of OAC is recommended to treat PH patients, mainly based on observational data. So far, data are still unclear about the impact of direct oral anticoagulant (DOACs), whereas vitamin K antagonists are the main drugs recommended. More data are needed to fully clarify the role of OAC and DOACs in PH patients.

Oral Anticoagulation in Patients with Chronic Liver Disease.

The administration of an anticoagulant in patients with liver disease (nonalcoholic steatohepatitis-NASH, nonalcoholic fatty liver disease-NAFLD, chronic hepatitis, or cirrhosis) who have an indication (atrial fibrillation, venous thrombosis, or pulmonary embolism) is challenging because there is an imbalance between thrombosis and bleeding. There is a need to focus our attention on preventing risk factors because diabetes, obesity, dyslipidemia, smoking, and sedentary behavior are risk factors for both NASH/NAFLD and AF, and these patients require anticoagulant treatment. Patients with advanced liver disease (Child-Pugh C) were excluded from studies, so vitamin K antagonists (VKAs) are still recommended. Currently, VKAs are recommended for other conditions (antiphospholipid syndrome, mitral valve stenosis, and mechanical valve prosthesis). Amongst the patients under chronic anticoagulant treatment, especially for the elderly, bleeding as a result of the improper use of warfarin is one of the important causes of emergency admissions due to adverse reactions. DOACs are considered to be efficient and safe, with apixaban offering superior protection against stroke and a good safety profile as far as major bleeding is concerned compared to warfarin. DOACs are safe in the Child-Pugh A and B classes (except rivaroxaban), and in the Child-Pugh C class are contraindicated. Given that there are certain and reliable data for chronic kidney disease regarding the recommendations, in liver function impairment more randomized studies must be carried out, as the current data are still uncertain. In particular, DOACs have a simple administration, minimal medication interactions, a high safety and effectiveness profile, and now a reversal agent is available (for dabigatran and idarucizumab). Patients are also statistically more compliant and do not require INR monitoring.

Direct Oral Anticoagulants for the Treatment of Venous Thromboembolism in Obesity.

Background: Direct oral anticoagulants (DOACs) are known to have similar efficacy with a decreased risk of bleeding when compared to warfarin for the treatment of venous thromboembolism (VTE). In patients with obesity, there are limited data regarding the safety and efficacy of DOACs. Despite concerns for both under- and over-dosing patients with extremes of body weight, there are no dose adjustment recommendations in the package inserts for any of the DOACs. Objective: To evaluate the safety and efficacy of DOACs versus warfarin for the treatment of VTE in patients with obesity. Methods: This single-center, retrospective cohort study included obese patients initiated on DOAC or warfarin therapy for VTE from January 2015 to January 2022. Patients with cancer, hypercoagulable disorders, end-stage kidney disease, or pregnancy were excluded. The primary endpoint was VTE recurrence. Secondary endpoints included major and minor bleeding. Results: A total of 120 patients met criteria for inclusion. Ninety-two received DOAC therapy and 28 received warfarin. The primary endpoint occurred in 4 patients in the DOAC group and 3 patients in the warfarin group (P = 0.35). Major bleeding occurred in 2 patients. Minor bleeding events occurred in 10 (8.33%) patients. Of those, 6 (6.5%) events occurred in patients receiving a DOAC and 4 (14.3%) events occurred in patients receiving warfarin (P = 0.28). Limitations of this study include the retrospective single-center study design. Conclusions: There was a comparable risk of bleeding and recurrent VTE between DOACs and warfarin in patients initiated on therapy for VTE.

Apixaban Dosing Patterns Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation Receiving Dialysis: A Retrospective Cohort Study.

BACKGROUND & OBJECTIVES: Comparison of clinical outcomes across anticoagulation regimens using different apixaban dosing or warfarin is not well-defined in patients with nonvalvular atrial fibrillation (AF) who are receiving dialysis. This study compared these outcomes in a US national cohort of patients with kidney failure receiving maintenance dialysis. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Patients receiving dialysis represented in the US Renal Data System database 2013-2018 who had AF and were treated with apixaban or warfarin. EXPOSURE: First prescribed treatment with apixaban dosed according to the label, apixaban dosed below the label, or warfarin. OUTCOME: Ischemic stroke/systemic embolism, major bleeding, and all-cause mortality. ANALYTICAL APPROACH: Cox proportional hazards models with inverse probability of treatment weighting. Analyses simulating an intention-to-treat (ITT) approach as well as those incorporating censoring at drug switch or discontinuation (CAS) were also implemented. Inverse probability of censoring weighting was used to account for possible informative censoring. RESULTS: Among 17,156 individuals, there was no difference in risk of stroke/systemic embolism among the label-concordant apixaban, below-label apixaban, and warfarin treatment groups. Both label-concordant (HR, 0.67 [95% CI, 0.55-0.81]) and below-label (HR, 0.68 [95% CI, 0.55-0.84]) apixaban dosing were associated with a lower risk of major bleeding compared with warfarin in ITT analyses. Compared with label-concordant apixaban, below-label apixaban was not associated with a lower bleeding risk (HR, 1.02 [95% CI, 0.78-1.34]). In the ITT analysis of mortality, label-concordant apixaban dosing was associated with a lower risk versus warfarin (HR, 0.85 [95% CI, 0.78-0.92]) while there was no significant difference in mortality between below-label dosing of apixaban and warfarin (HR, 0.97 [95% CI, 0.89-1.05]). Overall, results were similar for the CAS analyses. LIMITATIONS: Study limited to US Medicare beneficiaries; reliance on administrative claims to ascertain outcomes of AF, stroke, and bleeding; likely residual confounding. CONCLUSIONS: Among patients with nonvalvular AF undergoing dialysis, warfarin is associated with an increased risk of bleeding compared with apixaban. The risk of bleeding with below-label apixaban was not detectably less than with label-concordant dosing. Label-concordant apixaban dosing is associated with a mortality benefit compared to warfarin. Label-concordant dosing, rather than reduced-label dosing, may offer the most favorable benefit-risk trade-off for dialysis patients with nonvalvular AF.