How to choose appropriate direct oral anticoagulant for patient with nonvalvular atrial fibrillation

Use of DOACs in frail elderly patients in light of class genericization

BACKGROUND

Frailty and comorbidity influence the therapeutic approach in everyday clinical practice. The DOACs genericization opens a reflection on their differences from a pharmacological and bioavailability point of view, particularly in elderly frail patients. The aim of this project was to create a national Delphi consensus on the topic of the use of DOACs for atrial fibrillation (AF) in such patients, in light of the genericization of the class.

METHODS AND RESULTS

The consensus dealt with 3 main topics: a) efficacy and safety of DOACs in elderly and/or frail patients; b) therapeutic choice in specific frailty scenarios; c) DOACs genericization. 56 cardiologists, two internists and two neurologists from Italy expressed their level of agreement on each statement by using a 5-point Likert scale (1: strongly disagree, 2: disagree, 3: uncertain, 4: agree, 5: strongly agree). A positive consensus was reached if the percentage of agreement (vote 1-2, positive consensus) or disagreement (votes 4-5, negative consensus) was >66%; otherwise, no consensus was reached. Results are displayed accordingly.

CONCLUSIONS

After 10 years of everyday clinical management of DOACs for AF, specific elements differentiating a molecule from another, either for efficacy or for safety, are consolidated. However, some uncertainties still exist in particular contexts, such as chronic kidney disease or cancer patients. Clinicians have an unsure attitude towards generic drugs, because clinical practice is lacking as well as a proper knowledge of the topic. Albeit being an alternative, the choice of the generic drug must remain the responsibility of the clinician.

Comparison between non-vitamin K oral antagonist versus warfarin in atrial fibrillation with and without valvular heart disease: a systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) poses a significant stroke risk in heart disease patients. This systematic review aims to evaluate the efficacy and safety of non-vitamin K oral antagonists (NOACs) versus vitamin K antagonists (VKAs) in AF patients with and without any valvular heart disease (VHD/N-VHD).

METHODS

A systematic search was conducted on PubMed, Scopus, and Google Scholar up to March 3, 2022. Efficacy and safety parameters were analyzed.

RESULTS

A total of 85,423 subjects from 10 studies were included in this meta-analysis. NOACs and VKAs showed similar effects on ischemic stroke in AF patients with VHD/N-VHD (RR 0.97; 95% CI 0.72-1.30; p = 0.83) and also on systemic embolic events (RR 1.02; 95% CI 0.83-1.25; p = 0.86). Similar effects were seen in VHD and N-VHD subgroups. Both treatments had similar effects on myocardial infarction in AF patients with VHD/N-VHD (RR 0.79; 95% CI 0.49-1.26; p = 0.32), VHD (RR 0.78; 95% CI 0.59-1.02; p = 0.07), and N-VHD subgroups (RR 0.82; 95% CI 0.30-2.21; p = 0.69). NOACs reduced the risk of intracranial bleeding in AF VHD/N-VHD (RR 0.64; 95% CI 0.54-0.77; p < 0.0001), VHD (RR 0.59; 95% CI 0.42-0.82; p = 0.002), and N-VHD subgroups (RR 0.70; 95% CI 0.57-0.85; p = 0.0003). Additionally, NOACs reduced the risk of gastrointestinal bleeding in AF VHD/N-VHD (RR 0.80; 95% CI 0.66-0.96; p = 0.02), specifically in the VHD subgroup (RR 0.69; 95% CI 0.54-0.89; p = 0.004). Moreover, NOACs were associated with a decreased risk for minor and non-fatal bleeding in AF patients with VHD/N-VHD (RR 0.86; 95% CI 0.75-0.99; p = 0.04).

CONCLUSION

NOACs are effective and safe for ischemic stroke, systemic embolic events, myocardial infarction, intracranial bleeding, and gastrointestinal bleeding in AF patients with VHD/N-VHD.

Chronic Lymphocytic Leukemia: Management of Adverse Events in the Era of Targeted Agents

The treatment landscape for CLL has undergone a profound transformation with the advent of targeted agents (TAs) like Bruton's Tyrosine Kinase inhibitors (BTKis) and BCL-2 inhibitors (BCL-2is). These agents target crucial cellular pathways in CLL, offering superior efficacy over traditional chemo-immunotherapy, which has led to improved progression-free and overall survival rates. This advancement promises enhanced disease control and potentially normal life expectancy for many patients. However, the journey is not without challenges, as these TAs are associated with a range of adverse events (AEs) that can impact treatment efficacy and patient quality of life. This review focuses on detailing the various AEs related to TA management in CLL, evaluating their frequency and clinical impact. The aim is to present a comprehensive guide to the effective management of these AEs, ensuring optimal tolerability and efficacy of TAs. By reviewing the existing literature and consolidating findings, we provide insights into AE management, which is crucial for maximizing patient outcomes in CLL therapy.

Outcomes of direct oral anticoagulants with aspirin vs warfarin with aspirin: a registry-based cohort study

Background

For patients anticoagulated with direct oral anticoagulants (DOACs) or warfarin and on aspirin (ASA) for nonvalvular atrial fibrillation and/or venous thromboembolism, it is unclear if bleeding outcomes differ.

Objectives

To assess bleeding rates for ASA with DOACs vs warfarin and one another.

Methods

Registry-based cohort study of patients followed by a 6-center quality improvement collaborative in Michigan using data from 2009 to 2022. The study included adults on ASA with warfarin or DOACs for atrial fibrillation and/or venous thromboembolism without a recent myocardial infarction or heart valve replacement.

Results

After propensity matching by anticoagulant class, we compared 2 groups of 1467 patients followed for a median of 18.0 months. Any bleeding and nonmajor bleeding was increased with DOACs + ASA compared with warfarin + ASA (32.2 vs 27.8 and 27.1 vs 22.9 events/100 patient-years; relative risks [RRs], 1.1 and 1.2; 95% CIs, 1.1-1.2 and 1.1-1.3, respectively). After matching by drug, patients on apixaban + ASA vs warfarin + ASA had more bleeding (31.2 vs 27.8 events/100 patient-years; RR, 1.1; 95% CI, 1.0-1.2) and nonmajor bleeding but less major bleeding (3.8 vs 4.7 events/100 patient-years; RR, 0.8; 95% CI, 0.6-1.0) and emergency room visits for bleeding. Patients on rivaroxaban + ASA vs warfarin + ASA had more bleeding (39.3 vs 26.3 events/100 patient-years, RR, 1.5; 95% CI, 1.3-1.6), nonmajor bleeding, and thrombosis. Patients on apixaban + ASA vs rivaroxaban + ASA had significantly less bleeding (22.5 vs 39.3/100 patient-years; RR, 0.6; 95% CI, 0.5-0.7), nonmajor bleeding, major bleeding (2.1 vs 5.5 events/100 patient-years; RR, 0.4; 95% CI, 0.2-0.6), emergency room visits for bleeding, and thrombotic events.

Conclusion

Patients on DOAC + ASA without a recent myocardial infarction or heart valve replacement had more nonmajor bleeding but otherwise similar outcomes compared with warfarin + ASA. Patients treated with rivaroxaban + ASA experienced more adverse clinical events compared with warfarin + ASA or apixaban + ASA.

Comparison of the efficacy and safety between rivaroxaban and dabigatran in the treatment of acute portal vein thrombosis in cirrhosis

BACKGROUND

New oral anticoagulants (NOACs) have been becoming prevalent in recent years and are increasingly used in the treatment of port vein thrombosis. The difference of the efficacy and safety between rivaroxaban and dabigatran remains unclear in the treatment of cirrhotic patients with acute portal vein thrombosis (PVT).

METHODS

This retrospective study included all consecutive cirrhotic patients with acute portal vein thrombosis in our institute from January 2020 to December 2021. The patients received oral anticoagulation with rivaroxaban or dabigatran. The demographic, clinical, and imaging data of patients were collected. The diagnosis of acute PVT was confirmed by imaging examinations. The severity of liver cirrhosis was assessed using Child-Pugh score and Model for End-Stage Liver Disease (MELD) score. Outcomes included recanalization (complete, partial, and persistent occlusion), liver function, bleedings, and survival. The log-rank test was used to compare Kaplan-Meier distributions of time-to-event outcomes. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

A total of 94 patients were included, 52 patients (55%) received rivaroxaban and 42 (45%) with dabigatran. The complete and partial recanalization of PVT was observed in 41 patients. There was no significant difference in complete recanalization, partial recanalization, and persistent occlusion between the two groups. With multivariate analysis, D-dimer (HR 1.165, 95% CI 1.036-1.311, p = 0.011) was independent predictors of complete recanalization. The Child-Pugh score (p = 0.001) was significantly improved in both two groups after anticoagulation, respectively. However, there was no difference between the two groups. The probability of survival was 94%, 95% in the rivaroxaban and dabigatran groups (log-rank p = 0.830). Major bleedings were reported in 3 patients (6%) in rivaroxaban group and 1 patient (2%) in dabigatran group (p = 0.646). Six patients (12%) in rivaroxaban group experienced minor bleeding, and five (12%) from dabigatran group (p = 0.691).

CONCLUSIONS

The efficacy and safety were comparable between rivaroxaban and dabigatran in the treatment of cirrhotic patients with acute portal vein thrombosis. And D-dimer can contribute to the prediction of PVT recanalization in cirrhotic patients.

Bleeding Disorders and Dental Implants: Review and Clinical Indications

BACKGROUND

Bleeding disorders can be divided into three categories: congenital coagulation disorders (CCDs), antiplatelet-induced bleeding disorders (APBDs) and anticoagulant-induced bleeding disorders (ACBDs). Implant placement can be challenging in these kinds of patients. The aim of this study is to provide evidence on implant surgery in patients with bleeding disorders and to generate some practical recommendations for clinicians.

MATERIAL AND METHODS

Pubmed/MEDLINE, Scopus, Web of Science and Cochrane Library databases were screened. The latest search was performed in July 2022. Case reports, case series, cohort studies, cross-sectional studies, case control studies, reviews, consensus reports, surveys and animal studies were included in the analysis.

RESULTS

Seventeen articles on CCDs were found, fourteen on APBDs and twenty-six on ACBDs. Most of these articles were case reports or case series. Patients with CCDs can be treated after the infusion of the missing coagulation factor. Patients with APBDs can be treated without withdrawing the therapy. Patients with ACBDs should be treated depending on the anticoagulative medication.

CONCLUSION

Despite the low level of evidence, dental implants can be safely placed in patients with bleeding disorders. However, careful preoperative evaluation and the adoption of local and post-operative bleeding control measures are mandatory.

Non-traumatic extraocular muscle haemorrhage associated with anticoagulation use

We present a case of a unilateral extraocular muscle haematoma in an adult female patient who was compliant with life-long oral anticoagulation for recurrent deep vein thrombosis. The patient presented with symptoms of sudden-onset left-sided headache radiating to the temporal region, which started 2 days prior. No obvious triggering factors were identified. Cranial and ocular examinations were within normal limits. Imaging revealed a haemorrhage related to the lateral rectus muscle of the left eye. Conservative management was employed with abstinence from anticoagulation for 2 weeks and a weaning regime of oral steroids. Under the clinical review of ophthalmology and interval radiological monitoring, symptoms were reduced with reduction of haemorrhage size. Anticoagulation was reinstated after 2 weeks. To our knowledge, this is the first case of a non-traumatic extraocular muscle haematoma to be reported in a patient on anticoagulation.

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.

American Journal of Preventive Cardiology: Area Deprivation Index and Oral Anticoagulation in New Onset Atrial Fibrillation

Objective

Oral anticoagulation is a standard of care for thromboembolic stroke prevention in individuals with atrial fibrillation (AF). Social determinants of health have had limited investigation in AF and particularly in access to anticoagulation. We examined the relation between area deprivation index (ADI) and anticoagulation in individuals at risk of stroke due to AF.

Methods

We conducted a retrospective analysis of patients with incident, non-valvular AF from 2015-2020 receiving care at a large, regional health center. We extracted demographics, medications, and problem lists and used administrative coding to identify comorbid conditions and relevant covariates, and individual-level residential address to ascertain ADI. We examined the relation between ADI and receipt of prescribed oral anticoagulation (warfarin or direct-acting oral anticoagulant, or DOAC) at 90 days following AF diagnosis in multivariable-adjusted models.

Results

Following exclusions, the dataset included 20,210 individuals (age 74.5±10.9 years; 51% women; 94% white race). In multivariable-adjusted analyses, individuals in the highest quartile of ADI had a 16% lower likelihood of receiving anticoagulation prescription than those in the lowest ADI quartile (Odds Ratio [OR] 0.84; 95% Confidence Interval [CI], 0.75-0.95) at 90 days following AF diagnosis. In those receiving anticoagulation, individuals in the highest ADI quartile had a 24% lower likelihood of receiving a DOAC prescription as opposed to warfarin prescription than those in the lowest quartile (OR 0.76; 95% CI, 0.60-0.96) at 90 days following AF diagnosis.

Conclusions

We demonstrate the association of higher neighborhood deprivation as determined by ADI with decreased likelihood of (1) anticoagulation prescribing for stroke prevention in AF and (2) prescription of a DOAC when any oral anticoagulation is prescribed. Our results suggest neighborhood-based health inequities in the receipt of anticoagulation prescription for stroke prevention in AF in a large, regional health care system.

Anticoagulation in COVID-19: current concepts and controversies

Rising incidence of thromboembolism secondary to COVID-19 has become a global concern, with several surveys reporting increased mortality rates. Thrombogenic potential of the SARS-CoV-2 virus has been hypothesised to originate from its ability to produce an exaggerated inflammatory response leading to endothelial dysfunction. Anticoagulants have remained the primary modality of treatment of thromboembolism for decades. However, there is no universal consensus regarding the timing, dosage and duration of anticoagulation in COVID-19 as well as need for postdischarge prophylaxis. This article seeks to review the present guidelines and recommendations as well as the ongoing trials on use of anticoagulants in COVID-19, identify discrepancies between all these, and provide a comprehensive strategy regarding usage of these drugs in the current pandemic.

Safety and efficacy of Direct Oral Anticoagulants in cerebral venous thrombosis: A meta-analysis

Cerebral venous thrombosis (CVT) is caused by partial or complete occlusion of the major cerebral venous sinuses or the smaller feeding cortical veins which predispose to the risk of venous infarction and hemorrhage. Current guidelines recommend treating CVT with either low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) followed by an oral vitamin K antagonist (VKA) for 3-12 months. Direct oral anticoagulants (DOACs) have already established benefit over warfarin as a long-term treatment of symptomatic venous thromboembolic disorder like deep vein thrombosis (DVT), and pulmonary embolism (PE) given its equal efficacy and better safety profile. The benefit of DOACs over warfarin as a long-term anticoagulation for CVT has likewise been extensively studied, yet it has not been approved as first-line therapy in the current practice. We therefore performed a systematic review and meta-analysis of relevant studies to generate robust evidence regarding the safety and efficacy of DOACs in CVT. This meta-analysis demonstrates that the use of DOACs in CVT has similar efficacy and safety compared to VKAs with better recanalization rate.

Currently available drugs for the treatment of Coronavirus-2

The Coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome Coronavirus 2 (SARS CoV-2) has created a never-before-seen problem for humanity. The world was pushed into a position where we needed to identify the effective drugs for a disease that has unknown characteristics in the early 2020s. SARS CoV-2 Virology research suggested that several drugs could be the potential targets. Remdesivir was the first drug that was shown to have promising results in in vitro studies. Remdesivir became the first antiviral drug approved by USFDA for the management of COVID-19. But later studies show equivocal results.

For this entirely new disease, we are still searching the perfect drug. Many existing drugs have been repurposed (steroids, anticoagulation, hydroxychloroquine) with varying success. Many new drugs have been researched for the management of this menace. In this review, we will discuss the mechanisms, uses, dosage, duration, and adverse effects of drugs used in COVID-19.

Direct oral anticoagulant dose selection: Challenging cases

Direct oral anticoagulants (DOACs) are given in fixed doses without routine laboratory monitoring of their anticoagulant effect based on the results of pivotal phase III trials. In some of these trials, patients were randomly allocated to receive a higher or lower dose of a DOAC, whereas in others, most patients were given a standard dose and only a subset deemed to be at risk of drug accumulation was given a lower dose. Treatment guidelines recommend dosing DOACs according to the way that they were tested in the trials, but for some patients, the optimal dosing remains uncertain. One example is patients with atrial fibrillation who are thought to have an unacceptably high risk of bleeding but do not meet the guideline criteria for dose reduction. A second is patients with venous thromboembolism who have completed 3 to 6 months of anticoagulation and are eligible for extended treatment with a standard or reduced dose of DOAC. In this review, we present a case-based approach to DOAC dose selection in these two settings.

Venous thrombosis recurrence risk according to warfarin versus direct oral anticoagulants for the secondary prevention of venous thrombosis

BACKGROUND

Venous thromboembolism (VTE) affects nearly 1 million Americans annually, and many benefit from continued anticoagulation after the initial 3- to 6-month treatment period (secondary prevention).

OBJECTIVES

To determine whether warfarin, apixaban, or rivaroxaban is associated with reduced recurrent VTE hospitalization in the secondary prevention of VTE.

PATIENTS/METHODS

We performed a retrospective cohort study of participants enrolled in the MarketScan Insurance Database between 2013 and 2017 in those with an incident VTE. In those individuals who continued oral anticoagulation (warfarin, apixaban, or rivaroxaban) beyond 6 months, we determined the relative rate of recurrent VTE hospitalization.

RESULTS

Among 119 964 individuals with VTE, 25 419 remained on anticoagulation after 6 months and were matched successfully by age, sex, and date. After adjusting for a propensity score, apixaban versus rivaroxaban (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.45-0.94) and apixaban versus warfarin (HR, 0.68; 95% CI, 0.47-1.00) had a reduced risk of recurrent VTE hospitalization, and rivaroxaban versus warfarin (HR, 1.12; 95% CI, 0.94-1.33) had equivalent rates. For the rivaroxaban versus warfarin comparison there was a significant interaction by renal function (P < .01) where rivaroxaban was associated with a lower risk of recurrent VTE hospitalization (HR, 0.65; 95% CI, 0.41-1.03) in those with kidney disease and increased risk in those without kidney disease (HR, 1.24; 95% CI, 1.02-1.50).

CONCLUSIONS

These data suggest that apixaban has a lower recurrent VTE hospitalization rate than rivaroxaban during the secondary prevention of VTE, and further study of diverse patient populations, especially by kidney function, is warranted.

Review Article: Gastrointestinal Bleeding Risk with Direct Oral Anticoagulants

PURPOSE

Although direct oral anticoagulants (DOACs) are associated with an overall favourable safety profile, the risk of gastrointestinal bleeding with DOACs compared with vitamin K antagonists (VKAs) remains controversial. Accordingly, we aimed to provide a focused overview of the risk of gastrointestinal bleeding associated with dabigatran, rivaroxaban, apixaban and edoxaban and its management.

METHODS

We reviewed published studies reporting on DOACs with gastrointestinal bleeding as an outcome, including randomised controlled trials (RCTs), retrospective database studies and large-scale prospective cohort studies.

RESULTS

Cumulative evidence confirms no notable difference in major gastrointestinal bleeding risk between DOACs and VKAs. Moreover, gastrointestinal bleeding in DOAC-treated patients seems less severe and requires less intensive management. The main cause of upper gastrointestinal bleeding in DOAC-treated patients appears to be gastroduodenal ulcers, whereas lower gastrointestinal bleedings are mainly due to diverticula followed by angiodysplasia and haemorrhoids. The lack of head-to-head RCTs with DOACs precludes drawing conclusions on the DOAC with the lowest gastrointestinal bleeding risk. Prescribing physicians should be aware of risk factors for DOAC-related gastrointestinal bleeding (e.g. age > 65, heavy alcohol use, uncontrolled hypertension, hepatic or renal dysfunction, active cancer, anaemia) and adopt preventive measures accordingly. Management of DOAC-associated major gastrointestinal bleeding involves temporary discontinuation of the DOAC, investigation of the bleeding source and treatment of bleeding with fluid resuscitation combined with transfusion and endoscopic haemostasis.

CONCLUSION

DOACs as a class do not increase the risk of major gastrointestinal bleeding compared to VKAs, which supports their continued use for different anticoagulant indications.

Real-world persistence to direct oral anticoagulants in patients with atrial fibrillation: a systematic review and network meta-analysis

OBJECTIVE

To conduct a systematic review and network meta-analysis of real-world evidence comparing adherence, persistence, cost, and utilization between oral anticoagulant (OAC) in non-valvular atrial fibrillation (NVAF) patients.

METHODS

A systematic search of MEDLINE and Embase (inception-July 2019) was conducted for published observational cohort studies comparing outcomes between ≥2 OACs. A network meta-analysis was performed to estimate odds ratios for non-persistence using a random-effects model.

RESULTS

There were 80 studies evaluating the outcomes of interest. However, due to a paucity in adherence studies and heterogeneity in adherence, cost, and utilization definitions, persistence was the focus of this network meta-analysis. There were 36 studies evaluating non-persistence in 395,593 participants, 24 of which used 3 gap definitions (30-, 60-, and 90-days); 18 unique studies evaluating non-persistence at 12 months were included in the network meta-analysis. Using 30- and 90-day gaps, all NOACs, when compared with VKAs, had lower odds of non-persistence (30-day OR (95%CI): apixaban: 0.63 (0.58, 0.69); rivaroxaban: 0.69 (0.62, 0.76); dabigatran: 0.89 (0.82, 0.97); 90-day OR (95%CI): apixaban: 0.33 (0.22, 0.47); rivaroxaban: 0.47 (0.36, 0.61); dabigatran 0.61 (0.44, 0.85)). When using a 60-day gap, dabigatran had higher odds of non-persistence vs VKAs (OR: 1.35; 95%CI: 1.12, 1.61), but there were no significant differences for apixaban and rivaroxaban. Apixaban had the lowest probability of non-persistence across the 3-gap definitions (95.7% with 30-day gap, 76.9% with 60-day gap, 98.4% with 90-day gap).

CONCLUSIONS

The current findings, despite multiple limitations, can raise awareness and understanding of real-world persistence associated with OAC therapy in NVAF patients.

Association of Risk of Dementia With Direct Oral Anticoagulants Versus Warfarin Use in Patients With Non-valvular Atrial Fibrillation: A Systematic Review and Meta-analysis

ABSTRACT

Atrial fibrillation (AF) is associated with an increased risk of dementia. Studies have shown the beneficial effects of anticoagulants in preventing dementia in this population. However, evidence around the use of direct oral anticoagulants (DOACs) versus warfarin in AF-related dementia prevention remains sparse. This systematic review and meta-analysis aimed to evaluate the use of DOACs versus warfarin in dementia prevention in this population. MEDLINE, EMBASE, PsycINFO, and the CENTRAL databases were systematically searched from its inception until May 2020. Nine studies (n = 611,069) were included for quantitative meta-analysis. DOACs use was associated with a lower risk of composite dementia outcomes compared with warfarin use [odds ratio (OR) 0.56, 95% confidence interval (CI) 0.34-0.94, P = 0.03]. No significant difference was found in subtypes of dementia (vascular dementia, Alzheimer's disease, and cognitive disorder) between both groups. No significant difference in the risk of composite dementia outcomes between the dabigatran and warfarin groups (OR 0.97, 95% CI 0.88-1.08, P = 0.61). Apixaban (OR 0.58, 95% CI 0.50-0.67, P < 0.00001) and rivaroxaban (OR 0.67, 95% CI 0.61-0.75, P < 0.00001) use were both associated with a significantly lower risk of composite dementia outcomes compared with warfarin use. Findings need to be interpreted with caution because of low certainty of evidence. In conclusion, this systematic review and meta-analysis of 9 comparative studies demonstrated the superiority of DOACs over warfarin in prevention of dementia in AF. Future prospective trials with adequate follow-up period are warranted to ascertain its causal relationship.

Use of real-world evidence in meta-analyses and cost-effectiveness models

Real-world evidence (RWE) provides external validity, supplementing and enhancing the randomized controlled trial data with valuable information on patient behaviors and outcomes, turning efficacy and safety results into real-world effectiveness and risks, but the use of RWE is associated with challenges. The objectives of this communication were to (1) summarize all guidance on how to conduct an RWE meta-analysis (MA) and how to develop an RWE cost-effectiveness model, (2) to describe our experience, challenges faced and solutions identified, (3) to provide recommendations on how to conduct such analyses. No formal guidelines on how to conduct an RWE MA or to develop an RWE cost-effectiveness model were identified. Using the context of non-vitamin K antagonist oral anticoagulants in stroke prevention in atrial fibrillation, we conducted an RWE MA, after having identified sources of uncertainty. We then implemented the results in an RWE cost-effectiveness model, defined as a model where all inputs come from RWE, including all parameters related to treatment effect. Based on challenges faced, our first recommendation relates to the necessity of conducting sensitivity analyses, either based on clinical or methodological considerations. Our second recommendation is the need for extensive collaboration with a wide range of experts, during the development of the analyses protocols, the implementation of the analyses and the interpretation of the results. RWE may address a number of gaps related to the treatment effect, and RWE economic evaluations for the treatment effect can provide extremely valuable insights into real-world economic value of interventions. As the increased recognition of the value of RWE could influence health technology assessment decision, and current practices, this communication supports the urgent need of more formal guidelines.

Real-world cost-effectiveness of rivaroxaban and apixaban vs VKA in stroke prevention in non-valvular atrial fibrillation in the UK

BACKGROUND

Morbidity and mortality associated with non-valvular atrial fibrillation (NVAF) imposes a substantial economic burden on the UK healthcare system.

OBJECTIVES

An existing Markov model was adapted to assess the real-world cost-effectiveness of rivaroxaban and apixaban, each compared with a vitamin K antagonist (VKA), for stroke prevention in patients with NVAF from the National Health Service (NHS) and personal and social services (PSS) perspective.

METHODS

The model considered a cycle length of 3 months over a lifetime horizon. All inputs were drawn from real-world evidence (RWE): baseline patient characteristics, clinical event and persistence rates, treatment effect (meta-analysis of RWE studies), utility values and resource use. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

The incremental cost per quality-adjusted life year was £14,437 for rivaroxaban, and £20,101 for apixaban, compared with VKA. The probabilities to be cost-effective compared with VKA were 90% and 81%, respectively for rivaroxaban and apixaban, considering a £20,000 threshold. In both comparisons, the results were most sensitive to clinical event rates.

CONCLUSIONS

These results suggest that rivaroxaban and apixaban are cost-effective vs VKA, based on RWE, considering a £20,000 threshold, from the NHS and PSS perspective in the UK for stroke prevention in patients with NVAF. This economic evaluation may provide valuable information for decision-makers, in a context where RWE is more accessible and its value more acknowledged.

A Delphi consensus on the management of oral anticoagulation in patients with non-valvular atrial fibrillation in Spain: ACOPREFERENCE study

OBJECTIVE

To evaluate the level of agreement between cardiologists regarding the management of oral anticoagulation (OAC) in patients with non-valvular atrial fibrillation (NVAF) in Spain.

MATERIALS AND METHODS

A two-round Delphi study was performed using an online survey. In round 1, panel members rated their level of agreement with the questionnaire items on a 9-point Likert scale. Item selection was based on acceptance by ≥66.6% of panellists and the agreement of the scientific committee. In round 2, the same panellists evaluated those items that did not meet consensus in round 1.

RESULTS

A total of 238 experts participated in round 1; of these, 217 completed the round 2 survey. In round 1, 111 items from 4 dimensions (Thromboembolic and bleeding risk evaluation for treatment decision-making: 18 items; Choice of OAC: 39 items; OAC in specific cardiology situations: 12 items; Patient participation and education: 42 items) were evaluated. Consensus was reached for 92 items (83%). Over 80% of the experts agreed with the use of DOACs as the initial anticoagulant treatment when OAC is indicated. Panellists recommended the use of DOACs in patients at high risk of thromboembolic complications (CHA2DS2-VASc ≥3) (83%), haemorrhages (HAS-BLED ≥3) (89%) and poor quality of anticoagulation control (SAMe-TT2R2 >2) (76%), patients who fail to achieve an optimal therapeutic range after 3 months on VKA treatment (93%), and those who are to undergo cardioversion (80%). Panellists agreed that the efficacy and safety profile of each DOAC (98%), the availability of a specific reversal agent (72%) and patient's preference (85%) should be considered when prescribing a DOAC. A total of 97 items were ultimately accepted after round 2.

CONCLUSIONS

This Delphi panel study provides expert-based recommendations that may offer guidance on clinical decision-making for the management of OAC in NVAF. The importance of patient education and involvement has been highlighted.

Rivaroxaban Versus Apixaban for Stroke Prevention in Atrial Fibrillation

Background:

The comparative effectiveness of non-vitamin K antagonist oral anticoagulants (NOACs) is uncertain, as they have not been compared directly in randomized trials. Previous observational comparisons of NOACs are likely to be biased by unmeasured confounders. We sought to compare the efficacy and safety of rivaroxaban and apixaban for stroke prevention in patients with atrial fibrillation (AF), using practice variation in preference for NOAC as an instrumental variable.

Methods and Results:

Patients started on apixaban or rivaroxaban after newly diagnosed AF were identified using Danish nationwide registries. Patients were categorized according to facility preferences for type of NOAC, independent of actual treatment, measured as fraction of the prior 20 patients with AF initiated on rivaroxaban in the same facility. Facility preference for NOAC was used as an instrumental variable. The occurrence of stroke/thromboembolism, major bleeding, myocardial infarction, and all-cause mortality over 2 years of follow-up were investigated using adjusted Cox regressions. We analyzed 6264 patients with AF initiated on rivaroxaban or apixaban. NOAC preference was strongly related to actual choice of treatment but not associated with any other measured baseline characteristics. Patients treated in facilities that had preference for rivaroxaban had more major bleeding: compared with patients treated in facilities that used rivaroxaban in 0% to 20% of cases, the adjusted hazard ratio for bleeding was 1.06 when treated in a facility with 25% to 40% use; 1.41 with 45% to 60% use; 1.51 with 65% to 80% use; and 1.81 with 0% to 100% use ( P trend =0.01). Higher facility preference for rivaroxaban was not significantly associated with increased risk of stroke/thromboembolism ( P trend =0.06), myocardial infarction ( P trend =0.65), or all-cause mortality ( P trend =0.89). When we used the instrumental variable to model the causal relationship between choice of NOAC and major bleeding, relative risk with rivaroxaban was 1.89 (95% CI, 1.06–2.72) compared with apixaban.

Conclusions:

Using instrumental variable estimation in a cohort of patients with AF, rivaroxaban was associated with higher risk of major bleeding compared with apixaban. No significant associations to other outcomes were found in main analyses.

Temporal Trends and Patient Characteristics Associated With Drug Utilisation After First-Ever Stroke: Insights From Chronic Disease Registry Data in Singapore

Introduction: Data on drug utilisation among stroke patients of Asian ethnicities are lacking. The objectives of the study were to examine the temporal trends and patient characteristics associated with prescription of thrombolytic, antithrombotic and statin medications among patients with first-ever stroke. Materials and Methods: First-ever ischaemic and haemorrhagic stroke patients admitted to 2 Singapore tertiary hospitals between 2010‒2014 were included. Data were extracted from the National Healthcare Group Chronic Disease Management System. Association between drug utilisation and admission year, as well as characteristics associated with drug use, were explored using multivariable logistic regression. Results: There was an increasing trend in the combined use of all 3 guideline medications in ischaemic stroke patients (P<0.001) ―specifically thrombolytic agents (P <0.001), oral antithrombotics (P = 0.002) and statins (P = 0.003) at discharge. Among antithrombotics, the use of clopidogrel (P <0.001) and aspirinclopidogrel (P <0.001) had increased, whereas prescription of dipyridamole (P <0.001) and aspirin-dipyridamole (P <0.001) had declined. For statins, the increase in atorvastatin prescription (P <0.001) was accompanied by decreasing use of simvastatin (P <0.001). Age, ethnicity and certain comorbidities (hyperlipidaemia, atrial fibrillation and chronic kidney disease) were associated with the combined use of all 3 guideline medications (P <0.05). In haemorrhagic stroke, prescription of statins at discharge were comparatively lower. Conclusion: This study reveals changes in prescription behaviour over time in a multiethnic Asian population with first-ever stroke. Patient characteristics including younger age, Malay ethnicity and certain comorbidities (i.e. hyperlipidaemia, atrial fibrillation) were associated with the combined use of all 3 guideline medications among ischaemic stroke patients. Key words: Antithrombotics, Asian, Statins, Thrombolytic agents

Practical guide to choosing dabigatran 150 mg twice daily or apixaban 5 mg twice daily for patients with atrial fibrillation

Based on previous reports, we propose a practical guide to choose dabigatran 150 mg twice daily or apixaban 5 mg twice daily for patients with atrial fibrillation. We recommend the use of dabigatran 150 mg twice daily for patients with atrial fibrillation who have a high risk of embolism (e.g., ischemic stroke on other oral anticoagulants, presence of left atrial appendage thrombus) and a low risk of bleeding. However, the prevalence of such patients with atrial fibrillation is considered low because patients with atrial fibrillation with a high risk of embolism usually have a high risk of bleeding. In most other patients with atrial fibrillation, the use of apixaban 5 mg twice daily should be considered.

DOACs vs Vitamin K Antagonists: a Comparison of Phase III Clinical Trials and a Prescriber Support Tool

AIM:

The purpose of this article was to systematically review the literature assessing the efficacy and safety of phase III clinical trials for each direct oral anticoagulant versus vitamin K antagonists and to design a “go-to” table for the prescriber.

MATERIAL AND METHODS:

A systematic review of specialist literature was conducted to identify RCTs which compared direct oral anticoagulants (DOACs) with standard warfarin treatment. Medline, Em-base, and the Cochrane databases were searched from January 2005- January 2019. The inclusion criteria were randomised controlled trials of oral anticoagulants in patients with non-valvular atrial fibrillation (NVAF). Four publications were phase III randomised control trials (RCTs) included in the final analysis.

RESULTS:

Regarding the primary outcome in RELY the results were 1.69% per 100-year patients (p/y) for Warfarin compared to 1.11% p/y dabigatran etexilate 150mg BD (twice daily). In ROCKET AF the rates of the primary outcome were 2.2% p/y for warfarin compared to 1.7% p/y for rivaroxaban 20 mg OD (once daily). In ARISTOTLE trial the rates of the primary outcome were 1.60% p/y for warfarin compared to 1.27% p/y for apixaban 5 mg BD. In ENGAGE AF TIMI, the rates of the primary outcome were 1.50% p/y for warfarin compared to 1.18% p/y for edoxaban 60mg BD.

CONCLUSION:

DOACs showed to be either noninferior or superior to warfarin with regards to the primary outcome with better safety patterns. Our “go-to” table provides a supportive tool for physicians in preventing medical errors when managing patients on oral anticoagulants.

Hemorrhagic Cardiac Tamponade Associated with Apixaban: A Case Report and Systematic Review of Literature

BACKGROUND

Hemorrhagic cardiac tamponade (HCT) is characterized by rapid accumulation of blood in the pericardium causing hemodynamic collapse. We report a case of HCT due to Apixaban use in a patient with renal cell carcinoma, supplemented with a systematic review of pericardial tamponade associated with the use of direct oral anticoagulants (DOACs).

CASE REPORT

A 62-year-old African American male with a history of metastatic renal cell carcinoma presented with dyspnea while taking Apixaban. He was diagnosed with pericardial tamponade and 800 ml of hemorrhagic effusion was drained. The pericardial fluid analysis was negative for malignancy and suggestive of HCT. He had a complicated hospital course and died several days later.

METHODS

We searched MEDLINE, EMBASE and other sources for published cases of pericardial tamponade associated with DOACs. Our outcomes of interest included patient characteristics, risk factors, timing from the start of anticoagulation to tamponade, treatment and mortality. Simple descriptive statistics using percentages for categorical variables were used to describe the included cases.

RESULTS

A total of 26 cases were included in the final systematic review after searching MEDLINE, EMBASE and other sources. The mean age was 70 years (range 43-88) with 19 (73%) males. Twelve cases (46%) were associated with Rivaroxaban, 9 (37%) with Dabigatran and 5(19%) with Apixaban. Sixteen cases had elevated INR and 15 had elevated creatinine. Only 2 patients died but 24 had to undergo pericardiocentesis.

CONCLUSION

Cardiac tamponade is rarely associated with DOACs and elderly male patients with renal and coagulation abnormalities appear to have the highest risk.

Association of Adding Aspirin to Warfarin Therapy Without an Apparent Indication With Bleeding and Other Adverse Events

IMPORTANCE

It is not clear how often patients receive aspirin (acetylsalicylic acid) while receiving oral anticoagulation with warfarin sodium without a clear therapeutic indication for aspirin, such as a mechanical heart valve replacement, recent percutaneous coronary intervention, or acute coronary syndrome. The clinical outcomes of such patients treated with warfarin and aspirin therapy compared with warfarin monotherapy are not well defined to date.

OBJECTIVE

To evaluate the frequency and outcomes of adding aspirin to warfarin for patients without a clear therapeutic indication for combination therapy.

DESIGN, SETTING, AND PARTICIPANTS

A registry-based cohort study of adults enrolled at 6 anticoagulation clinics in Michigan (January 1, 2010, to December 31, 2017) who were receiving warfarin therapy for atrial fibrillation or venous thromboembolism without documentation of a recent myocardial infarction or history of valve replacement.

EXPOSURE

Aspirin use without therapeutic indication.

MAIN OUTCOMES AND MEASURES

Rates of any bleeding, major bleeding events, emergency department visits, hospitalizations, and thrombotic events at 1, 2, and 3 years.

RESULTS

Of the study cohort of 6539 patients (3326 men [50.9%]; mean [SD] age, 66.1 [15.5] years), 2453 patients (37.5%) without a clear therapeutic indication for aspirin were receiving combination warfarin and aspirin therapy. Data from 2 propensity score-matched cohorts of 1844 patients were analyzed (warfarin and aspirin vs warfarin only). At 1 year, patients receiving combination warfarin and aspirin compared with those receiving warfarin only had higher rates of overall bleeding (cumulative incidence, 26.0%; 95% CI, 23.8%-28.3% vs 20.3%; 95% CI, 18.3%-22.3%; P < .001), major bleeding (5.7%; 95% CI, 4.6%-7.1% vs 3.3%; 95% CI, 2.4%-4.3%; P < .001), emergency department visits for bleeding (13.3%; 95% CI, 11.6%-15.1% vs 9.8%; 95% CI, 8.4%-11.4%; P = .001), and hospitalizations for bleeding (8.1%; 6.8%-9.6% vs 5.2%; 4.1%-6.4%; P = .001). Rates of thrombosis were similar, with a 1-year cumulative incidence of 2.3% (95% CI, 1.6%-3.1%) for those receiving combination warfarin and aspirin therapy compared with 2.7% (95% CI, 2.0%-3.6%) for those receiving warfarin alone (P = .40). Similar findings persisted during 3 years of follow-up as well as in sensitivity analyses.

CONCLUSIONS AND RELEVANCE

Compared with warfarin monotherapy, receipt of combination warfarin and aspirin therapy was associated with increased bleeding and similar observed rates of thrombosis. Further research is needed to better stratify which patients may benefit from aspirin while anticoagulated with warfarin for atrial fibrillation or venous thromboembolism; clinicians should be judicious in selecting patients for combination therapy.

Pharmacogenomics of Novel Direct Oral Anticoagulants: Newly Identified Genes and Genetic Variants

Direct oral anticoagulants (DOAC) have shown an upward prescribing trend in recent years due to favorable pharmacokinetics and pharmacodynamics without requirement for routine coagulation monitoring. However, recent studies have documented inter-individual variability in plasma drug levels of DOACs. Pharmacogenomics of DOACs is a relatively new area of research. There is a need to understand the role of pharmacogenomics in the interpatient variability of the four most commonly prescribed DOACs, namely dabigatran, rivaroxaban, apixaban, and edoxaban. We performed an extensive search of recently published research articles including clinical trials and in-vitro studies in PubMed, particularly those focusing on genetic loci, single nucleotide polymorphisms (SNPs), and DNA polymorphisms, and their effect on inter-individual variation of DOACs. Additionally, we also focused on commonly associated drug-drug interactions of DOACs. CES1 and ABCB1 SNPs are the most common documented genetic variants that contribute to alteration in peak and trough levels of dabigatran with demonstrated clinical impact. ABCB1 SNPs are implicated in alteration of plasma drug levels of rivaroxaban and apixaban. Studies conducted with factor Xa, ABCB1, SLCOB1, CYP2C9, and VKORC1 genetic variants did not reveal any significant association with plasma drug levels of edoxaban. Pharmacokinetic drug-drug interactions of dabigatran are mainly mediated by p-glycoprotein. Strong inhibitors and inducers of CYP3A4 and p-glycoprotein should be avoided in patients treated with rivaroxaban, apixaban, and edoxaban. We conclude that some of the inter-individual variability of DOACs can be attributed to alteration of genetic variants of gene loci and drug-drug interactions. Future research should be focused on exploring new genetic variants, their effect, and molecular mechanisms that contribute to alteration of plasma levels of DOACs.

Pharmacokinetics and Pharmacodynamics of an Oral Formulation of Apixaban in Horses After Oral and Intravenous Administration

Horses with inflammatory and infectious disorders are often treated with injectable heparin anticoagulants to prevent thrombotic complications. In humans, a new class of direct oral acting anticoagulants (DOAC) appear as effective as heparin, while eliminating the need for daily injections. Our study in horses evaluated apixaban, a newly approved DOAC for human thromboprophylaxis targeting activated factor X (Xa). Our goals were to: (1) Determine pharmacokinetics and pharmacodynamics of apixaban after oral (PO) and intravenous (IV) administration in horses; (2) Detect any inhibitory effects of apixaban on ex vivo Equid herpesvirus type 1 (EHV-1)-induced platelet activation, and (3) Compare an anti-Xa bioactivity assay with ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) for measuring apixaban concentrations. In a blinded placebo-controlled cross-over study, five horses received a single dose (0.2 mg/kg) of apixaban or placebo PO or IV. Blood was collected before and at 3 (IV) or 15 (PO) min, 30 and 45 min, and 1, 2, 3, 4, 6, 8, and 24 h after dosing for measuring apixaban UPLC-MS concentrations and anti-Xa activity. Pharmacodynamic response was measured in a dilute prothrombin time (dPT) assay. Flow cytometric EHV-1-induced platelet P-selectin expression and clinical pathologic safety testing were performed at baseline, 2 and 24 h and baseline and 24 h, respectively. We found no detectable apixaban in plasma PO administration. After IV administration, plasma apixaban levels followed a two-compartment model, with concentrations peaking at 3 min and decreasing to undetectable levels by 8 h. The elimination half-life was 1.3 ± 0.2 h, with high protein binding (92–99%). The dPT showed no relationship to apixaban UPLC-MS concentration and apixaban did not inhibit EHV-1-induced platelet activation after IV dosing. Apixaban anti-Xa activity showed excellent correlation to UPLC-MS (r² = 0.9997). Our results demonstrate that apixaban has no apparent clinical utility as an anticoagulant for horses due to poor oral availability.

Approaches to Direct Oral Anticoagulant Selection in Practice

Direct oral anticoagulants (DOACs) carry many advantages over warfarin and are now considered first line or an alternative for mnay thromboembolic disorders. With the emergence of 5 DOAC agents to the market as well as the accumulating evidence gathered from head-to-head comparisons between the agents, we attempt to provide direction for clinicians when selecting the most appropriate DOAC agent. Important aspects such as efficacy, safety, cost effectiveness, approved indications, and other drug-related factors will be addressed to highlight the major similarities and diversities among the DOACs. When considering the safety profile of DOACs, evidence points toward apixaban as the safest followed by dabigatran and then rivaroxaban. On the other hand, dabigatran currently has the only approved antidote, idarucizumab. According to the approved DOAC indications, rivaroxaban may be favorable in European countries given its additional indication for secondary prevention of myocardial infarction. Following rivaroxaban, dabigatran and apixaban have the largest number of approved indications and lastly comes edoxaban and then betrixaban. For patients with renal impairment, betrixaban is the safest option, followed by apixaban and edoxaban, then rivaroxaban and lastly dabigatran. When considering DOAC dosing, rivaroxaban, edoxaban, and betrixaban are mainly dosed once daily compared to dabigatran and apixaban, which are dosed twice daily. However, rivaroxaban and betrixaban must be administered with food, which adds another level of complexity to the DOAC dosing. Lastly, taking into consideration drug interactions, dabigatran, edoxaban, and betrixaban have the least amount of interactions compared to apixaban and rivaroxaban. Each DOAC has its own set of features that makes it better suited than others based on the exact clinical situation. Therefore, no conclusion can be drawn to the most superior DOAC based on the aspects discussed in this review.

Evaluation of Potential Drug-Drug Interactions With Direct Oral Anticoagulants in a Large Urban Hospital

OBJECTIVE

The aim of this study is to assess patterns of potential drug-drug interactions (DDIs) with direct oral anticoagulants (DOACs) in an inpatient hospital setting.

METHODS

A retrospective chart review was conducted at the Brookdale University Hospital and Medical Center (BUHMC) from January 2014 to November 2016. All adult patients admitted to the BUHMC who were treated with a DOAC for at least 3 days were screened. Among them, those who received selected interacting drugs at any time during the course of DOAC therapy were included in this study.

RESULTS

This study included 165 patients with an average of 73 years (standard deviation [SD] = 12.3) and 233 cases. The most commonly used concomitant drug with a DOAC was aspirin (58%), followed by amiodarone (16%) and P2Y₁₂ inhibitors (11%). The combined use of dual antiplatelet therapy and a DOAC was identified in 18 (6%) cases. Approximately one-third of the cases encountered were classified as the "avoidance" category.

CONCLUSIONS

Despite computerized DDI alerts, potentially significant DDIs with DOACs still occur. While the present study provides insight into the current patterns of DDIs, further studies are needed to evaluate clinical outcomes of the potential DDIs with DOACs in practice.

Incidence of Visible Hematuria Among Antithrombotic Agents: A Systematic Review of Over 175,000 Patients

OBJECTIVE

To determine the probability of visible hematuria with antithrombotic agents and to evaluate association of urologic etiology in antithrombotic-related hematuria.

METHODS

Preferred Reporting Items in Systematic Reviews and Meta-Analyses guidelines were followed to conduct a systematic review using search engines PUBMED and SCOPUS with the terms "(hematuria) OR (haematuria) OR urinary bleeding)) AND ((anticoagulants) OR anticoagulation) OR noac) OR novel anticoagulants) OR antiplatelet) OR dabigatran) OR rivaroxaban) OR apixaban) OR warfarin) OR aspirin) OR heparin) OR dipyridamole)." Raw data were used to perform a pooled analysis. Chi-square and logistic regression analysis were used for statistical analyses.

RESULTS

Twenty-two studies describing 175,114 patients met inclusion criteria. Odds ratio of hematuria with warfarin to rivoraxaban was 33 and warfarin to dabigatran was 16. The odds ratio of hematuria for oral anticoagulant (26.7%) to prophylactic parenteral anticoagulant (1.1%) agents was 9.6. Antiplatelet agents are 76 times less likely to cause hematuria compared to anticoagulants. Odds of hematuria with aspirin were 6.7 times the odds with clopidogrel and 3.5 times the odds with ticagrelor. Dabigatran was 198 times more likely to cause major hematuria compared to warfarin, whereas clopidogrel is 1.2 times more likely to cause major hematuria compared to aspirin. Urologic pathology was identified in 44% (234/532) of cases, malignancy in 24%.

CONCLUSION

Warfarin use poses the greatest risk for hematuria but is unlikely to cause major hematuria, whereas novel antithrombotic agents are more commonly associated with major hematuria. This review further characterizes the risk profile of antithrombotic agents and associated hematuria to equip clinicians with knowledge to choose an appropriate antithrombotic agent in patients with high-risk hematuria.

Sociodemographic factors in patients continuing warfarin vs those transitioning to direct oral anticoagulants

Clinical factors and patient preferences are important for selecting oral anticoagulants for venous thromboembolism (VTE) and atrial fibrillation (AF). The relative association of sociodemographic factors with anticoagulant use is unknown. We evaluated a prospective cohort to compare sociodemographic variables in patients who continued on warfarin for AF or VTE to those who transitioned to 1 of the direct oral anticoagulants (DOACs). Adult patients, newly started on warfarin, were enrolled through 6 anticoagulation clinics across Michigan. Of 8468 patients, 53.3% had AF, 45.6% had VTE, and 1.1% had both. Of these, 696 (8.2%) switched from warfarin to a DOAC. There were no significant differences between switchers and nonswitchers for percentage of time with a therapeutic international normalized ratio on warfarin, urban-rural residence status, or health insurance. Switchers were more often white (83.3% vs 77.7%; P < .001), partnered (67.3% vs 59.2%; P < .001), or resided in a zip code with a higher median household income (P < .001). The results show that sociodemographic factors, such as race, partnered status, and income are associated with a patient's likelihood of switching to a DOAC vs remaining on warfarin therapy. Although clinical factors predominate, the reason for, and impact of, these observed variations in care requires further investigation.

New frontiers in anticoagulation: non vitamin-K oral anticoagulants in stroke prevention

INTRODUCTION

Non vitamin-K oral anticoagulants (NOACs) are direct and specific inhibitors of the coagulation factors IIa (dabigatran) and Xa (apixaban, rivaroxaban, edoxaban) which share many pharmacokinetic properties. However, indications are lacking regarding the use of NOACs during thrombolysis, surgery and bleeding events. Areas covered: In this paper, the authors retrospectively analyzed the relevant literature on the NOACs using the PubMed and Google Scholar databases. Expert commentary: Although warfarin is effective in cardioembolic stroke prevention, easier handling and more favorable risk-benefit profile often render NOACs a more preferable therapy choice for neurologists. New evidences have suggested their use in treatment of elderly people, in patients with renal insufficiency or with antiphospholipid antibody syndrome. In addition, the use of antidotes, which rapidly reverse the anticoagulant effect of the NOACs, could be useful in bleeding, during emergency procedures, or in case of overdose.

[Use of non-vitamin K antagonist oral anticoagulants in Primary Care: ACTUA study]

OBJECTIVES

Approximately 40% of patients with non-valvular auricular fibrillation (NVAF) who receive vitamin K antagonists (VKA) in Primary Care in Spain have poor anticoagulation control. The objective of the study Actuación en antiCoagulación, Tratamiento y Uso de anticoagulantes orales de acción directa (ACOD) en Atención primaria (ACTUA) (Action in Coagulation, Treatment and Use of direct oral anticoagulants [DOACs]) in Primary Care) was to analyse the current situation regarding the use of VKA and non-vitamin K antagonist oral anticoagulants (NOACs) in patients with NVAF in Primary Care in Spain and the possible issues arising from it.

PATIENTS AND METHODS

An online survey was created covering various aspects of the use of oral anticoagulants in NAFV. A two-round modified Delphi approach was used. Results were compiled as a set of practical guidelines.

RESULTS

Forty-four experts responded to the survey. Consensus was reached in 62% (37/60) of the items. Experts concluded that a considerable number of patients with NVAF who receive VKA do not have a well-controlled INR and that a substantial group of patients who could benefit from being treated with NOACs do not receive them. The use of NOACs increases the probability of having good anticoagulation control and decreases the risk of severe and intracranial haemorrhage. Current limitations to the use of NOACs include administrative barriers, insufficient knowledge about the benefits and risks of NOACs, limited experience of doctors in using them, and their price. Renal insufficiency influences the choice of a particular anticoagulant.

CONCLUSIONS

The ACTUA study highlights the existing controversies about the use of oral anticoagulants for the treatment of NVAF in Primary Care in Spain, and provides consensus recommendations that may help to improve the use of these medications.

New Oral Anticoagulants in Nonvalvular Atrial Fibrillation

The choice of an oral anticoagulant (OAC) for patients with nonvalvular atrial fibrillation (NVAF) is a major and complex clinical decision taking into account the individual risk-benefit ratio and bearing in mind the chronicity of therapy. This review focuses on the safety and efficacy of new oral anticoagulants (NOACs) compared with conventional vitamin K antagonists (VKA) in patients with NVAF. Current data suggest that NOACs are at least as effective and safe as VKAs for most NVAF subjects. The NOACs do not mandate dietary restrictions and regular pharmacodynamic monitoring, and they seem to have lesser incidence of intracranial or fatal bleeding when compared with VKAs. However, both dabigatran 150 twice daily and rivaroxaban have a slightly higher incidence of gastrointestinal bleeding when compared with VKAs. The article will delineate the current knowledge as well as scientific gaps related to the choice and dosage of anticoagulation regimens for various NVAF subsets and will address certain common clinical scenarios requiring special considerations. The article also addresses the shortcomings of NOACs: lack of therapeutic pharmacokinetic and pharmacodynamic targets, absence of tools to assess compliance and efficacy, rigid and limited dosage options, and absence of effective and inexpensive reversal agents.

Overcoming global challenges in stroke prophylaxis in atrial fibrillation: The role of non-vitamin K antagonist oral anticoagulants

Atrial fibrillation is the world's most common sustained cardiac arrhythmia and is associated with a significantly increased risk of stroke. The global burden of atrial fibrillation is rising, commensurate with the ageing population. Well-controlled vitamin K antagonist-based anticoagulation has been shown to reduce the risk of stroke secondary to atrial fibrillation by two-thirds. However, patients with atrial fibrillation have frequently been denied anticoagulation because of a variety of perceived risks related to bleeding, falls, chronological age, and poor compliance. Even when vitamin K antagonists are used, maximum benefit and safety are only delivered when high quality control of therapy (TTR > 70%) is achieved, which has proven remarkably difficult in many health-care systems and amongst many patient groups. The non-vitamin K antagonist oral anticoagulants (NOACs) offer solutions to many of the challenges of achieving widespread, safe, and effective anticoagulation for stroke prophylaxis in atrial fibrillation, yet their uptake into routine clinical practice remains variable. The evidence supporting their more widespread use to overcome the challenges of stroke prophylaxis for atrial fibrillation is reviewed in this article.

DOACs - advances and limitations in real world

The group of new oral anticoagulants or NOACs, now termed direct oral anticoagulants or DOACs, with their favourable results from large scale phase III clinical trials, represent a major advancement and expanded armamentarium in antithrombotic therapy. Dabigatran, rivaroxaban, apixaban and edoxaban are now in clinical routine use for prevention and treatment of arterial and venous thrombotic diseases as addressed in their clinical trials. Usage of the DOACs is expected to increase as clinicians gain more experience and reassurance with data from the real world studies which are generally consistent with that from clinical trials. Development of specific antidotes in management of bleeding complications and development of coagulation assays for their plasma levels will further boost the confidence in the DOACs. Nonetheless, there are still limitations associated with the DOACs. Many patients in need of anticoagulant therapy for indications not studied in the clinical trials will not be eligible for treatment with a DOAC. Conditions where more data is required include DOACs use in the paediatric age group, patients with atrial fibrillation and valvular heart disease, thrombosis associated with the anti-phospholipid syndrome and cancer associated thrombosis. The affordability and access to these drugs may pose an issue for many patients under healthcare systems not providing for these medications. With four new anticoagulants coming onboard very quickly, the focus has shifted to the practical approach and management in real life as many clinicians are not yet familiar with the DOACs. Clinicians need to be educated on how to manage this new class for drugs, from choosing the appropriate drug to prevention and managing bleeding complications as a lack of knowledge and understanding in these drugs will lead to inappropriate use and compromise on patient safety.