Facing real-life with direct oral anticoagulants in patients with nonvalvular atrial fibrillation: outcomes from the first observational and prospective study in a Spanish population

[Current situation of direct oral anticoagulants in primary care in Spain: Positioning of SEMERGEN in 2023]

Oral anticoagulation is the key to reduce the risk of stroke in atrial fibrillation. Although vitaminK antagonists (VKA) have classically been used for this purpose, they have been largely overcome by direct oral anticoagulants (DOAC), as demonstrated by evidence from clinical trials, real-life and population studies. In fact, all clinical practice guidelines recommend their use preferentially over VKA. However, in Spain the prescription of DOAC is subordinated to an inspection visa that includes the clinical conditions defined in the Therapeutic Positioning Report of the Spanish Medicines Agency, and that still imposes important restrictions on their use, limiting the benefits of using DOACs in patients with atrial fibrillation (AF), and also generating inequalities between the different autonomous communities. In fact, the use of DOAC in Spain is much lower than that observed in neighboring countries. This has made that while in other countries the incidence of ischemic stroke has decreased at the population level, along with a reduction in the cost per patient with AF, in Spain this decrease has been modest. For all these reasons, and for assuring the sustainability of the health care system, we ask for the elimination of the visa so that DOAC can be prescribed according to the recommendations made by the guidelines. In addition, we are also committed to reinforce medical education and decisions made by consensus with the patient, with the primary care physician acquiring a key role in the protection of the patient with AF.

Comparison of vitamin K and non-vitamin K oral anticoagulants and the bleeding frequency in the emergency department

INTRODUCTION

Safety studies of anticoagulant therapy have so far been conducted on many subjects in controlled conditions (i.e., clinically monitored) and demonstrated the noninferiority of new ones over old anticoagulant drugs. Data on the propositions for the presence of symptoms and signs of bleeding among various anticoagulants in the emergency department indicate that these data do not match the data published so far.

AIM

The aim of the study was to investigate the differences in the frequency of bleeding and bleeding-related symptoms as a reason for emergency department attendance in patients on anticoagulant therapy.

METHODS

The study included patients from the emergency department of University Hospital for one year, who were on anticoagulant therapy and who met the inclusion criteria. Out of a total of 595 patients, 409 were on warfarin (68.74%), and the rest were taking direct oral anticoagulants (DOAC): dabigatran 71 (11.93%), rivaroxaban 66 (11.09%) and apixaban 49 (8.23%).

RESULTS

Out of 409 patients taking warfarin, 34.4% were adequately anticoagulated with the frequency of bleeding 13.7%, while in 57.2% of patients, PT INR was higher than the reference values with the frequency of bleeding 15.0%. A comparison between all DOAC groups and adequately anticoagulated warfarin patients in the frequency of bleeding and bleeding-related symptoms as a reason for emergency attendance yielded a difference that was marginally statistically significant (Pearson Chi-Square = 7.554, p = 0.052).

CONCLUSION

Monitoring the frequency of bleeding and bleeding-related symptoms in patients on oral anticoagulant therapy as a reason for emergency department attendance may be a new safety and efficacy factor in real-life patient scenarios.

Effect of edoxaban compared with other oral anticoagulants for stroke prevention in patients with atrial fibrillation: A meta-analysis

Background and aim

Current observational studies have compared the effectiveness and safety of edoxaban with other oral anticoagulants in patients with AF, but the results are still disputed. This meta-analysis was conducted to compare the effect of edoxaban in patients with AF.

Methods

We performed systematic research from the PubMed, EMBASE, and Cochrane Library databases until November 2022 to obtain relevant observational studies. Adjusted risk ratios (RRs) and 95 % confidence intervals (CIs) of the outcomes were collected and pooled by a random-effects model. This study was prospectively registered in PROSPERO (CRD42022314222).

Results

A total of 17 observational studies were included in this meta-analysis. Compared with vitamin K antagonists, edoxaban was associated with lower risks of stroke or systemic embolism (RR = 0.67, 95 % CI:0.61-0.74), major bleeding (RR = 0.54, 95 % CI:0.44-0.67), and intracranial hemorrhage (RR = 0.51, 95 % CI:0.29-0.90). Compared with dabigatran or rivaroxaban, edoxaban was associated with reduced risks of stroke or systemic embolism (dabigatran [RR = 0.76, 95 % CI:0.66-0.87]; rivaroxaban [RR = 0.81, 95 % CI:0.70-0.94]) and major bleeding (dabigatran [RR = 0.82, 95 % CI:0.69-0.98]; rivaroxaban [RR = 0.81, 95 % CI:0.70-0.94]). Compared with apixaban, edoxaban was associated with a reduced risk of stroke or systemic embolism (RR = 0.87, 95 % CI:0.79-0.97), but had similar risks of bleeding events.

Conclusions

Our current evidence suggested that edoxaban might have superior effectiveness and/or safety outcomes than vitamin K antagonists, dabigatran, rivaroxaban, and apixaban for stroke prevention in patients with AF.

Patterns and outcomes of switching direct oral anticoagulants in non-valvular atrial fibrillation: a real-world experience from Spain

AIMS

The aim is to evaluate a management program for direct oral anticoagulants (DOACs) in non-valvular atrial fibrillation (NVAF) patients according to their profiles, appropriateness of dosing, patterns of crossover, effectiveness and safety. This is an observational and longitudinal prospective study in a cohort of patients attended in daily clinical practice in a regional hospital in Spain with 3-year a follow-up plan for patients initiating dabigatran, rivaroxaban or apixaban between JAN/2012-DEC/2016.

METHODS

We analyzed 490 episodes of treatment (apixaban 2.5 9.4%, apixaban 5 21.4%, dabigatran 75 0.6%, dabigatran 110 12,4%, dabigatran 150 19.8%, rivaroxaban 15 17.8% and rivaroxaban 20 18.6%) in 445 patients. 13.6% of patients on dabigatran, 9.7% on rivaroxaban, and 3.9% on apixabanswitched to other DOACs or changed dosing.

RESULTS

Apixaban was the most frequent DOAC switched to. The most frequent reasons for switching were toxicity (23.8%), bleeding (21.4%) and renal deterioration (16.7%). Inappropriateness of dose was found in 23.8% of episodes. Rates of stroke/transient ischemic attack (TIA) were 1.64/0.54 events/100 patients-years, while rates of major, clinically relevant non-major (CRNM) bleeding and intracranial bleeding were 2.4, 5, and 0.5 events/100 patients-years. Gastrointestinal and genitourinary bleeding were the most common type of bleeding events (BE). On multivariable analysis, prior stroke and age were independent predictors of stroke/TIA. Concurrent platelet inhibitors, male gender and age were independent predictors of BE.

CONCLUSION

This study complements the scant data available on the use of DOACs in NVAF patients in Spain, confirming a good safety and effectiveness profile.

Comparative Effectiveness and Safety Between Apixaban, Dabigatran, Edoxaban, and Rivaroxaban Among Patients With Atrial Fibrillation : A Multinational Population-Based Cohort Study

BACKGROUND

Current guidelines recommend using direct oral anticoagulants (DOACs) over warfarin in patients with atrial fibrillation (AF), but head-to-head trial data do not exist to guide the choice of DOAC.

OBJECTIVE

To do a large-scale comparison between all DOACs (apixaban, dabigatran, edoxaban, and rivaroxaban) in routine clinical practice.

DESIGN

Multinational population-based cohort study.

SETTING

Five standardized electronic health care databases, which covered 221 million people in France, Germany, the United Kingdom, and the United States.

PARTICIPANTS

Patients who were newly diagnosed with AF from 2010 through 2019 and received a new DOAC prescription.

MEASUREMENTS

Database-specific hazard ratios (HRs) of ischemic stroke or systemic embolism, intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model.

RESULTS

A total of 527 226 new DOAC users met the inclusion criteria (apixaban, n = 281 320; dabigatran, n = 61 008; edoxaban, n = 12 722; and rivaroxaban, n = 172 176). Apixaban use was associated with lower risk for GIB than use of dabigatran (HR, 0.81 [95% CI, 0.70 to 0.94]), edoxaban (HR, 0.77 [CI, 0.66 to 0.91]), or rivaroxaban (HR, 0.72 [CI, 0.66 to 0.79]). No substantial differences were observed for other outcomes or DOAC-DOAC comparisons. The results were consistent for patients aged 80 years or older. Consistent associations between lower GIB risk and apixaban versus rivaroxaban were observed among patients receiving the standard dose (HR, 0.72 [CI, 0.64 to 0.82]), those receiving a reduced dose (HR, 0.68 [CI, 0.61 to 0.77]), and those with chronic kidney disease (HR, 0.68 [CI, 0.59 to 0.77]).

LIMITATION

Residual confounding is possible.

CONCLUSION

Among patients with AF, apixaban use was associated with lower risk for GIB and similar rates of ischemic stroke or systemic embolism, ICH, and all-cause mortality compared with dabigatran, edoxaban, and rivaroxaban. This finding was consistent for patients aged 80 years or older and those with chronic kidney disease, who are often underrepresented in clinical trials.

PRIMARY FUNDING SOURCE

None.

Rivaroxaban for the prevention of outcomes in patients with atrial fibrillation in clinical practice: an indirect comparison of national and international registries

Objective: To analyze the effectiveness and safety of rivaroxaban in patients with atrial fibrillation (AF). Methods: The clinical profile and outcomes of the EMIR study were indirectly compared with those of ROCKET-AF, eight other Spanish observational studies and XANTUS. Results: In EMIR, mean age was 74.2 years and CHA₂DS₂-VASc was 3.5. In the rivaroxaban arm of the ROCKET-AF trial, mean age was 73 years and CHADS₂ was 3.5, whereas in the Spanish studies mean age ranged from 74.9 years to 78.4 years and CHA₂DS₂-VASc from 3.5 to 4.3. In EMIR, rates of stroke/systemic embolism, major adverse cardiovascular events, cardiovascular death and major bleeding were 0.57, 1.07, 0.63 and 1.04 events/100 patient-years, respectively. In ROCKET-AF, these numbers were 1.7, 3.91, 1.53 and 3.6 events/100 patient-years, respectively. In the Spanish studies, rates of stroke and major bleeding were 0-1.8 and 0.22-4.2 events/100 patient-years, respectively. In XANTUS, rates of stroke, major adverse cardiovascular events and major bleeding were 0.7, 1.8 and 2.1 events/100 patient-years, respectively. Conclusion: Despite the fact that rivaroxaban is prescribed for elderly patients with a high thromboembolic risk, rates of outcomes remain low.

Antithrombotic Therapy in Elderly Patients with Acute Coronary Syndromes

The treatment of acute coronary syndrome (ACS) in elderly patients continues to be a challenge because of the characteS.G.B.ristics of this population and the lack of data and specific recommendations. This review summarizes the current evidence about critical points of oral antithrombotic therapy in elderly patients. To this end, we discuss the peculiarities and differences reported referring to dual antiplatelet therapy (DAPT) in ACS management in elderly patients and what might be the best option considering these population characteristics. Furthermore, we analyze antithrombotic strategies in patients with atrial fibrillation (AF), with a particular focus on those cases that also present coronary artery disease (CAD). It is imperative to deepen our knowledge regarding the management of these challenging patients through real-world data and specifically designed geriatric studies to help resolve the questions remaining in their disease management.

Changing paradigms: from prevention of thromboembolic events to improved survival in patients with atrial fibrillation

Atrial fibrillation is associated with a five-fold increase in the risk of stroke. Current guidelines recommend the use of the CHA2DS2-VASc score to stratify the risk of stroke. In addition, guidelines recommend the identification of the conditions that increase the risk of haemorrhage to be modified and thus decrease the risk of bleeding. Nevertheless, many patients with a high thromboembolic risk are prescribed antiplatelet treatment or do not receive any antithrombotic therapy. In addition, therapeutic inertia is common in anticoagulated patients taking vitamin K antagonists, and underdosing is an emerging problem with direct oral anticoagulants, probably because many physicians consider the risk of stroke and the risk of major bleeding to be equal. It is necessary to develop a new approach to risk stratification, an approach that moves from morbidity to mortality, i.e., from stratification of the risk of stroke and major bleeding to stratification of the risk of mortality associated with stroke and the risk of mortality associated with bleeding. In this article, we propose a novel risk stratification approach based on the mortality associated with stroke and bleeding, illustrated by data derived from the literature.

Thromboembolic and bleeding events with rivaroxaban in clinical practice in Spain: impact of inappropriate doses (the EMIR study)

Aim: To analyze the frequency and variables related to inappropriate rivaroxaban dosage in clinical practice and its impact on outcomes after 2 years. Materials & methods: Postauthorization, observational, multicenter study, in which atrial fibrillation patients, treated with rivaroxaban ≥6 months were included. Results: A total of 1421 patients (74.2 ± 9.7 years, CHA₂DS₂-VASc 3.5 ± 1.6) were included. Overall, 22.9% received rivaroxaban 15 mg. The proper dose of rivaroxaban was taken by 83.3% (9.7% underdosed, 7.0% overdosed). Older age and renal insufficiency were associated with inadequate rivaroxaban dosage. There was a trend toward higher all-cause mortality among underdosed patients (adjusted hazard ratio 1.39; 95% CI 0.75-2.58), and more bleedings in overdosed patients (2.29 vs 0.80 events/100 patient-years; p = 0.14). Conclusion: In clinical practice, rivaroxaban is properly dosed in most patients.

Impact of anticoagulant exposure misclassification on the bleeding risk of direct oral anticoagulants

Aims

Drug exposure status based on routinely collected data might be misclassified when the database contains only prescriptions from 1 type of prescriber (e.g. general practitioner and not specialist). This study aims to quantify the impact of such exposure misclassification on the risk of major bleeding and stroke/transient ischaemic attack (TIA)associated with direct oral anticoagulants (DOACs) vs. vitamin K antagonists (VKAs).

Methods

Incident anticoagulant users (>12 mo free of anticoagulation use) in the Dutch PHARMO Database Network between 2008 and 2017 were included. Drug exposure was assessed using pharmacy dispensing information. The risks of hospital admission of major bleeding for DOAC vs. VKA users was assessed with Cox regression analysis, where exposure was based on all dispensings, on general practitioner (GP)‐prescribed dispensings only or on specialist‐prescribed dispensings only. Hazard ratios (HRs) were estimated also for hospitalization for gastrointestinal bleeding, intracranial bleeding and stroke/TIA.

Results

We included 99 182 VKA‐initiators and 21 795 DOAC‐initiators. Use of DOAC was associated with a lower risk of major bleeding compared to VKA use; HR 0.79 (95% confidence interval 0.70–0.90), 0.78 (0.68–0.91) and 0.62 (0.50–0.76), for exposure based on complete dispensing information, only GP‐ and only specialist‐prescribed dispensings, respectively. Similar results were found for the other bleeding outcomes. For stroke/TIA the HRs were 0.96 (0.84–1.09), 1.00 (0.84–1.18) and 0.72 (0.58–0.90), respectively.

Conclusion

Including only GP‐prescribed anticoagulant dispensings in this case did not materially impact the effect estimates compared to including all anticoagulant dispensings. Including only specialist‐prescribed dispensings, however, strengthened the effect estimates.

Critical appraisal and issues regarding generalisability of comparative effectiveness studies of NOACs in atrial fibrillation and their relation to clinical trial data: a systematic review

OBJECTIVE

To critically appraise the published comparative effectiveness studies on non-vitamin K antagonist oral anticoagulants (NOACs) in non-valvular atrial fibrillation (NVAF). Results were compared with expectations formulated on the basis of trial results with specific attention to the patient years in each study.

METHODS

All studies that compared the effectiveness or safety between at least two NOACs in patients with NVAF were eligible. We performed a systematic literature review in Medline and EMbase to investigate the way comparisons between NOACs were made, search date 23 April 2019. Critical appraisal of the studies was done using among others ISPOR Good Research Practices for comparative effectiveness research.

RESULTS

We included 39 studies in which direct comparison between at least two NOACs were made. Almost all studies concerned patient registries, pharmacy or prescription databases and/or health insurance database studies using a cohort design. Corrections for differences in patient characteristics was applied in all but two studies. Eighteen studies matched using propensity scores (PS), 8 studies weighted patients based on the inverse probability of treatment, 1 study used PS stratification and 10 studies applied a proportional hazards model. These studies have some important limitations regarding unmeasured confounders and channelling bias, even though the larger part of the studies were well conducted technically. On the basis of trial results, expected differences are small and a naïve analysis suggests trials with between 7200 and 56 500 patients are needed to confirm the observed differences in bleedings and between 51 800 and 7 994 300 to confirm differences in efficacy.

DISCUSSION

Comparisons regarding effectiveness and safety between NOACs on the basis of observational data, even after correction for baseline characteristics, may not be reliable due to unmeasured confounders, channelling bias and insufficient sample size. These limitations should be kept in mind when results of these studies are used to decide on ranking NOAC treatment options.

Prevención del ictus en pacientes con fibrilación auricular. Mejorar la protección enla era de la COVID-19

La fibrilación auricular aumenta hasta en 5 veces el riesgo de ictus. Los ictus cardioembólicos habitualmente son más graves y tienen altas tasas de recurrencias y discapacidad permanente en comparación con los ictus de otras etiologías. En consecuencia, la reducción del riesgo de ictus mediante una adecuada anticoagulación es uno de los principales objetivos en el tratamiento de los pacientes con fibrilación auricular. Los antagonistas de la vitamina K han sido ampliamente superados por los anticoagulantes orales de acción directa, ya que tanto los resultados de los ensayos clínicos como los de los estudios de práctica clínica y, últimamente, estudios poblacionales han demostrado que los anticoagulantes orales de acción directa tienen mayores eficacia (menos ictus y muerte) y seguridad (menos hemorragias intracraneales) que los antagonistas de la vitamina K. Además, durante la pandemia de COVID-19, el empleo preferente de anticoagulantes orales de acción directa frente a los antagonistas de la vitamina K constituye una estrategia clave para garantizar una calidad óptima de la anticoagulación y una mejor protección del paciente contra el SARS-CoV-2, al no precisarse control de la razón internacional normalizada.

The problem of underdosing with direct-acting oral anticoagulants in elderly patients with nonvalvular atrial fibrillation

Unless contraindicated, anticoagulant therapy should be prescribed to elderly patients with atrial fibrillation. Direct-acting oral anticoagulants (DOACs) are superior to vitamin K antagonists for preventing stroke. This, together with their higher net clinical benefit, makes DOACs the treatment of choice in this population. However, due to the concerns about bleeding and the need for dose adjustment based on clinical variables, underdosing of DOACs is common and the risk of stroke high. Drugs with more easily adjusted doses are likely associated with a lower risk of dosing errors and, therefore, a greater protective effect. Correct dosing can ensure a maximal net benefit of DOACs in elderly patients with atrial fibrillation.

Real-life behaviour of direct oral anticoagulants in a Spanish cohort with non-valvular atrial fibrillation: Refase Registry

Aim: To analyse the effectiveness and safety of DOAC (direct oral anticoagulants) in non-valvular atrial fibrillation (NVAF) patients attending clinical practice.Methods: Retrospective study of AF patients who started treatment with DOAC from January 1, 2013 to December 31, 2016 in three Spanish hospitals. Mean follow-up was 1.6 years. The primary outcomes were rates of all-cause death, ischaemic stroke, and bleeding. These outcomes were also studied depending on correct dosage adjustment and standard/adjusted dose.Results: The study included 2494 patients (age = 76.0 ± 9.5 years, CHA₂DS₂-VASc = 4.0 ± 1.6). The most prescribed DOAC was rivaroxaban (41.1%). Patients taking dabigatran were the youngest (mean age = 73.1 ± 10.3 years), with better kidney function (mean CrCl = 80.6 ± 35.8 ml/min) and lower CHA₂DS₂-VASc (3.7 ± 1.4) and HAS-BLED (2.1 ± 0.9) scores. Patients taking apixaban were the oldest, and had the highest CHA2DS2-VASc and HAS-BLED scores (4.3 ± 1.6 and 2.6 ± 0.9, respectively). Rates of stroke/major bleeding/intracranial bleeding were 1.8/3.0/0.3 events per 100 patient-years, respectively, with no differences among DOAC. Based on dose adjustment according to technical data, it was observed that 517 patients (23.5%) received DOAC doses inconsistent with labelling (p < .001) and, within this group, under-dosed patients had a higher death rate although it did not reach a significant result after multivariate adjustment.Conclusions: The results of safety and efficacy are very similar to those of other previously published national registries. There were no differences among the different types of DOAC regarding outcomes. However, it was found that people taking the adjusted dose of the drug seemed to have a higher risk of death. A non-negligible proportion of patients received DOAC doses inconsistent with labelling (mostly underdose).