Discontinuation of oral anticoagulation in atrial fibrillation and risk of ischaemic stroke

Recurrent Ischemic Stroke in Patients With Atrial Fibrillation While Receiving Oral Anticoagulants

Importance

Patients with atrial fibrillation (AF) can have an ischemic stroke (IS) despite oral anticoagulant (OAC) treatment. Knowledge regarding the association between OAC discontinuation and the subsequent risk of recurrent IS in patients with AF is limited.

Objectives

To determine the risk of recurrent IS in patients with AF receiving OAC and to evaluate the association between OAC discontinuation and the risk of recurrent IS.

Design, Setting, and Participants

This is a nationwide cohort study of patients aged 50 years or older in Denmark who had AF and an IS (entry IS) and were initiating or restarting subsequent OAC treatment after being discharged between January 2014 and December 2021. Patients were followed up for recurrent IS until June 2022. Within this study cohort, a nested case-control analysis was performed in which patients with recurrent IS were matched to patients receiving OAC who had not yet experienced a stroke. Data were analyzed from May 25, 2023, to April 18, 2024.

Exposure

Use of OAC at the time of recurrent IS or the equivalent date in matched controls based on redeemed prescriptions.

Main Outcomes and Measures

The primary outcome was recurrent IS. Crude and adjusted cumulative incidences of recurrent IS and all-cause mortality were calculated in cohort analyses, and adjusted odds ratios (aORs) were determined for recurrent IS associated with OAC discontinuation in nested case-control analyses.

Results

The study cohort included 8119 patients (4392 [54.1%] male; mean [SD] age, 78.4 [9.6] years; median (IQR) CHA2DS2-VASc score, 4.0 [3.0-5.0]). Over a mean (SD) follow-up of 2.9 (2.2) years, 663 patients had a recurrent IS, of whom 533 (80.4%) were receiving OAC at the time of their recurrent IS. The crude cumulative incidence of recurrent IS at 1 year was 4.3% (95% CI, 5.9%-7.1%), and the crude cumulative incidence of all-cause mortality was 15.4% (95% CI, 14.7%-16.2%). Adjusted analysis showed similar results. Patients who discontinued OACs had a higher risk of recurrent IS (89 cases [13.4%], 180 controls [6.8%]; aOR, 2.13; 95% CI, 1.57-2.89) compared with patients still receiving OAC.

Conclusions and Relevance

The risks of recurrent IS and mortality were high in patients with AF despite secondary prevention with OAC, and OAC discontinuation doubled the risk of recurrent IS compared with patients who continued OAC. This finding highlights the importance of OAC continuation and the need for improved secondary stroke prevention in patients with AF.

Evaluating the effect of inequalities in oral anti-coagulant prescribing on outcomes in people with atrial fibrillation

Aims

Whilst anti-coagulation is typically recommended for thromboprophylaxis in atrial fibrillation (AF), it is often never prescribed or prematurely discontinued. The aim of this study was to evaluate the effect of inequalities in anti-coagulant prescribing by assessing stroke/systemic embolism (SSE) and bleeding risk in people with AF who continue anti-coagulation compared with those who stop transiently, permanently, or never start.

Methods and results

This retrospective cohort study utilized linked Scottish healthcare data to identify adults diagnosed with AF between January 2010 and April 2016, with a CHA2DS2-VASC score of ≥2. They were sub-categorized based on anti-coagulant exposure: never started, continuous, discontinuous, and cessation. Inverse probability of treatment weighting-adjusted Cox regression and competing risk regression was utilized to compare SSE and bleeding risks between cohorts during 5-year follow-up. Of an overall cohort of 47 427 people, 26 277 (55.41%) were never anti-coagulated, 7934 (16.72%) received continuous anti-coagulation, 9107 (19.2%) temporarily discontinued, and 4109 (8.66%) permanently discontinued. Lower socio-economic status, elevated frailty score, and age ≥ 75 were associated with a reduced likelihood of initiation and continuation of anti-coagulation. Stroke/systemic embolism risk was significantly greater in those with discontinuous anti-coagulation, compared with continuous [subhazard ratio (SHR): 2.65; 2.39-2.94]. In the context of a major bleeding event, there was no significant difference in bleeding risk between the cessation and continuous cohorts (SHR 0.94; 0.42-2.14).

Conclusion

Our data suggest significant inequalities in anti-coagulation prescribing, with substantial opportunity to improve initiation and continuation. Decision-making should be patient-centred and must recognize that discontinuation or cessation is associated with considerable thromboembolic risk not offset by mitigated bleeding risk.

Discontinuation of Oral Anticoagulants in Atrial Fibrillation Patients: Impact of Treatment Strategy and on Patients' Health Status

AIMS

The discontinuation of oral anticoagulants (OACs) remains as a significant concern in the management of atrial fibrillation (AF). The discontinuation rate may vary depending on management strategy, and physicians may also discontinue OACs due to concerns about patient satisfaction with their care. We aimed to assess the incidence of OAC discontinuation and its relationship to patients' health in an outpatient AF registry.

METHODS AND RESULTS

From a multicenter registry for newly recognized AF patients (n = 3313), we extracted 1647 (49.7%) patients with OACs and a CHA2DS2-Vasc score of ≥2. Discontinuation was defined as sustained cessation of OACs within a 1-year follow-up. We examined predictors associated with discontinuation and its relations to health status defined by the AFEQT questionnaire. Of the 1647 patients, 385 (23.6%) discontinued OACs after 1 year, with discontinuation rates varying across treatment strategies (15.3% for catheter ablation, 4.9% for rhythm control with antiarrhythmic drugs, and 3.0% for rate control). Successful rhythm control was associated with discontinuation in the catheter ablation (OR 6.61, 95% CI 3.00-14.6, p < 0.001) and antiarrhythmic drugs (OR 6.47, 95% CI 2.62-15.9, p < 0.001) groups, whereas the incidence of bleeding events within 1 year was associated with discontinuation in the rate control group. One-year AFEQT scores did not significantly differ between patients who discontinued OACs and those who did not in each treatment strategy group.

CONCLUSIONS

OAC discontinuation was common among AF patients with significant stroke risk but varied depending on the chosen treatment strategy. This study also found no significant association between OAC discontinuation and patients' health status.

Non‑persistence to Oral Anticoagulation Therapy in Elderly Patients with Non‑valvular Atrial Fibrillation

PURPOSE

To investigate the reasons for elderly atrial fibrillation (AF) patients not continuing their oral anticoagulation (OAC) treatment and the factors that influence this behavior.

METHODS

Elderly AF patients (aged≥75 years) hospitalized from December 2019 to May 2022 were consecutively enrolled. Clinical, demographic, and concomitant medication data were collected. The endpoint was defined as OAC discontinuation for more than 30 days or a switch to an alternative therapy. Predictors of OAC non-persistence were investigated using a multivariable Cox regression model.

RESULTS

This study included 560 participants (51.1% men, mean age 80.9±0.2 years). During a median follow-up of 20 months, medication persistence was observed in 322 patients (57.5%). Non-persistence was found to be significantly higher with warfarin than with NOAC (48.8% vs 33.6%, p = 0.006). In the multivariate analysis, OAC non-persistence was independently predicted by a history of permanent pacemaker implantation, the use of antiplatelet drugs, employee Medicare, living with children, college degree or above, and persistent AF (HR = 1.580, 1.586, 0.604, 0.668, 0.028, 0.769, p < 0.05, respectively). Treatment discontinuation within 3 months of discharge was observed in a large number of patients (81.8%). Medication discontinuation due to bleeding was more frequently observed in patients who continued for longer than 3 months (p < 0.001), while discontinuation due to patient preference was more frequent in those with shorter durations (≤3 months) (p = 0.049). Patient preference was the second leading cause of non-persistence in patients, regardless of whether they were taking warfarin or NOAC.

CONCLUSION

OAC non-persistence remains high among elderly AF patients during long-term follow-up, with a significant proportion discontinuing shortly after discharge. This pattern of non-persistence is heavily influenced by demographic factors and patient preference. Further interventions should be developed based on the reasons and risk factors to improve persistence and initiated early in the treatment process.

[What is confirmed in the treatment of ischemic stroke]

Ischemic stroke is one of the leading causes of death worldwide and the most frequent cause of permanent disability in adulthood. The acute treatment of stroke is time-critical and, according to the time is brain principle, it is important to determine as soon as possible whether recanalization treatment that can save the penumbra is possible. Intravenous thrombolysis (IVT) and, if a large vessel occlusion is identified, endovascular treatment (EVT) possibly in combination with IVT, are recommended. Further treatment in a stroke unit is another important component of acute stroke treatment. The best secondary preventive treatment must already be initiated in the acute phase. The cause of stroke guides making decisions on the ideal secondary preventive strategy. The most important etiologies of stroke are cardiac embolism, atherosclerotic macroangiopathy and cerebral microangiopathy (small vessel disease). Less frequent causes are dissections of arteries supplying the brain or vasculitis. In up to 20-30% of all cases, however, no clear etiology can be determined despite intensive investigation of the cause. This means corresponding uncertainty in the optimal secondary prevention that consists in particular of an anticoagulant medication adapted to the etiology, treatment of cardiovascular risk factors and if necessary surgical or interventional desobliterative procedures. This article describes the diagnostic procedure and the evidence-based treatment of ischemic stroke.

Effect of clinic-based single-lead electrocardiogram rhythm assessment on oral anticoagulation prescriptions in patients with previously diagnosed atrial fibrillation

Background

Despite benefits of oral anticoagulation (OAC), many individuals with diagnosed atrial fibrillation (AF) do not receive OAC.

Objective

The purpose of this study was to assess whether cardiac rhythm assessment for AF impacted use of OAC in patients with previously diagnosed AF.

Methods

VITAL-AF was a cluster randomized controlled trial conducted in 16 primary care practices assessing the efficacy of AF rhythm assessment with single-lead electrocardiogram in routine care. Patients 65 years and older were offered rhythm assessment at visits. In this secondary analysis, we evaluated rhythm assessment uptake and compared initiation and discontinuation of OAC in patients with previously diagnosed AF from intervention and control arms over 1 year.

Results

The study included 4593 patients with previously diagnosed AF (2250 intervention; 2343 control). In the intervention arm, 2022 (89.9%) completed rhythm assessment (median 2 visits with rhythm assessment) and 40.1% had ≥1 "Possible AF" result. Initiation of OAC was similar in the intervention (17.7%) and control (19.1%) arms but was influenced by the rhythm assessment result: higher with a "Possible AF" (26.1%; adjusted odds ratio [aOR] 1.62; 95% confidence interval [CI] 1.04-2.51), and lower with a "Normal" result (9.9%; aOR 0.45; 95% CI 0.29-0.71) compared to control. OAC discontinuation was similar in the intervention (6.3%) and control (7.2%) arms, with lower discontinuation with a "Possible AF" result (3.8%; aOR 0.51; 95% CI 0.32-0.81).

Conclusions

Including patients with previously diagnosed AF in a point-of-care rhythm assessment strategy did not increase overall OAC use compared to the control arm. However, the rhythm assessment result influenced both initiation and discontinuation of OAC.

Payer formulary tier increases of apixaban: how patients respond and potential implications

OBJECTIVE

To assess potential impacts of formulary tier increases of apixaban-an efficacious oral anticoagulant (OAC) for preventing stroke in patients with atrial fibrillation (AF)-on patients' prescription drug plan (PDP) switching and OAC treatment patterns.

METHODS

Nationwide claims data for Medicare beneficiaries with Parts A, B, and D (100% sample) were used to assess apixaban-treated AF patients who faced a formulary tier increase for apixaban in 2017 by their Part D PDP. Patients' out-of-pocket (OOP) costs for apixaban were described, along with PDP switching and OAC treatment patterns.

RESULTS

Among 1845 included patients, 97.7% had apixaban on tier 3 of their plan's formulary in 2016 and faced its increase to tier 4 for 2017. Approximately 4% (N = 81) of patients pre-emptively switched to a different PDP for 2017 with almost all switching to plans with apixaban on a lower formulary tier and 85.2% continuing apixaban treatment. Among the 96% (N = 1764) of patients who remained on the same PDP for 2017, over half (57.5%) continued apixaban treatment, despite increased OOP costs ($54 vs. $135 for a 30-day supply in 2016 vs. 2017). Only 12.4% of those who remained on the same plan for 2017 switched to another OAC, while as much as 30.1% discontinued OACs. These discontinuers exhibited higher comorbidity burdens than patients continuing on any OAC.

CONCLUSION

The majority of patients continued on apixaban despite higher OOP cost, suggesting patients' reluctance to change treatment for non-medical reasons; however, 30% of patients discontinued OAC treatment after higher apixaban tier placement.

Clinical outcomes of oral anticoagulant discontinuation in atrial fibrillation: a systematic review and meta-analysis

INTRODUCTION

Oral anticoagulants (OACs) should generally be continued lifelong in patients with atrial fibrillation (AF) to ensure optimal benefits, unless contraindications arise. However, discontinuation of OACs might occur for various reasons, potentially affecting clinical outcomes. In this review, we synthesized evidence on the clinical outcomes following OAC discontinuation in patients with AF.

METHODS

We conducted a systematic review and meta-analysis using PubMed, Embase and Scopus. Cohort or case-control studies were included if data were available on clinical outcomes of OAC discontinuation, compared with continuation, in patients with AF. A random-effect meta-analyses were conducted for key outcomes of stroke, mortality, and major bleeding.

RESULTS

Eighteen observational studies having a total of 283,418 patients were included. Discontinuation significantly increased the risk of stroke (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.58-2.23), all-cause (HR 1.90; 95% CI 1.40-2.59) and cardiovascular (HR 1.83; 95% CI 1.06-3.18) mortality. The risk of major bleeding was not significantly different between the discontinued and continued groups (HR 1.04; 95% CI 0.72-1.52).

CONCLUSIONS

Discontinuation of OAC therapy was associated with an increased risk of stroke and mortality, with no difference in the risk of major bleeding. Acknowledging heterogeneity among the studies, the findings underline the need to ensure continuity of OAC therapy in patients with AF to prevent thrombotic complications and associated mortality.

PROSPERO REGISTRATION NUMBER

CRD42020186116.

Pre- and post-stroke oral antithrombotics and mortality in patients with ischaemic stroke

BACKGROUND

Reducing stroke occurrence requires the effective management of cardiovascular and other stroke risk factors.

PURPOSE

To describe pre- and post-stroke medication use, focusing on antithrombotic therapy and mortality risk, in individuals hospitalised for ischaemic stroke (IS) in the United Kingdom.

METHOD

Using primary care electronic health records from the United Kingdom, we identified patients hospitalised for IS (July 2016-September 2019) and classed them into three groups: atrial fibrillation (AF) diagnosed pre-stroke, AF diagnosed post-stroke, and non-AF stroke (no AF diagnosed pre-/post-stroke). We determined use of cardiovascular medications in the 90 days pre- and post-stroke and calculated mortality rates.

RESULTS

There were 3201 hospitalised IS cases: 76.2% non-AF stroke, 15.7% AF pre-stroke, and 8.1% AF post-stroke. Oral anticoagulant (OAC) use increased between the pre- and post-stroke periods as follows: 54.3%-78.7% (AF pre-stroke group), 2.3%-84.8% (AF post-stroke group), and 3.4%-7.3% (non-AF stroke group). Corresponding increases in antiplatelet use were 30.8%-35.4% (AF pre-stroke group) 38.5%-47.5% (AF post-stroke group), and 37.5%-87.3% (non-AF stroke group). Among all IS cases, antihypertensive use increased from 66.8% pre-stroke to 78.8% post-stroke; statin use increased from 49.6%-85.2%. Mortality rates per 100 person-years (95% CI) were 17.30 (14.70-20.35) in the AF pre-stroke group and 9.65 (8.81-10.56) among all other stroke cases.

CONCLUSION

Our findings identify areas for improvement in clinical practice, including optimising the level of OAC prescribing to patients with known AF, which could potentially help reduce the future burden of stroke.

Stand-Alone Left Atrial appendage occlusion for throMboembolism prevention in nonvalvular Atrial fibrillatioN DiseasE Registry (SALAMANDER): protocol for a prospective observational nationwide study

INTRODUCTION

Atrial fibrillation (AF) is a prevalent disease considerably contributing to the worldwide cardiovascular burden. For patients at high thromboembolic risk (CHA₂DS₂-VASc ≥3) and not suitable for chronic oral anticoagulation, owing to history of major bleeding or other contraindications, left atrial appendage occlusion (LAAO) is indicated for stroke prevention, as it lowers patient's ischaemic burden without augmentation in their anticoagulation profile.

METHODS AND ANALYSIS

Stand-Alone Left Atrial appendage occlusion for throMboembolism prevention in nonvalvular Atrial fibrillatioN DiseasE Registry (SALAMANDER) will be conducted in 10 heart surgery and cardiology centres across Poland to assess the outcomes of LAAO performed by fully thoracoscopic-epicardial, percutaneous-endocardial or hybrid endo-epicardial approach. The registry will include patients with nonvalvular AF at a high risk of thromboembolic and bleeding complications (CHA2DS2-VASc Score ≥2 for males, ≥3 for females, HASBLED score ≥2) referred for LAAO. The first primary outcome is composite procedure-related complications, all-cause death or major bleeding at 12 months. The second primary outcome is a composite of ischaemic stroke or systemic embolism at 12 months. The third primary outcome is the device-specific success assessed by an independent core laboratory at 3-6 weeks. The quality of life (QoL) will be assessed as well based on the QoL EQ-5D-5L questionnaire. Medication and drug adherence will be assessed as well.

ETHICS AND DISSEMINATION

Before enrolment, a detailed explanation is provided by the investigator and patients are given time to make an informed decision. The patient's data will be protected according to the requirements of Polish law, General Data Protection Regulation (GDPR) and hospital Standard Operating Procedures. The study will be conducted in accordance with the Declaration of Helsinki. Ethical approval was granted by the local Bioethics Committee of the Upper-Silesian Medical Centre of the Silesian Medical University in Katowice (decision number KNW/0022/KB/284/19). The results will be published in peer-reviewed journals and presented during national and international conferences.

TRIAL REGISTRATION NUMBER

NCT05144958.

Epicardial adipose tissue, obesity and the occurrence of atrial fibrillation: an overview of pathophysiology and treatment methods

INTRODUCTION

Obesity is a chronic disease, which has significant health consequences and is a staggering burden to health care systems. Obesity can have harmful effects on the cardiovascular system, including heart failure, hypertension, coronary heart disease, and atrial fibrillation (AF). One of the possible substrates might be epicardial adipose tissue (EAT), which can be the link between AF and obesity. EAT is a fat deposit located between the myocardium and the visceral pericardium. Numerous studies have demonstrated that EAT plays a pivotal role in this relationship regarding atrial fibrillation.

AREAS COVERED

This review will focus on the role of obesity and the occurrence of atrial fibrillation (AF) and examine the connection between these and epicardial adipose tissue (EAT). The first part of this review will explain the pathophysiology of EAT and its association with the occurrence of AF. Secondly, we will review bariatric and metabolic surgery and its effects on EAT and AF.

EXPERT COMMENTARY

In this review, the epidemiology, pathophysiology, and treatments methods of AF are explained. Secondly the effects on EAT were elucidated. Due to the complex pathophysiological link between EAT, AF, and obesity, it is still uncertain which treatment strategy is superior.

Antithrombotic therapy and clinical outcomes at 1 year in the Spanish cohort of the EORP-AF Long-term General Registry

BACKGROUND

Atrial fibrillation (AF) increases the risk of thromboembolism. We investigate the efficacy and safety of oral anticoagulation (OAC) therapy and explored the number needed to treat for net effect (NNTnet) of OAC in the Spanish cohort of the EURObservational Research Programme-AF (EORP-AF) Long-term General Registry.

METHODS

The EORP-AF General Registry is a prospective, multicentre registry conducted in ESC countries, including consecutive AF patients. For the present analysis, we used the Spanish cohort, and the primary outcome was any thromboembolism (TE)/acute coronary syndrome (ACS)/cardiovascular death during the first year of follow-up.

RESULTS

729 AF patients were included (57.1% male, median age 75 [IQR 67-81] years, median CHA₂ DS₂ -VASc and HAS-BLED of 3 [IQR 2-5] and 2 [IQR 1-2], respectively). 548 (75.2%) patients received OAC alone (318 [43.6%] on VKAs and 230 [31.6%] on DOACs). After 1 year, the use of OAC alone showed lower rates of any TE/ACS/cardiovascular death (3.0%/year; p < 0.001) compared to other regimens, and non-use of OAC alone (HR 4.18, 95% CI 2.12-8.27) was independently associated with any TE/ACS/cardiovascular death. Balancing the effects of treatment, the NNTnet to provide an overall benefit of OAC therapy was 24. The proportion of patients on OAC increased at 1 year (87% to 88.1%), particularly on DOACs (33.6% to 39.9%) (p = 0.015), with low discontinuation rates.

CONCLUSIONS

In this contemporary cohort of AF patients, OAC therapy was associated with better clinical outcomes at 1 year and positive NNTnet. OAC use slightly increased during the follow-up, with low discontinuation rates and higher prescription of DOACs.

Time Trends and Treatment Pathways in Prescribing Individual Oral Anticoagulants in Patients with Nonvalvular Atrial Fibrillation: An Observational Study of More than Three Million Patients from Europe and the United States

BACKGROUND

Data directly comparing trends in the use of different oral anticoagulants (OACs) among patients with atrial fibrillation (AF) from different countries are limited. We addressed this using a large-scale network cohort study in the United States (US), Belgium, France, Germany, and the United Kingdom (UK).

METHODS

We used nine databases (claims or electronic health records) that had been converted into the Observational Medical Outcomes Partnership Common Data Model with analysis performed using open-source analytical tools. We identified adults with AF and a first OAC prescription, either vitamin K antagonist (VKA) or direct oral anticoagulant (DOAC), from 2010 to 2017. We described time trends in use, continuation, and switching.

RESULTS

In 2010, 87.5%-99.8% of patients started on a VKA. By 2017, the majority started on a DOAC: 87.0% (US), 88.3% (Belgium), 93.1% (France), 88.4% (Germany), and 86.1%-86.7% (UK). In the UK, DOACs became the most common starting OAC in 2015, 2-3 years later than elsewhere. Apixaban was the most common starting OAC by 2017, 50.2%-57.8% (US), 31.4% (Belgium), 45.9% (France), 39.5% (Germany), and 49.8%-50.5% (UK), followed by rivaroxaban, 24.8%-32.5% (US), 25.7% (Belgium), 38.4% (France), 24.9% (Germany), and 30.2%-31.2% (UK). Long-term treatment was less common in the US than in Europe, especially the UK. A minority of patients switched from their index OAC in the short and long term.

CONCLUSIONS

From 2010 to 2017, VKA use had significantly declined and DOAC use had significantly increased in the US and Europe. Apixaban was the most prescribed OAC in 2017, followed by rivaroxaban.

Estimated Thresholds of Minimum Necessary Adherence for Effective Treatment with Direct Oral Anticoagulants - A Retrospective Cohort Study in Health Insurance Claims Data

BACKGROUND

An essential contribution regarding the prevention of thromboembolic events in patients with (non-valvular) atrial fibrillation (AF) is good adherence to direct oral anticoagulants (DOACs). However, it is an open question what "good" adherence means for DOACs or below which threshold non-adherence is clinically relevant for AF patients. Ultimately, such a classification could prevent strokes and associated costs through adjusted treatment regimens or supportive measures.

METHODS

We selected 10,092 AF patients from health insurance claims data between 2014 and 2018 who were issued a majority (at least half of the number) of maximum approved strength prescriptions of one of the following DOACs, namely rivaroxaban, apixaban, or dabigatran. Due to the limited sample size, the prescriptions of dabigatran had to be finally excluded for the cut-off analysis. DOAC adherence was calculated as the proportion of days covered (PDC) by dividing the days of theoretical use (days covered) of the drug by the duration in days of the observation interval. PDC cut-off values were derived from stroke risk as a function of continuous PDC values in time-to-event analyses and corresponding dose-response models. The influence of adherence-promoting interventions (targeted and untargeted) on the occurrence of strokes and related costs was then projected, considering intervention costs per patient.

RESULTS

The population had a mean age of 74.5 years and 50% were female. The median PDC was 0.79 ± 0.28 with a median follow-up time of 1218 days, in which 2% of all DOAC patients had a stroke. The adherence cut-offs for good adherence were identified at 0.78 for rivaroxaban and 0.8 for apixaban. Targeted interventions appeared to be far more cost-effective than untargeted interventions.

CONCLUSION

Clear adherence cut-offs enable healthcare professionals to identify patients with clinically relevant non-adherence. Interventions based on these cut-offs appear to be a promising means to optimize DOAC treatment.