Impact of pre-admission treatment with non-vitamin K oral anticoagulants on stroke severity in patients with acute ischemic stroke

Acute Ischaemic Stroke in Patients Treated with Direct Oral Anticoagulants: Potential Causes, Clinical Characteristics, and Short-Term Outcomes

Introduction

Direct oral anticoagulants (DOAC) are the first-line treatment for primary and secondary acute ischaemic stroke (AIS) prevention in patients with nonvalvular atrial fibrillation (NVAF), but a significant percentage of patients develop AIS despite being treated with DOAC. As the number of DOAC-treated patients is growing, so is the number of patients with AIS on DOAC. The aim of the study was to assess the incidence of AIS with prestroke DOAC treatment among patients hospitalised in the University Hospital in Kraków, to analyse the clinical characteristics of AIS occurring in patients on DOAC, and to identify potential causes of treatment ineffectiveness in this group.

Materials and Methods

In the study, we included all patients hospitalised in the Department of Neurology of the University Hospital in Kraków within one year (July 2022 to June 2023) with the diagnosis of AIS. The group was divided into two subgroups of patients with and without prestroke DOAC treatment. Based on medical files, we retrospectively analysed the profile of cardiovascular risk factors, stroke severity (assessed with National Institutes of Health Stroke Scale, NIHSS), use of causative stroke treatment and short-term outcomes (defined as NIHSS score, modified Rankin scale (mRS) score at discharge, in-hospital mortality, and secondary intracerebral haemorrhage among patients treated with mechanical thrombectomy, MT). Within the DOAC-treated subgroup, we looked for potential causes of AIS occurring despite DOAC treatment (valvular AF, poor adherence to treatment, underdosing, other prothrombotic conditions, aetiology of stroke other than thromboembolic, and drug-drug interactions).

Results

In the study, we included 768 AIS patients. 109 (14.2%) had a history of prestroke DOAC treatment. A potential cause of DOAC treatment failure was identified in the majority of them (n = 63, 57.8%). Patients with prestroke DOAC treatment had worse functional condition before stroke and higher stroke severity on admission but similar short-term outcomes and similar short-term effects of treatment with MT. DOAC (+) and DOAC (-) patients had different profiles of cardiovascular risk factors and different factors associated with short-term outcome. Conclusions and Clinical Implications. A potential cause of AIS occurring in DOAC-treated patients can be identified in most cases and in many of them prevented.

Admission Severity of Atrial-Fibrillation-Related Acute Ischemic Stroke in Patients under Anticoagulation Treatment: A Systematic Review and Meta-Analysis

Background: In non-valvular-associated atrial fibrillation (AF), direct oral anticoagulants (DOAC) are as effective as vitamin K antagonists (VKA) for the prevention of acute ischemic stroke (AIS). DOAC are associated with decreased risk and severity of intracranial hemorrhage. It is unknown if different pre-admission anticoagulants impact the prognosis of AF related AIS (AF-AIS). We sought to analyze the literature to assess the association between pre-admission anticoagulation (VKA or DOAC) and admission severity of AF-AIS. Methods: A Systematic literature search (PubMed and ScienceDirect) between January 2011 to April 2021 was undertaken to identify studies describing the outcome of AF-AIS. Results: A total of 128 articles were identified. Of 9493 patients, 1767 were on DOAC, 919 were on therapeutical VKA, 792 were on non-therapeutical VKA and 6015 were not anticoagulated. In comparison to patients without anticoagulation, patients with therapeutical VKA and under DOAC presented with less severe stroke (MD −1.69; 95% CI [−2.71, −0.66], p = 0.001 and MD −2.96; 95% Cl [−3.75, −2.18], p < 0.00001, respectively). Patients with non-therapeutical VKA presented with more severe stroke (MD 1.28; 95% Cl [0.45, 2.12], p = 0.003). Conclusions: In AF-AIS, patients under therapeutical VKA or DOAC have reduced stroke severity on admission in comparison to patients without any anticoagulation, with higher magnitude of protection for DOAC.

Time trends in stroke severity in the years 2005 to 2020: results from the Austrian Stroke Unit Registry

BACKGROUND AND PURPOSE

With aging population, there is an increase of atrial fibrillation (AF) and other vascular risk factors. We investigated trends in stroke severity at hospital admission with respect to AF and other risk factors in a prospective national stroke registry from 2005 to 2020.

METHODS

Data from the prospective Austrian Stroke Unit Registry were used to study demographic and clinical factors associated with the change in admission stroke severity over years. Time trends in admission stroke severity of patients with pre-stroke modified Rankin Score ≤ 3 were investigated with respect to clinical variables and predefined age groups 18-54, 55-64, 65-74, 75-84 and ≥ 85 years. Time trends were studied using robust generalized linear models assuming normal distribution with a log link. Stroke severity on admission was assessed according to the National Institutes of Health Stroke Scale Score (NIHSS).

RESULTS

In total, 140,312 patients with acute ischemic stroke were included in the analysis. Within the study period, mean patients' age increased from 70 to 72 years (p < 0.001) and median NIHSS at admission decreased from 4 to 3 (p < 0.001). The frequency of AF increased from 25 to 32% (p < 0.001). The decrease in median admission NIHSS was evident in all relevant subgroups but more pronounced in patients with risk factors including AF, diabetes, hypercholesterolemia, smoking, elderly patients and those with pre-stroke disability.

CONCLUSION

Despite an aging population and generally increasing AF frequency, we observed a consistent trend towards less disabling strokes on admission.

Association Between Oral Anticoagulants and Stroke Severity at Onset in Elderly Patients with Cardioembolic Stroke Due to Non-Valvular Atrial Fibrillation

OBJECTIVES

This study aimed to determine whether oral anticoagulant therapy affects the severity of cerebral infarction at onset in elderly patients with non-valvular atrial fibrillation.

MATERIALS AND METHODS

This retrospective study included 330 elderly patients (aged ≥75 years) who were hospitalized for cardioembolic stroke due to non-valvular atrial fibrillation. Patients' medical history, stroke severity at onset (National Institutes of Health Stroke Scale score), and the prevalence of large vessel occlusion were compared between patients who received oral anticoagulant therapy (n = 109) and those who did not receive oral anticoagulant therapy (n = 221).

RESULTS

Stroke severity was significantly lower in patients who received anticoagulants than in those who did not receive anticoagulants (6 versus 12; P = 0.021). Patients who did not receive anticoagulants had a significantly higher prevalence of large vessel occlusion (52% versus 37%; P = 0.010). After resampling based on propensity score matching, both median stroke severity (7 versus 12; P = 0.046) and large vessel occlusion prevalence (36% versus 57%; P = 0.019) were significantly lower in patients who received anticoagulant therapy.

CONCLUSIONS

The results of this study suggest that elderly patients with non-valvular atrial fibrillation who are administered oral anticoagulant therapy before the onset of cerebral infarction develop less severe stroke than those who are not receiving oral anticoagulant therapy. Thus, oral anticoagulant therapy should be actively considered in patients with non-valvular atrial fibrillation as it does not only prevents cerebral embolism, but also reduces the risk of severe sequelae.

Ischaemic stroke in anticoagulated patients with atrial fibrillation

Anticoagulation substantially reduces the risk of stroke in patients with atrial fibrillation (AF). However, recent studies have shown that up to 22%-36% of patients on anticoagulation will suffer an ischaemic stroke (IS). In this narrative review, we provide an overview of risk factors, mechanisms, management of acute IS and strategies for secondary prevention for patients with AF with stroke despite oral anticoagulation. For this paper, we reviewed available literature from important studies (randomised clinical trials, meta-analyses, reviews and case series) on patients with IS despite anticoagulation. We focused on recent studies that examined safety and efficacy of acute stroke treatments and evaluation and management strategies for secondary prevention. The literature review suggests that patients with AF with IS despite anticoagulation are a heterogeneous group with several possible mechanisms, which may include reduced or non-adherence to anticoagulation, competing non-cardioembolic stroke aetiologies or cardioembolic mechanisms separate from AF. The identification of one or more possible mechanisms of stroke despite anticoagulation may allow for a more targeted and individualised approach for secondary prevention. There are limited data to guide management in such patients, and strategies to prevent recurrent strokes include strict risk factor control and therapies targeting the most likely stroke mechanism. In cases where AF is suspected to be the culprit, clinical trials are needed to test the safety and efficacy of left atrial appendage occlusion plus anticoagulation versus continued anticoagulation alone.

Preceding direct oral anticoagulant administration reduces the severity of stroke in patients with atrial fibrillation - K-PLUS registry

BACKGROUND

Stroke severity can be mitigated by preceding anticoagulant administration in acute ischemic stroke patients with atrial fibrillation (AF). We investigated if such mitigative effects are different between warfarin and direct oral anticoagulants (DOACs).

MATERIAL AND METHODS

We collected data from a regional multicenter stroke registry. Ischemic stroke or transient ischemic attack patients with AF were included. Background characteristics, National Institutes of Health Stroke Scale (NIHSS) score on admission, lesion characteristics, and in-hospital death were analyzed according to preceding antithrombotic agents at onset.

RESULTS

A total of 2173 patients had AF; 628 were prescribed warfarin, 272 DOACs, 429 antiplatelets alone, and 844 no antithrombotics. The NIHSS score on admission was lowest in the DOACs group compared to the other groups. In neuroimaging analysis, small ischemic lesions were observed more frequently in the DOACs group, while large ischemic lesions were less frequent in this group. When the no antithrombotics group was used as a reference, the adjusted odds ratio for moderate to severe stroke was 0.56 (95% confidence interval, 0.40-0.78) in the DOACs group, while it was 0.98 (0.77-1.24) in the warfarin group and 0.94 (0.72-1.22) in the antiplatelets group. In-hospital mortality was lowest in the DOACs group compared to the other groups.

CONCLUSION

Preceding DOAC administration might mitigate the severity of stroke in AF patients more strongly than other antithrombotics, possibly leading to a better outcome in patients with stroke.

Use of NOACS in high-risk patients with atrial fibrillation in Saudi Arabia: Perspectives on improving patient care

BACKGROUND

Despite the widespread and increasing use of NOACs in Saudi Arabia, there is a lack of contemporary guidance specific to the region. In particular, guidance on NOAC use in high-risk patients who are more likely to experience bleeding with oral anticoagulant therapy is needed. There is an unmet need for a review of contemporary evidence coupled with expert insights on safe and effective NOAC use in high-risk patients with AF in Saudi Arabia.

RESEARCH DESIGN AND METHODS

This article provides a detailed review of contemporary literature on NOAC use in high-risk patients with AF. Additionally, key gaps in the literature are identified and expert insights are shared to guide effective management of patients and the significance of local data is evaluated with respect to challenges in optimizing the use of NOACs.

CONCLUSIONS

This article provides information that complements and expands on existing reviews and guidelines on NOAC use in patients with AF, with a focus on challenges specific to the Saudi Arabian context with the potential to make a positive contribution to the medical community in Saudi Arabia and in other nations.

Impact of direct oral anticoagulant off-label doses on clinical outcomes of atrial fibrillation patients: A systematic review

AIMS

Worldwide observational studies are evidencing discordance between guidelines and real-world practice regarding direct oral anticoagulant drug (DOAC) doses. This systematic review summarizes and evaluate DOACs use in real-world practice.

METHODS

This review was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines searching PubMed (MEDLINE) and Medscape databases.

RESULTS

Data from 75 studies showed that most of the patients treated with DOACs for stroke prevention in atrial fibrillation received doses in accordance to the guidelines. However, a significant number of patients received off-label doses (25-50% in most of the studies evaluated). DOAC overdosing was associated with increased all-cause mortality and worse bleeding events while underdosing was associated with increased cardiovascular hospitalization and, particularly for apixaban, with a nearly 5-fold increased risk of stroke.

CONCLUSION

Patients prescribed with off-label DOAC doses did not receive the full benefit of anticoagulation and presented an increased risk of stroke, bleeding and/or adverse effects.

Patients on NOACs in the Emergency Room

PURPOSE OF REVIEW

Despite the increasing use of NOACs, there is still uncertainty on how to treat NOAC patients presenting with neurological emergencies. Initial assessment of coagulation status is challenging but essential in these patients to provide best-possible treatment in case of ischemic or hemorrhagic stroke. Meanwhile, anticoagulation reversal strategies have been suggested; yet, the optimal management is still unestablished. The current review aims to provide up-to-date information on (i) how to identify patients with NOAC intake, (ii) which therapies are feasible in the setting of ischemic and hemorrhagic stroke as well as traumatic intracranial hemorrhage, and (iii) how to proceed with patients requiring emergency lumbar puncture.

RECENT FINDINGS

Despite several expert opinions, there is still an ongoing debate which NOAC patients presenting with ischemic stroke may benefit from recanalizing strategies and whether these treatment approaches can be performed safely. Results from two phase IV trials investigating the efficacy of NOAC-specific reversal agents in case of major bleeding seem promising with regard to hemostatic parameters, but these antidotes have not been verified to clinically benefit patients, and approval by authorities in parts is still pending. Specific reversal agents are on the way and will provide new treatment options in patients with NOAC-related ischemic and hemorrhagic stroke. Up to now, the decision which patients should undergo recanalizing treatment for ischemic stroke, or which specific pharmacological reversal treatment in hemorrhagic stroke should be initiated, has to be made cautiously on an individual basis after assessing hemostatic parameters.

Clinical presentation, diagnostic findings and management of cerebral ischemic events in patients on treatment with non-vitamin K antagonist oral anticoagulants - A systematic review

Background

Non-vitamin K antagonist oral anticoagulants (NOAC) are equally or potentially superior in terms of effectiveness in the prevention of ischemic stroke and carry a lower associated risk of intracranial hemorrhage compared to Vitamin K antagonists. Nevertheless, ischemic strokes also occur in patients who are being treated with NOAC. In those particular patients, knowledge about the underlying stroke etiology, clinical presentation, acute management, and complication rates is scarce.

Objective

Systematic literature review to provide a comprehensive clinical overview in terms of presentation, laboratory, imaging parameters and outcomes of patients suffering from acute cerebral ischemic events (i.e. TIA and acute ischemic stroke) while on treatment with a NOAC. Only if available, comparison to VKA is presented which was not the primary focus of this analysis.

Data sources

PubMed/MEDLINE, Scopus and EMBASE from January 1, 2006, to November 20, 2018.

Study eligibility criteria

52 studies providing detailed information on a total of 12247 patients were included. We excluded case reports and case series with less than five patients.

Study appraisal and synthesis method

We systematically assessed study quality using a bias tool and pooled consistent data.

Results

Existing data indicates milder stroke severity and smaller infarct size of acute ischemic stroke on treatment with NOAC compared to stroke occurrence on Vitamin K antagonists (VKA). Established risk factors for ischemic events also play a role in stroke while on NOACs, albeit the underlying etiology remains poorly understood. Intravenous thrombolysis and endovascular therapy seem to be safe and effective, but patient selection for recanalization therapies is challenging.

Limitations

Limited quality of published data, duplicate cases, statistical issues of data pooling, possible incomplete retrieval of identified research and reporting bias might have limited our findings.

Conclusions

Acute ischemic events despite treatment with NOAC therapy are insufficiently investigated.

Systematic review registration number

PROSPERO: CRD42018074853.