Non-Vitamin K Oral Anticoagulants in Stroke Patients: Practical Issues

Temporal Trends in Pharmacological Stroke Prevention in Patients with Acute Ischemic Stroke and Known Atrial Fibrillation

INTRODUCTION

Oral anticoagulation (OAC) substantially reduces stroke risk in patients with atrial fibrillation (AF) at risk for stroke. Whether non-vitamin K-dependent oral anticoagulants (NOACs) improve OAC use in stroke prevention requires investigation.

METHODS

To investigate temporal trends of OAC use in patients with known AF pre-stroke, we retrospectively analyzed records of 6,803 stroke patients admitted in 2003-2004 (n=1,496), 2008-2010 (n=1,638) or 2013-2015 (n=3,669) to the Charité-Universitätsmedizin Berlin, Germany. Adjusted regression models were used to identify factors associated with OAC use.

RESULTS

Of 1,209 AF patients (mean age 79 years, 55.9% female) with given indication for OAC according to the CHADS₂/CHA₂DS₂-VASc score, 484 (40.0%) were anticoagulated prior to the index stroke, 458 (37.9%) received antiplatelets and 236 (19.5%) had no antithrombotic medication. Compared to 2003-2004 and 2008-2010, there was a higher rate of pre-admission OAC in 2013-2015 (28.2% vs. 49.6%, p<0.001). After adjustment for possible confounders, factors associated with OAC pre-admission were young age (OR 0.74 per decade [95%CI 0.64-0.85]), previous stroke/TIA (OR 1.29 [95%CI 1.00-1.67]), absence of heart failure (OR 0.63 [95%CI 0.47-0.85]) and admission in 2013-2015 (OR 2.45 [95%CI 1.91-3.15]). Prescription of OAC at hospital discharge increased from 2003-2010 compared to 2013-2015 (45.2% vs. 69.5%, p < 0.001).

CONCLUSIONS

Irrespective of temporal trends and despite given indication, more than half of all patients with known AF were not anticoagulated prior to the index stroke. In the NOAC era, there was an increase in OAC intake pre-stroke and a higher rate of OAC prescription at hospital discharge in stroke survivors with known AF.

[Second look: practical diagnostic and therapeutic checks in neurorehabilitation]

Post-acute inpatient neurorehabilitation facilities are increasingly treating patients who are not only severely ill and multimorbid but who are also referred from non-neurological departments. These patients are still often medically unstable so that the previous diagnostics and treatment must be reevaluated and when necessary adapted or supplemented. Certain interdisciplinary diagnostic and therapeutic problems, such as antithrombotic therapy, regularly reoccur. This article presents these problems in a checklist fashion, which should provide indications in individual cases when previously carried out measures need to be questioned and adapted.

Timing of Initiation of Oral Anticoagulation after Acute Ischemic Stroke in Patients with Atrial Fibrillation

Patients with atrial fibrillation (AF) who suffer an acute ischemic stroke are at risk for both hemorrhagic transformation and recurrent ischemic stroke in the acute post-stroke period. Oral anticoagulants are recommended for secondary stroke prevention in patients with AF. The optimal time to initiate anticoagulant therapy after acute ischemic stroke in patients with AF is uncertain. There is concern that early initiation increases the risk of hemorrhagic transformation, whereas delayed initiation leaves the patient at risk for recurrent ischemic stroke. In this article, we provide a review of the risk of hemorrhagic transformation of acute ischemic stroke as well as review the literature and major guidelines addressing the timing of anticoagulation initiation after an acute ischemic stroke in patients with AF. Relevant articles published from 1990 to the present were identified using the PubMed and Embase databases. The majority of available literature is observational data. Large ischemic lesions, cerebral microbleeds, thrombolytic therapy, and other clinical factors may increase the risk of hemorrhagic transformation of an acute ischemic stroke. Parenteral anticoagulation within 48 hours is associated with an increased risk of hemorrhagic transformation and is not recommended. Insufficient data exist to support the safety of routine oral anticoagulant (direct oral anticoagulants or warfarin) initiation within 48 hours of an acute ischemic stroke. Direct oral anticoagulant initiation within 2 days of an acute ischemic stroke is associated with a 5% rate of hemorrhagic transformation. Infarct size and presence of hemorrhage are important factors in identifying the optimal time to initiation and should guide decisions when available. A recommended framework for patient decision making is provided. Randomized controlled trials in this area are needed to identify the optimal timing of anticoagulation initiation, and such trials are under way.