Portuguese Observational Study of Ischaemic Stroke in Patients Medicated with Non-Vitamin K Antagonist Oral Anticoagulants

Introduction: Clinical trials and subsequent meta-analyses showed advantages of non-vitamin K antagonists oral anticoagulants (NOACs) over vitamin K antagonists (VKAs) in patients with non-valvular atrial fibrillation. The impact of preadmission anticoagulation in acute ischaemic stroke (AIS) has not been established.

Objective: To compare functional outcome of patients with AIS with preadmission NOACs vs. VKAs.

Methods: A retrospective analysis was conducted on consecutive AIS patients under oral anticoagulation (VKAs or NOACs) admitted in 4 Portuguese hospitals within a period of 30 months. Two primary outcomes were defined and compared between VKA and NOAC groups: symptomatic intracerebral hemorrhage transformation (sICH) and modified Rankin Scale (mRS) at 3 months.

Results: Four hundred sixty-nine patients were included, of whom 332 (70.8%) were treated with VKA and 137 (29.2%) with NOAC. Patients' median age was 78.0 and 234 (49.9%) were male. NOAC-treated patients had a higher median CHA2DS2-VASc score than those under VKA (5.0 vs. 4.0, p = 0.023). The two primary outcomes showed no statistical differences between the VKAs' group and the NOACs' group (sICH: 5.4 vs. 5.4% [p = 0.911]; mRS at 3 months: 3.0 vs. 3.0 [p = 0.646], respectively).

Conclusion: Preadmission anticoagulation with NOACs in AIS has a functional impact similar to that of VKAs.