Division of Neurology and MDAC study reveals an elevated stroke risk with switching oral anticoagulants in atrial fibrillation patients who developed breakthrough strokes during anticoagulation therapy

24 Jul 2023

The Division of Neurology at The Chinese University of Hong Kong (CUHK)’s Faculty of Medicine (CU Medicine) and Medical Data Analytics Centre (MDAC) conducted the world’s first population-based study to evaluate the impact of different antithrombotic approaches on patient outcomes after the first episode of ischemic stroke despite taking direct oral anticoagulants (DOACs). It revealed an elevated risk of recurrent ischemic stroke in non-valvular atrial fibrillation (NVAF) patients on alternative oral anticoagulants, especially warfarin. Adding antiplatelet agents was also not associated with reduced risk of ischemic stroke. As diabetes mellitus, cytochrome P450 or P-glycoprotein modulators and large artery atherosclerosis were associated with increased risk of stroke among these patients, precise etiological evaluation may be more important than the subsequent antithrombotic therapy in breakthrough strokes during DOAC. The findings have recently been published in the top international medical journal Neurology1.


  1. Ip YMB, Lau KK, Ko H, Lau L, Yao A, Wong GL, Yip TC, Leng X, Chan H, Chan H, Mok V, Soo YOY, Seiffge D, Leung TW. Association of Alternative Anticoagulation Strategies and Outcomes in Patients With Ischemic Stroke While Taking a Direct Oral Anticoagulant. Neurology. 2023 Jul 25;101(4):e358-e369.