The relationship between changes of antithrombotic drug regimen after ischemic stroke and risks of clinical outcomes in patients with atrial fibrillation

Abstract Background Stroke prevention is central to the management of patients with atrial fibrillation (AF), but the impact of changes in antithrombotic regime following presentation with an ischaemic stroke on subsequent clinical events is unceratin. Methods From 2012 to 2018, 23,165 AF patients who experienced ischemic stroke and survived longer than 90 days after stroke were identified from Taiwan National Health Insurance Research Database. The relationships between post-stroke antithrombotic drug regimen and subsequent clinical outcomes were analyzed. Results Compared to NOACs (reference), there was a significant increase in ischaemic stroke in non-anticoagulated and antiplatelet users (both aHR approx 1.8), with no significant differences to warfarin. The same was evident for a higher mortality in non-anticoagulated and antiplatelet users (aHRs 3.441 and 1.483, respectively). Addition of antiplatelets to NOAC or warfarin resulted in non-significant differences in ischaemic stroke or mortality (Figure 1). Among 769 pateints who received NOACs before and continuously stayed on NOACs after stroke, the shifting to a different NOAC post-stroke was associated with a higher risk of ischaemic stroke (aHR 2.07) as well as the composite outcomes (aHRs between 1.359-1.849), with no difference in major bleeding, mortality or ICH (Figure 2). Conclusions Adding antiplatelet agents to NOACs for AF patients after ischemic stroke did not provide additional clinical benefits. For patients under NOACs who experienced ischemic stroke, the change to a different NOAC post-stroke was not associated with a better clinical outcome.