Blood Coagul Fibrinolysis. 2021 Feb 9. doi: 10.1097/MBC.0000000000001021. Online ahead of print.
The current mainstay for the treatment of thrombotic antiphospholipid syndrome (APS) is anticoagulation with vitamin K antagonists (VKAs). The use of direct oral anticoagulants (DOACs) is under debate. We aimed to assess whether DOACs would be safe in APS patients presenting to the thrombosis clinic. A retrospective cohort study was conducted. All patients presenting to our thrombosis clinic between 2010 and 2017 with a diagnosis of APS taking either VKAs or DOACs were included. APS diagnosis was based on the revised Sapporo criteria. Clinical and laboratory data were collected from the electronic and physical patient files. Out of 200 patients, 81 received VKAs, and 119 DOACs. The two cohorts did not differ with regard to their initial clinical manifestation or additional prothrombotic risk factors. Only a small minority of patients was antiphospholipid antibody triple positive (VKA, 7.0% vs. DOAC, 4.2%). Number of on-treatment events was low (3 vs. 2). The hazard ratio for any thromboembolic event for patients taking DOACs was 0.78 (95% confidence interval, 0.12-5.19). Treatment with DOACs was not associated with an increased risk of recurrent thromboembolism in comparison with VKAs in this retrospective study. Our observation supports the assumption that in nontriple positive (low risk) APS patients, DOACs might be safe. Prospective data are urgently needed.