Direct oral anticoagulants vs. vitamin K antagonists in patients with antiphospholipid syndrome: a systematic review and meta-analysis

Optimal treatment regimen for patients with antiphospholipid syndrome (APS) remain unclear. Therefore, the authors sought to compare the outcomes of vitamin K antagonists (VKAs) vs. direct oral anticoagulants (DOACs) in patients with APS. METHODS: MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials comparing efficacy and safety of VKAs and DOACs inhibitors in patients with APS. Recurrent thrombosis, all-cause mortality, stroke, adverse reactions, and bleeding were among outcomes of interest. Mantel–Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95% CIs. RESULTS: The analysis included 625 patients from four randomized controlled trials and one post hoc analysis. Meta-analysis showed statistically non-significant difference between DOACs inhibitors and VKAs in the recurrent thrombosis risk (arterial or venous) [RR 2.77 (95%, CI 0.79, 9.65); P=0.11, I(2)=50%]. Consistent results were revealed among patients with the previous history of arterial thrombosis [RR 2.76 (95% CI 0.93, 8.16); P=0.75, I(2)=0%], venous thrombosis [RR 1.71 (95% CI 0.60, 4.84); P=0.31, I(2)=15%] and patients who were triple antiphospholipid positive [RR 4.12 (95% CI 0.46, 37.10); P=0.21, I(2)=58%]. DOACs inhibitors were significantly associated with increased risk of stroke [RR 8.51 (95% CI 2.35, 3.82); P=0.47, I(2)=0%]. CONCLUSION: DOACs exhibited increased risk of stroke among patients with APS. In addition, although not significant, the higher RRs among patients on DOACs may indicate higher risk of thrombotic events associated with DOACs.