Efficacy and Safety of Direct Oral Anticoagulants in Patients With Antiphospholipid Syndrome: A Systematic Review and Meta-Analysis

Rethinking the use of direct oral anticoagulants for secondary thromboprophylaxis in patients with thrombotic antiphospholipid syndrome

Patients with thrombotic antiphospholipid syndrome (APS) are at high risk for recurrent thrombosis, and indefinite anticoagulation is recommended. Patients with APS merit indefinite anticoagulation, and vitamin K antagonists (VKAs) have historically been the standard treatment. Direct oral anticoagulants (DOACs) present an appealing alternative to VKAs. Due to their pharmacokinetic and pharmacodynamic characteristics, DOACs offer advantages over VKAs, namely the lack of need for laboratory monitoring, the usage of a fixed dosage, and the absence of significant interaction with dietary components and drugs. The efficacy and safety of DOACs in patients with APS have been studied in four phase II/III clinical trials (three with rivaroxaban and one with apixaban). These studies showed DOACs' inferiority compared to VKAs in preventing recurrent thrombosis. Recurrence was significantly greater in patients with arterial thrombotic events and a triple positivity for antiphospholipid antibodies. No differences were observed in the incidence of venous thromboembolism between both groups. Major bleeding was similar in patients treated with DOACs or VKAs. Several observational studies have reported similar results. This review aims to analyse the existing evidence on the efficacy and safety of DOACs for secondary prevention in patients with APS.

Risks Following Total Knee Arthroplasty in Patients Who Have Antiphospholipid Syndrome

BACKGROUND

Antiphospholipid syndrome (APS) is recognized as a thrombophilic autoimmune condition characterized by a tendency to develop venous thromboembolism. Total knee arthroplasty (TKA) is a prevalent procedure in patients who have advanced knee arthritis. Notably, TKA is unequivocally considered a thrombotic risk factor. However, outcomes of APS patients after TKA are still poorly documented in literature. The purpose of this study was to evaluate APS as a potential risk factor for complications after TKA.

METHODS

Using the PearlDiver Mariner database from 2010 to 2022, APS patients undergoing primary TKA were identified and compared to 10:1 matched control based on age, sex, and relevant comorbidities. A total of 7,478 patients undergoing primary TKA were analyzed, of which 683 had APS. Multivariable logistic regression analyses were done for medical complications up to 90 days and surgical complications including revision up to 2 years. Ninety-day emergency department visit and inpatient readmission were also documented.

RESULTS

Within 90 days after TKA, patients who have APS exhibited higher rates of cerebrovascular accident (adjusted odds ratio 2.04, 95% confidence interval 1.12 to 3.57; P = .014) and deep vein thrombosis (adjusted odds ratio 2.87, 95% confidence interval 1.99 to 4.06; P < .001) as compared to matched controls. No difference in surgical or nonthrombotic medical complications was observed between 2 cohorts.

CONCLUSIONS

There were significantly higher rates of stroke and deep vein thrombosis in APS patients. Our study did not find statistical differences in other surgical complications or readmissions between the 2 groups. Orthopaedic surgeons should consider appropriate prophylaxis of thrombosis in this patient population undergoing TKA perioperatively.