Direct oral anticoagulants versus warfarin in patients with single or double antibody-positive antiphospholipid syndrome

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.

Apixaban Versus Vitamin K Antagonists in Patients With Antiphospholipid Syndrome: A Cohort Study

ABSTRACT

Current guidelines recommend that direct anticoagulants should not be used in prevention of recurrent thrombosis in patients with antiphospholipid syndrome (APS). However, except for triple-positive APS and rivaroxaban use, little evidence supports such recommendation. In a real-life cohort study, we evaluated the risk of thromboembolism and bleeding in patients with APS on apixaban versus vitamin K antagonists (VKA). We enrolled 152 patients with APS (aged 44 years [interquartile range 36-56], 83% women), including 66 patients treated with apixaban 5 mg bid and 86 with warfarin (target international normalized ratio [INR] 2-3). During a median follow-up of 53 months, we recorded venous thromboembolism, ischemic stroke, or myocardial infarction, along with major bleeding. We observed 4 thrombotic events (6.1%, 3 venous thromboembolism and 1 ischemic stroke) in patients on apixaban and 12 events (14%, 9 venous thromboembolism, 2 ischemic strokes and 1 myocardial infarction) in VKA patients. Patients with APS on apixaban had similar risk of recurrent thromboembolism compared with those on warfarin (hazard ratio [HR] = 0.327, 95% confidence interval [CI]: 0.104-1.035). Thromboembolic events occurred less commonly in statin users (8% vs. 50%, P = 0.01) and more frequently in triple-positive APS (50% vs. 22.1%, P = 0.028) and in patients with higher D-dimer at baseline ( P = 0.023); the latter difference was present in the apixaban group ( P = 0.02). Patients on apixaban had similar risk of major bleeding compared with warfarin (HR = 0.54, 95% CI: 0.201-1.448). In real-life patients with APS, apixaban appears to be similar to VKA for the prevention of thromboembolism and risk of bleeding, which might suggest that some patients with APS could be treated with apixaban.

Beta-2 Glycoprotein I IgA Isotype: An Important Consideration in Secondary Hypertension

Anti-beta-2 glycoprotein I antibodies are an important player in hypercoagulable states, including those that lead to antiphospholipid syndrome. Traditionally, assays have only detected IgG and IgM isotypes of this antibody. However, newer assays also detect the IgA isotype. The problem lies in the largely unknown significance of this IgA isotype. This paper describes a middle-aged male who presented with hypertensive emergency and was later found to have IgA anti-beta-2 glycoprotein I antibodies. He was treated with multiple anti-hypertensives, aspirin, and statin therapy. In addition to the case, we discuss the implications of this IgA isotype and how it may relate to antiphospholipid syndrome, despite not currently being included in the laboratory diagnostic criteria for the disease.

Low recurrent thrombosis rates in single positive antiphospholipid syndrome regardless of type of anticoagulation

Thrombotic antiphospholipid syndrome (TAPS) is characterized by thrombosis and persistently positive tests for antiphospholipid antibodies or lupus anticoagulant (LAC). Triple-positive APS has the highest risk of recurrent thrombosis, but no studies have focused on recurrent thrombosis in patients with single-positive TAPS. We conducted a retrospective cohort study of patients with single-positive TAPS diagnosed at Lifespan Health System, Rhode Island, to determine the rates and risk factors for recurrent thrombosis. Between January 2001 and April 2022, 128 patients were assessed who had single-positive APS (LAC = 98, aCL = 21, aβ2GPI = 9) and who had been followed for a total of 1453.8 patient-years (median follow-up 3.04 years). The initial antithrombotic regimen was warfarin in 44 %, a direct oral anticoagulant (DOAC) in 34 %, enoxaparin in 2 %, and no antithrombotic therapy or antiplatelet therapy only in 20 %. Recurrent thrombosis occurred in 16 (12.5 %) with a recurrent thrombosis rate of 3.08 per 100 patient-years. Systemic lupus erythematosus was the only variable significantly associated with recurrent thrombosis in a model adjusted for age, sex, body mass index, and type of positive APS test. All 16 patients with recurrent thrombosis were initially treated with warfarin, and, at the time of recurrent thrombosis, 13 patients remained on warfarin and three were off anticoagulation. In conclusion, the recurrent thrombosis rate in single-positive APS is low, and not all patients with a single-positive test may need indefinite anticoagulation with warfarin. Larger prospective studies are required to confirm this finding and establish optimal anticoagulation regimens for low-risk TAPS.

Retrospective, multicenter analysis of the safety and effectiveness of direct oral anticoagulants for the treatment of venous thromboembolism in obesity

BACKGROUND

Direct oral anticoagulants (DOACs) are the preferred treatment for venous thromboembolism (VTE). However, DOAC use in patients with a BMI greater than 40 kg/m2 has not been well studied despite the growing prevalence of obesity, and current literature is often underpowered.

METHODS

This multicenter, retrospective, observational study evaluated patients 18 years and older who received DOACs for acute VTE treatment. Patients receiving DOACs for recurrent VTE or for failure of another agent were excluded. The primary efficacy outcome was recurrent VTE and the primary safety outcome was major bleeding within 12 months (or one month after stopping anticoagulation therapy). A propensity score analysis was performed to balance patient characteristics and evaluate the primary endpoints by BMI group. Time-to-event outcomes were analyzed using weighted Kaplan-Meier curves.

RESULTS

There were 165 patients with a BMI of at least 40 kg/m2 and 320 patients with a BMI less than 40 kg/m2. The majority received apixaban (373, 77%). Recurrent VTE occurred in 5 (3.0%) and 13 (4.1%) of patients in the higher and lower BMI groups, respectively (adjusted OR: 0.66; 95% CI: 0.16-2.69). Major bleeding occurred in 5 (3.0%) and 15 (4.7%) of patients in the higher and lower BMI groups, respectively (adjusted OR: 1.19; 95% CI: 0.36-3.92).

CONCLUSION

There was no significant difference in VTE recurrence or major bleeding related to BMI among patients treated with DOACs. This study showed that DOACs may be a safe and effective VTE treatment option in patients with obesity.

Vintage Victory: Warfarin Versus Apixaban in the Antiphospholipid Arena

This case report explores the efficacy of warfarin compared to apixaban in managing antiphospholipid syndrome (APS), an autoimmune disorder characterized by recurrent thrombosis. We emphasize the constraints of direct oral anticoagulants (DOACs) such as apixaban in APS management. This case discusses a 41-year-old female patient with APS who did not respond to apixaban therapy. The report details her transition to warfarin, resulting in symptom resolution and no further complications, thus alluding to warfarin's effectiveness in APS management over apixaban. The case contributes to the ongoing debate on the suitability of modern DOACs in APS treatment.

Adrenal hemorrhage and non-ST elevation myocardial infarction: an antiphospholipid syndrome dilemma

Antiphospholipid syndrome (APS) can affect different organ systems, including the heart and adrenal glands. Despite being known for its prothrombotic characteristics, APS can have serious bleeding complications. Occasionally, thrombotic and bleeding episodes can present simultaneously in an APS patient. Whenever these events co-occur, resuming anticoagulation becomes a topic of debate. As such, we present the case of a 43-year-old male with triple positive antiphospholipid antibodies, indicating APS, who presented with chest pain. Anticoagulants were switched one month before presentation from warfarin to a direct oral anticoagulant, rivaroxaban. Non-ST elevation myocardial infarction, as well as new-onset left-sided adrenal hemorrhage, were diagnosed. The patient developed adrenal insufficiency; therefore, corticosteroids were administered, and warfarin was resumed to prevent further thrombotic episodes.

Choice of anticoagulation in patients with low risk antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an acquired hypercoagulable state necessitating long-term anticoagulation for secondary thrombosis prevention. Anticoagulation guidelines are predominantly based on data in high risk, triple positive patients, and favor Vitamin K antagonists over other forms of anticoagulation. The efficacy of alternative anticoagulants for secondary thrombosis prevention in low risk, single and double positive APS remains uncertain. This study aimed to assess the incidence of recurrent thrombosis and major bleeding for patient with low risk APS on long-term anticoagulation. We performed a retrospective cohort study of patients who met revised criteria for thrombotic APS between January, 2001 and April, 2021 and received care through the Lifespan Health System. Primary outcomes included recurrent thrombosis and WHO Grades 3 and 4 major bleeding. A total of 190 patients were followed over a median duration of 3.1 years. At time of APS diagnosis, 89 patients were treated with warfarin and 59 patients with a direct oral anticoagulant (DOAC). There were similar rates of recurrent thrombosis in low risk patients on warfarin versus DOACs (adjusted IRR 6.91; 95% CI 0.90-53.40, p = 0.064). Major bleeding events only occurred in low risk patients on warfarin (n = 8, log-rank p = 0.13). In conclusion, despite the choice of anticoagulation, patients with low risk APS had similar rates of recurrent thrombosis suggesting DOACs may be a potential treatment option for this cohort. There was a non-significant increase in major bleeding rates in low risk patients on warfarin versus DOACs. Study limitations include a retrospective study design and small event numbers.

Direct-acting oral anticoagulants in antiphospholipid syndrome: A systematic review

The objective of the systematic review is to analyze the efficacy of direct-acting oral anticoagulants (DOAC) in the prophylaxis of thrombosis in antiphospholipid syndrome (APS). We searched for clinical trials, cohort studies and meta-analyses published from January 1, 2012 to September 30, 2022. Articles that analyzed the efficacy of DOAC in the prevention of thrombosis recurrence, with or without comparison with antivitamin K (VKA) drugs, were selected. DOACs, specifically rivaroxaban and apixaban, were significantly less effective than VKAs in preventing recurrence of thrombosis in patients with APS and prior arterial thrombosis or the concomitant presence of two or three different antiphospholipid antibodies. The proportion of patients with severe bleeding as side effect are similar in those treated with DOAC and with VKA. The results argue against the use of DOAC in the treatment of patients with thrombotic APS.

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

Due to a high risk of recurrent thromboembolism in patients with antiphospholipid syndrome (APS), long-term anticoagulation is recommended. For decades, vitamin K antagonists (VKAs) have been the gold standard for thromboprophylaxis in these patients. Due to the widespread use of direct oral anticoagulants (DOACs) in various thromboembolic conditions and their potential advantages compared to VKAs, several studies have been conducted to evaluate their safety and efficacy in APS.

We performed a literature search using PubMed, Embase, and Cochrane databases for studies comparing DOACs to VKAs in patients with APS. Relative risk (RR) and the corresponding 95% confidence intervals (95% CI) were estimated for recurrent thromboembolic events, bleeding, and mortality.

A total of 1437 patients pooled from 12 studies were analyzed. The risk of recurrent thrombosis, especially arterial thrombosis, doubled with DOACs compared to VKAs (RR 2.61, 95% CI 1.44-4.71; p=0.001). The risk further increased in patients with a triple-positive antiphospholipid antibody profile (RR 4.50, 95% CI 1.91-10.63; p=0.0006) and with the use of rivaroxaban (RR 1.95, 95% CI 1.10-3.45; p=0.02). The risk of major bleeding and mortality were not significantly different between the two arms. A trend favoring DOACs compared to VKAs was observed for all bleeding events. 

This meta-analysis comes in agreement with previous studies and supports the use of VKAs in APS. Our study revealed that VKAs remain the gold standard for the management of APS, especially triple-positive APS. DOACs, particularly rivaroxaban, are not as effective in preventing recurrent thromboembolism in high-risk APS patients. Further studies are needed to evaluate the role of DOACs apart from rivaroxaban with a focus on their efficacy in the management of isolated or double-positive APS.

Thromboembolic Antiphospholipid Syndrome (APS): Efficacy and Safety of Different Anticoagulants-Results of the APSantiCO Registry

Background: The particular challenge in dealing with patients with thromboembolic antiphospholipid syndrome (APS) is to establish an adequate therapy regime, as patients suffer from an increased risk of relapse despite antithrombotic treatment (ATT). Vitamin K antagonists (VKA) are the standard medication of choice. The current data on the use of direct oral anticoagulants (DOAC) in APS patients remain limited. Methods: The results of the retrospective APSantiCO registry are presented. In 80 patients with APS, the efficacy and safety of different ATT regimens were analyzed. Results: At the time of inclusion, 43.8% of patients were treated with VKA and 36.3% with DOAC. Medication regimes changed several times and 279 treatment phases were further analyzed with a total treatment length of 7529 months. The incidence of recurrent arterial thrombosis was significantly larger in the DOAC group compared with the VKA group (p < 0.001), while the incidence of recurrent venous thrombosis was comparable between both groups, as was the incidence of bleedings. Heavy menstrual bleeding was the most frequently observed bleeding complication. Conclusions: The data suggest that DOAC may be an alternative to VKA for APS patients with venous thromboembolism, while VKA should be used in APS-related arterial thrombosis.

Direct oral anticoagulants versus warfarin in patients with single antibody-positive anti-phospholipid syndrome

BACKGROUND

The role of direct oral anticoagulants (DOACs) among patients with antiphospholipid syndrome (APLS) remains unclear. Warfarin has been shown to be superior to DOACs among high-risk APLS patients (particularly those with triple-positive APLS). However, it remains unknown whether DOACs may be appropriate for lower-risk patients such as those with single-positive APLS.

METHODS

We conducted a retrospective study comparing the risk of recurrent thrombosis among single-positive APLS patients treated with DOACs (apixaban or rivaroxaban), and those treated with warfarin.

RESULTS

One-hundred-forty-three single-positive APLS patients, newly started on anticoagulation following a first thrombotic event, were included. Median follow-up was 54 months (IQR 29-73 months). Ninety-one patients (64%) received warfarin and 52 patients (36%) received a DOAC. Six patients (6.6%) who received warfarin experienced a recurrent thrombotic event compared with 3 of 52 (5.8%) patients who received a DOAC (p = .845). There was no difference in event-free survival between groups (HR DOAC:Warfarin = 0.952, 95% CI 0.232 - 3.908). Major bleeding was similar in both groups.

CONCLUSIONS

These findings suggest that DOACs may be a safe and effective option for patients with single-positive APLS. Prospective studies are needed to confirm these findings.

Antiphospholipid Syndrome in a Patient With Autosomal Dominant Polycystic Kidney Disease: The Surface of the Moon

Antiphospholipid syndrome (APS) is a rare coagulopathic disorder diagnosed with a combination of clinical/imaging findings with specific antibody titer elevations over a period of 12 weeks. The following case report will discuss the unusual and challenging hospital course of a patient with extensive autosomal dominant polycystic kidney disease (ADPKD) being treated for a multi-drug resistant urinary tract infection (UTI). The patient later developed multiple deep vein thrombosis (DVT) and was found to have antiphospholipid syndrome. Warfarin, the anticoagulant of choice for antiphospholipid syndrome, has a higher likelihood of intracerebral hemorrhage than direct oral anticoagulants. This is particularly challenging since patients with autosomal dominant polycystic kidney disease have a higher propensity to develop intracranial aneurysms (ICA).