From the Guidelines
For patients with a BMI of 40 requiring treatment for pulmonary embolism (PE), apixaban is generally considered the best DOAC option, with a recommended dosage of 10 mg twice daily for the first 7 days, followed by 5 mg twice daily for at least 3 months, as supported by the most recent evidence from 1 and 1.
Key Considerations
- Apixaban has demonstrated favorable efficacy and safety profiles in obese patients compared to other DOACs, with its pharmacokinetic properties appearing less affected by extreme body weight than rivaroxaran or dabigatran 1.
- While all DOACs have limited data in patients with BMI >40, apixaban has the most supportive evidence in this population, as seen in studies such as 1 and 1.
- Regular monitoring of renal function is important as obesity can affect kidney function over time, and some clinicians may consider checking anti-Xa levels to ensure therapeutic effect, though this isn't standard practice 1.
- Weight-based low molecular weight heparin (LMWH) remains an alternative if there are concerns about DOAC efficacy in extreme obesity, as discussed in 1 and 1.
Patient Counseling
- Patients should be counseled on the importance of medication adherence, especially with twice-daily dosing, and educated about bleeding risk signs and symptoms.
- The choice of anticoagulant should be individualized, taking into account the patient's specific risk factors, renal function, and potential drug interactions, as outlined in 1.
Evidence Summary
- The European Heart Journal study 1 provides guidance on anticoagulant therapy in patients with obesity, recommending apixaban as a suitable option for those with a BMI of 40.
- The study by Cohen et al. 1 supports the use of apixaban in patients with VTE, including those with a BMI >40, with comparable efficacy and safety to warfarin.
- The 2024 ESC guidelines for the management of atrial fibrillation 1 recommend apixaban as a first-line treatment option, with a standard dose of 5 mg twice daily, and provide guidance on dose reduction criteria.
From the Research
Direct Oral Anticoagulants (DOACs) for Pulmonary Embolism (PE) in Obese Patients
- The use of DOACs in patients with a Body Mass Index (BMI) of 40 or higher for the treatment of Pulmonary Embolism (PE) is a topic of ongoing debate 2, 3, 4, 5, 6.
- A study published in 2017 reported a case of pulmonary embolism despite rivaroxaban in an obese patient, suggesting that the standard dose of rivaroxaban may not be sufficient for patients with a BMI > 40 kg/m2 2.
- However, a retrospective matched cohort study published in 2020 found that DOACs were effective and safe for the treatment of acute venous thromboembolism (VTE) in obese patients, with no significant difference in recurrence of VTE or bleeding events compared to warfarin 3.
- A case report published in 2023 described the successful use of rivaroxaban in a morbidly obese patient with acute intermediate-high risk pulmonary embolism, achieving therapeutic anti-factor Xa levels 4.
- A review of clinical trials published in 2014 found that DOACs were as effective as and safer than standard treatment for hemodynamically stable PE, with consistent efficacy regardless of anatomical extension of PE or presence/absence of right ventricular dysfunction 5.
- A systematic review and meta-analysis published in 2021 found that DOACs were non-inferior to warfarin in reducing VTE recurrence and major bleeding events in morbidly obese patients 6.
Considerations for DOAC Use in Obese Patients
- The International Society on Thrombosis and Haemostasis recommends against the use of DOACs in patients with a BMI > 40 kg/m2 or weight > 120 kg, due to limited data on their safety and efficacy in this population 2, 6.
- However, recent studies suggest that DOACs may be effective and safe for use in obese patients, and that their use should be considered on a case-by-case basis 3, 4, 6.
- Serum concentrations of DOACs should be measured in obese patients to ensure therapeutic levels are achieved 2, 4.