From the Guidelines
For deep vein thrombosis (DVT) in super morbidly obese patients, apixaban (Eliquis) is generally considered the best direct oral anticoagulant (DOAC) option, as it has shown more consistent pharmacokinetics in extremely obese patients compared to other DOACs, with less reliance on renal clearance (only 27%) which is beneficial since obesity can affect kidney function 1. The recommended dosing is 10 mg twice daily for 7 days, followed by 5 mg twice daily for at least 3 months. Some key points to consider when using apixaban in super morbid obesity include:
- Apixaban has less data in extreme obesity compared to other patient populations, but it is still considered a viable option 1
- Rivaroxaban (Xarelto) could be considered as an alternative at 15 mg twice daily for 21 days followed by 20 mg once daily, but it has less data in extreme obesity 1
- When using DOACs in super morbid obesity (BMI >40 kg/m² or weight >120 kg), consider checking anti-Xa levels to ensure appropriate drug activity, though this isn't universally required 1
- Regular monitoring of renal function, liver function, and complete blood counts is important to minimize the risk of adverse effects 1
- If there are concerns about DOAC efficacy in an individual with extreme obesity, traditional therapy with low molecular weight heparin or warfarin remains a reliable alternative with more established dosing protocols for this population 1
From the Research
DOACs for DVT in Super Morbid Obesity
- The effectiveness and safety of direct oral anticoagulants (DOACs) in obese patients with acute venous thromboembolism (VTE) has been evaluated in several studies 2, 3, 4, 5, 6.
- A study published in 2020 found that DOACs were as effective and safe as warfarin in treating acute VTE in obese patients, with no significant difference in recurrence of VTE, pulmonary embolism, or deep vein thrombosis (DVT) events 2.
- Another study published in 2019 found that anticoagulation therapy with DOACs in morbidly obese patients may be a safe and effective alternative to warfarin for prevention of stroke or systemic embolic events, although additional studies are necessary to confirm these findings 3.
- A prospective study published in 2021 found that apixaban and rivaroxaban concentrations in obese patients treated for VTE were similar to those in non-obese patients, with a low risk of recurrent VTE and no major bleeding events 4.
- A review of pharmacokinetic, interventional, and observational study data published in 2022 found that apixaban use in obese patients does not substantially influence efficacy, effectiveness, or safety in patients with nonvalvular atrial fibrillation or VTE 5.
- A retrospective analysis published in 2024 found that DOACs were associated with a lower risk of DVT compared to warfarin in patients with obesity and VTE, with no significant differences in cumulative thromboembolic or bleeding events, pulmonary embolism, ischemic stroke, or all-cause mortality 6.
Comparison of DOACs
- Apixaban and rivaroxaban were found to have a lower risk of DVT compared to warfarin in patients with obesity and VTE 6.
- Apixaban was found to have a modest effect on pharmacokinetics in obese patients, with no significant influence on efficacy, effectiveness, or safety in patients with nonvalvular atrial fibrillation or VTE 5.
- Rivaroxaban concentrations were found to be outside the on-therapy ranges in a higher proportion of patients compared to apixaban, although this did not affect clinical outcomes 4.
Clinical Implications
- DOACs may be a safe and effective alternative to warfarin for treatment of acute VTE in obese patients, including those with super morbid obesity 2, 3, 6.
- Apixaban and rivaroxaban may be preferred over warfarin for treatment of DVT in patients with obesity, due to their lower risk of recurrent VTE and similar safety profile 6.
- Further studies are necessary to confirm the findings of these studies and to establish the optimal treatment strategy for patients with super morbid obesity and DVT.