Direct oral anticoagulants after bariatric surgery—What is the evidence?

Abstract

Background Obesity is a global epidemic and bariatric surgery is used with increasing frequency to treat its complications. The extent to which bariatric surgery alters the efficacy, safety, and pharmacokinetics of direct oral anticoagulants (DOACs) is unknown. Aims In this review, we summarize the evidence supporting the use of DOACs after bariatric surgery and apply our findings to resolve several clinical cases. Materials & Methods We systematically searched MEDLINE, EMBASE, Cochrane Library, CINAHL and http://clinicaltrials.gov from January 1, 2000, to June 15, 2021 for randomized and non‐randomized studies evaluating the use of DOACs for any indication after bariatric surgery. Two reviewers independently screened titles, abstracts, and full‐text articles. Clinical and pharmacokinetic outcomes were pooled by random‐effects meta‐analysis with inverse variance weighting. We used the Newcastle‐Ottawa scale to assess risk of bias in non‐randomized studies and assessed the certainty of evidence with GRADE. Results From 2519 records, we included 28 studies (n = 3229 patients): no randomized trials, 7 cohort studies, 6 case series, and 15 case reports. Incidence rates for arterial thromboembolism, venous thromboembolism and major bleeding were: 0.73 (95% confidence interval [CI]: 0.01–5.10), 2.45 (95% CI: 0.40–7.94), and 3.40 (95% CI: 0.80‐9.36) events per 100 patient‐years, respectively. The pooled proportion of peak direct oral anticoagulant drug levels within the expected range was 58% (95% CI: 39%–74%). Conclusion There appears be substantial risk of DOAC malabsorption after bariatric surgery that could affect clinical outcomes, however the certainty of evidence was very low. PROSPERO: CRD42020202636.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

“…In patients with a BMI ≥40 kg/m 2 , a relative risk reduction of 25% for ischemic stroke (adjusted HR, 0.75 [95% CI, 0.64-0.87]; P <0.001), 57% for significant bleeding (adjusted HR, 0.43 [95% CI, 0.20-0.94]; P <0.001), and 34% for all-cause mortality (adjusted HR, 0.66 [95% CI, 0.56-0.77]; P <0.001) was observed with DOACs compared with warfarin. Although case reports exist that demonstrate expected factor Xa trough levels in patients taking a DOAC who undergo bariatric surgery, a meta-analysis of cohort studies, case series, and case reports has shown that 42% of patients who have undergone bariatric surgery had peak drug levels below the expected range. 6,7 Patients who have undergone bariatric surgery are not well represented in any of the major trials comparing DOACs with warfarin, and few observational data support DOAC use in this population. Warfarin’s therapeutic effect can be routinely monitored.…”

A Patient with Recurrent Strokes: Approach to Coagulopathy

“…There is little evidence regarding the use of DOAC in these cases, but overall, its use is preferably avoided as first-line anticoagulation in patients who have undergone these types of surgeries until more data are available. 37 38 In addition, DOACs are not effective in APS. Studies suggest a higher thrombotic risk in APS patients treated with DOACs.…”

European guidelines on peri-operative venous thromboembolism prophylaxis: first update.

“…33 However, there could be a substantial risk of malabsorption after gastric bypass, especially with rivaroxaban. [34][35][36] Some guidelines suggest that DOAC should not be used for treatment or prevention of VTE in the acute setting after bariatric surgery. 37…”

“…More recently, a randomised controlled trial compared 1 week and 4 weeks of rivaroxaban (10 mg once daily) after bariatric surgery and found only one VTE (0.4%), without differences between the short and extended protocol 33 . However, there could be a substantial risk of malabsorption after gastric bypass, especially with rivaroxaban 34–36 . Some guidelines suggest that DOAC should not be used for treatment or prevention of VTE in the acute setting after bariatric surgery 37 …”