Introduction: Patients undergoing flow diversion (FD) may require chronic anticoagulation (AC) due to underlying comorbidities. There is limited literature on the safety and efficacy of FD in these patients. Our study analyzes outcomes of FD among patients receiving AC to those without AC. Methods: This retrospective study included patients who underwent FD at nine participating institutions from January 2018 to January 2024. Patients were dichotomized based on their history of AC. Outcomes of interest were angiographic occlusion, retreatment, hemorrhagic complications and functional dependence on follow-up. Results: Of 308 total patients, 65 (21.1%) were on oral anticoagulation prior to FD, while 243 patients (88.9%) were not on AC prior to FD. The cohort on AC was older (mean age: 64.4 vs. 57.2 years, P<0.001), had a greater proportion of patients with hypertension (69.2% vs. 46.1%, P<0.001) and baseline functional dependence (13.8% vs. 4.9%, P<0.05). The cohort on AC also had a smaller proportion of female patients (72.3% vs. 84%, P<0.05), patients who were on antiplatelets prior to admission (30.8% vs. 53.9%, P<0.001), previously treated aneurysms (18.5% vs. 30.9%, P<0.05) and ruptured aneurysms (4.6% vs. 16%, P<0.05). After inverse probability treatment weighting analysis, rates of angiographic occlusion (aOR: 0.69, 95% CI: 0.36- 1.32), P= 0.27), retreatment (aOR: 1.56, 95% CI: 0.42- 5.76, P= 0.507) and functional dependence (aOR: 4.33 (0.92- 20.43, P= 0.065) were comparable across cohorts. Patients who received AC had 0.11-fold lower odds (95% CI: 0.01- 0.94, P= 0.045) for hemorrhagic complications (aOR: 0.11, 95% CI: 0.01- 0.94, P= 0.045). Conclusions: FD in patients on AC offers rates of angiographic occlusion comparable to those without AC, with no increased rates of hemorrhagic complications, retreatment and functional dependence.
Roy et al. (2026) studied this question.