Most patients with abdominal vein thrombosis were treated with DOACs, the incidence of major and clinically relevant non-major bleeding was low, and while the overall VTE recurrence rate after anticoagulant discontinuation was also low, the upper bound of the confidence interval indicates a non-negligible risk.
The portal vein was the most frequently affected abdominal vein in this cohort of isolated abdominal vein thrombosis patients.
Direct oral anticoagulants (DOACs) were the most commonly used anticoagulant treatment for abdominal vein thrombosis.
The 6-month cumulative incidence of major bleeding during anticoagulant treatment was low at 3.4%.
The 6-month cumulative incidence of clinically relevant non-major bleeding (CRNMB) during anticoagulant treatment was 6.7%.
The 5-year cumulative incidence of VTE recurrence after anticoagulant discontinuation was 9.6%, with the upper confidence bound indicating a non-negligible risk.
This research examined how patients with abdominal vein thrombosis (blood clots in the veins supplying the liver, intestines, and spleen) were treated and what happened to them over time. Using a Norwegian hospital registry spanning nearly 20 years, the study tracked 241 patients, about half of whom were women, with an average age of 61. A large proportion (about 36%) had cancer. The most commonly affected vein was the portal vein, which supplies blood to the liver. Nearly all patients received blood thinners, and the majority were treated with direct oral anticoagulants (DOACs) rather than the older injectable blood thinner (low-molecular weight heparin, LMWH). This research suggests that serious bleeding complications during treatment were relatively uncommon — serious (major) bleeding occurred in about 3 in 100 patients within 6 months, and less severe but still medically relevant bleeding occurred in about 7 in 100. Notably, most bleeding events happened in patients taking LMWH rather than DOACs, which may reflect why DOACs have become the preferred treatment. After stopping blood thinners, the chance of another blood clot occurring within 5 years was about 10%, but the upper end of the statistical estimate reached nearly 17%, suggesting that for some patients the risk of recurrence may be meaningful. These findings are important because abdominal vein thrombosis is uncommon and there is limited evidence to guide its management. This registry-based study provides real-world data suggesting that DOAC-based treatment is feasible and associated with low bleeding rates. The recurrence data also highlight that decisions about when to stop anticoagulation in these patients should be made carefully, particularly for those with ongoing risk factors such as cancer.
Jørgensen C, Riva N, Pettersen H, Frønæs S, Ghanima W, Tavoly M. (2026). Treatment strategies, bleeding, long-term recurrence and mortality in abdominal vein thrombosis: Findings from the TROLL registry.. Thrombosis research. https://doi.org/10.1016/j.thromres.2026.109724