High-risk factors tied to new thrombotic events in NCPVT patients

Interactions exist between high-risk factors for thrombosis and new thrombotic events in patients with noncirrhotic portal vein thrombosis (NCPVT) with local factors, reports a study.

This retrospective study included cases of recent NCPVT associated with local factors. Researchers examined both high- and low-risk prothrombotic factors, prespecified according to the RIPORT study criteria. They used univariate and multivariate Cox models to assess the effect of different variables on the occurrence of new thrombotic events.

More than half (83 of 154, 53.9 percent) of the patients had at least one prothrombotic factor at baseline. Of these, 50 (32.5 percent) had a high-risk and 33 (21.4 percent) had a low-risk prothrombotic factor. All patients discontinued oestrogen-containing contraception.

During follow-up, 63 of 140 patients (45 percent) had at least one prothrombotic factor during follow-up. Of these, 47 (33.6 percent) had a high-risk and 16 (11.4 percent) a low-risk prothrombotic factor. After a median follow-up of 52 months, 17 new thrombotic events were reported.

New thromboses positively correlated with high-risk factors (hazard ratio [HR], 3.817, 95 percent confidence interval [CI], 1.303‒11.180; p=0.015) and inversely with recanalization (HR, 0.222, 95 percent CI, 0.078‒0.635; p=0.005) and anticoagulation (HR, 0.976, 95 percent CI, 0.856‒0.995; p=0.016).

Notably, the presence of a high-risk factor induced a new thrombotic event in 7.4 percent, 14.6 percent, 14.6 percent, and 28.8 percent of patients using anticoagulants at 1, 3, 5, and 7 years, respectively, as opposed to 21.2 percent, 21.2 percent, 58 percent, and 58 percent of those without anticoagulants, respectively.

“Our findings highlight that systematic screening for prothrombotic factors in NCPVT is needed even when associated with local factors, as it may justify long-term anticoagulation for the prevention of new intra or extrasplanchnic thrombotic events in at least one-third of cases,” the researchers said.

“The interest in long-term anticoagulation should be investigated prospectively in the absence of high-risk prothrombotic factors,” they added.