The incidence rates of venous thromboembolism events (VTEs) in patients with BCR-ABL negative myeloproliferative neoplasms (MPN) are around 0.5-3.7% patient/year, and VTEs are one of the common causes of mortality in these patients. After the diagnosis of VTE in MPN patients, anticoagulation treatment is mandatory. However, the optimal duration is still not established. This lead to a major worry of high risk bleeding events in such patients undergoing treatment.
Wille et al. carried out a retrospective study to identify the incidence, risk factors, recurrence rate of VTE, and the optimal mode and duration of anticoagulation treatment.
The single-centre retrospective study included 529 patients from 14/05/2013 to 01/03/2018. A diagnosis of VTE was accepted only if it was positively confirmed using angiography, ultrasonography, CT, or NMR techniques. Within enrolled patients, 14.8% (78/526) patients had 99 MPN-associated VTE, and the median age at first VTE was 52.5 years. The study’s main objective was to determine the rate of recurrent thrombosis in MPN patients with VTE after discontinuation of anti-thrombotic therapy.
During a study period of 3.497 years, the study reported the rate of VTE events to be 1.7% per patient/year, where 38.4% of all VTEs appeared before or at MPN diagnosis. Additionally, in more than half of patients (55/99), VTEs occurred at uncommon sites like splanchnic or cerebral veins. MPN-associated VTE events were observed more in patients who were females (p=0.028), JAK2 positive (p=0.018), or who had polycythemia vera (p=0.009).
During the study period of 336 years after the first VTE, the recurrent rate of VTE was observed at 6% per patient/year. The prophylactic anticoagulation treatment was terminated after a median time of six months (range 1-61) in 50.7% of patients (36/71) after the first VTE events. Thirteen of these patients (13/36) had a VTE recurrence after a median of 13 months (4-168). Contrastingly, only three patients (3/35) ongoing anticoagulation had a VTE recurrence (p=0.0127).
This retrospective study demonstrates that termination of prophylactic anticoagulation treatment is associated with a high risk of re-occurrence of VTE. Therefore, longer anticoagulation treatments in MPN patients with VTE seems beneficial.
Wille K, Sadjadian P, Becker T, Kolatzki V, Horstmann A, Fuchs C, Griesshammer M. High risk of recurrent venous thromboembolism in BCR-ABL-negative myeloproliferative neoplasms after termination of anticoagulation. Ann Hematol. 2019 Jan;98(1):93-100