A potentially new thromboembolic event scoring system in polycythaemia vera patients: An audit of the Hungarian Philadelphia negative chronic myeloproliferative neoplasia register.

Objective: The Hungarian National Registry for Philadelphia chromosome negative myeloproliferative neoplasms was used to analyse the thromboembolic events (TE) of Hungarian patients with polycythemia vera (PV).

Methods: Data from 351 JAK2 V617F-positive patients diagnosed with PV were collected online from 15 haematology centres reporting clinical characteristics, therapeutic interventions and thromboembolic events. TE events were evaluated before and after diagnosis based upon the Landolfi and Tefferi risk assessment scales.

Results: TE were reported on 102 patients before diagnosis and 100 during the follow-up period. Comparing to the frequency of major arterial events before PV diagnosis, we can notice a decreasing tendency after diagnosis: from 12.3% to 2.6% (p < .00003). There was no significant change in the rate of major venous events (from 5.1% to 8.5%; p = .1134) or minor arterial events (from 11.7% to 17.4%; p = .073). Bleeding events were recorded in 5.7% of patients. Despite treatment with HU + ASA, 44 patients (43.1%) with prior TE had recurrent thromboembolic complications. The particular analysis of our data revealed a new TE scoring system based on: age, gender, previous TE and iron deficiency at the time of diagnosis.

Conclusions: Our registry enables characterisation of patients with PV. The high level of recurrent TE events highlights the need for more effective and risk-adapted therapy.