Patients with myeloproliferative neoplasms have a significantly increased risk for arterial and venous thrombosis

Patients with myeloproliferative neoplasms (MPNs) have a significantly increased rate of arterial and venous thrombosis, with the highest rates occurring at and shortly after diagnosis. The findings of a population-based cohort study are published in Annals of Internal Medicine.

MPNs are diseases in which the bone marrow makes too many red blood cells, platelets, or excess fibrous or scar tissue in the bone marrow. Patients with myeloproliferative neoplasms are reported to be at increased risk for thrombotic events.

Using a national database in Sweden, researchers from Karolinska Institute, Stockholm, Sweden, assessed risk for arterial and venous thrombosis in 9,429 patients with MPNs compared with 35,820 matched control participants from 1987 to 2009, with follow-up to 2010. The data showed that the rate of thrombotic events was significantly elevated for patients across all age groups with MPNs of all subtypes. The 5-year cumulative incidence of thrombosis in patients with MPNs showed an initial rapid increase around the time of diagnosis, followed by gentler increases during follow-up.

According to an accompanying editorial from authors at Johns Hopkins University School of Medicine, these findings shed new light on the magnitude of thrombosis risk in patients with MPNs. The authors suggest that care of patients with MPNs should include aggressive treatment of traditional risk factors to reduce risk for arterial and venous thrombosis, regardless of age; as well as antiplatelet/anticoagulant medication and disease-specific treatment when indicated.