Risk of Thrombosis Plummets in Older People on Hydroxyurea

Essential thrombocythemia, a myeloproliferative disorder, is associated with a high risk of thrombotic complications, especially in individuals older than 60 years and those with a previous thrombotic event. While hydroxyurea can lower platelet counts in these patients, the efficacy of this agent in reducing the risk of thrombosis has not been demonstrated.

This Italian study randomized 114 patients who had essential thrombocythemia (median platelet count, 788,000/ml3) to hydroxyurea or no myelosuppressive therapy, to see if using hydroxyurea to maintain a platelet count of less than 600,000 would reduce the incidence of thrombosis. Of the 114 studied, 85% were over 60 years of age and 46% had had thrombosis. Patients with a platelet count a…