Effects of low dose hydroxyurea treatment on patients’ quality of life in B-thalassemia/hemoglobin E disease

In clinical trials, treatment with hydroxyurea (HU) at a dosage of 20 mg/kg/day for 20 weeks has been shown to increase the production of fetal hemoglobin (Hb F) in patients with -thalassemia/hemoglobin E disease ( -thal/HbE). The objective of the present study was to determine the hematological effects and toxicity of long term treatment with HU. Twenty patients with -thal/HbE, including 6 nonsplenectomized and 14 splenectomized subjects, were treated with 10 mg/kg/day HU for 5 days/week for 36 months. Three patients were withdrawn from the study after 18 months, including two post-splenectomized patients who developed rightsided cardiac failure from chronic pulmonary thromboembolism and one who developed acute lymphoblastic leukemia. On average, HU treatment induced a 22.3% increase in absolute Hb F levels, with a reciprocal decline in Hb E levels. Hb levels, hematocrit levels and mean corpuscular volume (MCV) were slightly increased by HU treatment. Serum transferrin receptor levels were also significantly decreased by HU treatment, indicating some improvement in the degree of ineffective erythropoiesis. Reticulocytosis was decreased and a tendency towards an increase in the G /A ratio was observed. The side effects of HU therapy were minimal and no evidence of myelosuppression was observed. All patients experienced an increase in the sense of well being and an improved quality of life. In conclusion, low-dose HU therapy administered five days weekly is well tolerated and effective for increasing Hb F levels and Hb levels in patients with thalassemia/Hb E disease.