Background The prognosis of patients with homozygous -thalassemia(thalassemia major) has been improved by transfusion and iron-chelationtherapy. We analyzed outcome and prognostic factors among patientsreceiving transfusions and chelation therapy who had reachedthe age at which iron-induced cardiac disease, the most commoncause of death, usually occurs.
Methods Using the duration of life without the need for eitherinotropic or antiarrhythmic drugs as a measure of survival withoutcardiac disease, we studied 97 patients born before 1976 whowere treated with regular transfusions and chelation therapy.We used Cox proportional-hazards analysis to assess the effectof prognostic factors and life-table analysis to estimate freedomfrom cardiac disease over time.
Results Of the 97 patients, 59 (61 percent) had no cardiac disease;36 (37 percent) had cardiac disease, and 18 of them had died.Univariate analysis demonstrated that factors affecting cardiacdisease-free survival were age at the start of chelation therapy(P<0.001), the natural log of the serum ferritin concentrationbefore chelation therapy began (P = 0.01), the mean ferritinconcentration (P<0.001), and the proportion of ferritin measurementsexceeding 2500 ng per milliliter (P<0.001). With stepwiseCox modeling, only the proportion of ferritin measurements exceeding2500 ng per milliliter affected cardiac disease-free survival(P<0.001). Patients in whom less than 33 percent of the serumferritin values exceeded 2500 ng per milliliter had estimatedrates of survival without cardiac disease of 100 percent after10 years of chelation therapy and 91 percent after 15 years.
Conclusions The prognosis for survival without cardiac diseaseis excellent for patients with thalassemia major who receiveregular transfusions and whose serum ferritin concentrationsremain below 2500 ng per milliliter with chelation therapy.
Source Information
From the Hospital for Sick Children (N.F.O., J.H.M., A.M., G.K.) and Toronto Hospital (N.F.O., P.P.L.), University of Toronto, Toronto; the Division of Hematology-Oncology, Children's Hospital and the Dana-Farber Cancer Institute, and the Department of Pediatrics, Harvard Medical School, Boston (D.G.N., A.S.W.); and the Division of Hematology, Children's Hospital of Philadelphia, and the Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia (M.M., A.R.C.).
Address reprint requests to Dr. Olivieri at the Haemoglobinopathy Program, Division of Haematology/Oncology, Hospital for Sick Children, 555 University Ave., Toronto, ON M5G 1X8, Canada.
Deferoxamine in Thalassemia Major
Splendiani G., Tozzo C., Mazzarella V., Casciani C. U., Lucarelli G., Clift R., Angelucci E., Cazzola M., Locatelli F., De Stefano P., Olivieri N. F., Nathan D. G., Cohen A. R.
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N Engl J Med 1995;
332:270-273, Jan 26, 1995.
Correspondence
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-thalassemia (thalassemia major) has been improved by transfusion and iron-chelation therapy. We analyzed outcome and prognostic factors among patients receiving transfusions and chelation therapy who had reached the age at which iron-induced cardiac disease, the most common cause of death, usually occurs. 
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