Decrease of Mortality during Deferiprone Treatments: Results from A Large Randomised Cohort of Thalassemia Major Patients Under the Auspices of the Italian Society for Thalassemia and Hemoglobinopathies

Abstract

Prognosis of thalassemia major patients has dramatically improved in the past two decades. Previous papers, including retrospective and prospective non-randomised clinical trials, suggested that mortality, due mainly to cardiac damage, was less or completely absent in patients treated with DFP alone or with associated chelation treatment. For this reason, the main aim of this study was to evaluate whether the addition of deferiprone treatment was also associated with a mortality decrease among a large randomised cohort of thalassemia major patients. Survival analysis was performed among 264 thalassemia major patients assessed for eligibility from 09/30/2000 to 01/31/2008, during a long-term multicentre randomised clinical trial. The reported chelation therapies included sequential DFP-DFO, associated DFP and DFO, DFP and DFO interventions. The survival curves were compared by gender and treatment groups using the long-rank test. Cox regression models were used to explore association between risk for death among treatments and survival time. All statistical analyses were performed by STATA 9.2. All these patients performed DFO before the date of randomisation. One death was due to a graft versus host disease (GVHD) in a patient underwent bone marrow transplantation and this patient was censored at the time of transplant. The improved survival for sequential DFP-DFO, DFP-alone, and associated DFP-DFO treated patients versus DFO-treated was statistically significant (log-rank test, χ2= 18.64; p≤0.01). In fact, no deaths were reported during DFP-alone and DFP-DFO associated treatments along a 564.5 person-years period of observation. Only one death was reported during DFP-DFO sequential treatment in a patient who had experienced 1-year before an episode of heart failure. All other ten deaths were among patients under DFO treatment. The hazard ratio for death of DFO treatment versus other treatments was 27.78 (p= 0.002). The main factors correlated with increased hazard ratio for death were cirrhosis, arrhythmia, previous episode of heart failure, diabetes, hypogonadism, hypothyroidism. No correlation between serum ferritin levels and hazard ratio for death was found.These results confirm as deferiprone alone or in addition to deferoxamine intervention is able to reduce mortality in thalassemia major patients probably because of its specific cardioprotective effect occurring independently from body iron overloading