P165 CARDIOVASCULAR RISK FACTORS AND HYPOGONADISM INFLUENCE ON CARDIAC OUTCOMES IN AN AGING POPULATION OF BETA–THALASSEMIA PATIENTS: LOOKING AT THE HEART OF THE PROBLEM

Background

β–thalassemia major (β–TM) is a hereditary genetic disease hindered by many comorbidities due to transfusion–related iron. Despite iron chelation therapy increased the life expectancy up to 50 years today, Iron–related heart disease is still a leading complication, with an expected change in cardiac disease drivers with the ageing of these patients. This study aims to evaluate the distribution and prevalence of cardiovascular risk factors in a population of thalassemia major patients, and their relationship with observed cardiovascular events and potential modifying factors.

Methods and Results

One–hundred fifty–nine β–TM patients older than 18 years of age were included in this study. Mean age was 40.9 ± 8.4 years. Low serum lipid levels with low HDL levels were noted, with 28% having diabetes mellitus and 62% with hypogonadism; Splenectomy was reported in 70%. During the observed period, 3.8% of patients had at least one episode of heart failure, 35.9% showed early signs of heart failure, 22% received a diagnosis of diastolic dysfunction, 38% had a left ventricular ejection fraction <55%, and 21.4% showed supraventricular arrhythmias. Cardiovascular risk was then assessed using two algorithms (CUORE and Pooled Cohort Risk Equation – PCRE) and was generally low despite the high burden of cardiac–related events. Patients with hypogonadism (who showed lower cardiac T2* value than those without; p < 0.001) showed a statistically significant correlation with the occurrence of cardiovascular events.

Discussion

The β–TM population has a relatively low mean age, but shows a particular metabolic profile associated with numerous comorbidities: an increased prevalence of diabetes mellitus, low HDL values and frequent hypogonadism, which tends to be associated with increased iron deposition in the myocardium. The cardiovascular risk estimated by specific algorithms (CUORE and PCRE) was generally low, probably due to the young age of the cohort and derivation pitfalls when applied to this specific population, but the prevalence of cardiac events was not negligible.

Conclusions

The chronic accumulation of iron in the heart and the specific metabolic profile, mainly observed in patients with hypogonadism, allows us to define β–TM as a condition with high cardiovascular risk from many points of view (iron–related myopathy, atherosclerosis and arrhythmias), which requires better stratification tools and specific follow–up program.

Comparative effects of deferiprone and deferoxamine on survival and cardiac disease in patients with thalassemia major: a retrospective analysis

BACKGROUND AND OBJECTIVES

Iron-induced cardiac disease remains the main cause of death in patients with thalassemia major, despite chelation therapy with deferoxamine. Deferiprone is an iron chelator that has the potential to be more effective than deferoxamine in removing intracellular iron from the heart. However, to date, no study has been designed to examine the frequency of cardiac complications and survival as the primary outcomes of a comparative study between these two chelators. This retrospective study assessed the survival and the occurrence of cardiac disease in all patients with thalassemia major treated for at least 4 years with deferiprone or deferoxamine at a single center.

DESIGN AND METHODS

The patients were, on average, 18.4 years old at the start of the review period and were followed up, on average, for 6 years. At baseline there was no significant difference in the percentage of patients with cardiac disease in the two therapy groups.

RESULTS

At the end of the study, cardiac dysfunction, expressed as worsening of pre-existing cardiac abnormality or development of new cardiac disease, was diagnosed in 2 (4%) of the 54 deferiprone-treated patients and in 15 (20%) of the 75 deferoxamine-treated patients, from the first to the last measurement (p = 0.007). The Kaplan Meier analysis of cardiac disease-free survival over the 5-year period was significantly more favorable in the deferiprone group (p = 0.003).

INTERPRETATION AND CONCLUSIONS

None of the patients treated with deferiprone died, while 3 of the patients treated with deferoxamine died because of irreversible worsening of their cardiac condition during the study period. Findings from this study suggest that long-term therapy with deferiprone provides a greater cardio-protective effect against the toxicity of iron overload than does subcutaneous deferoxamine. Formal prospective studies are warranted to confirm this effect.