Prevention of heart disease by subcutaneous desferoxamine in patients with thalassaemia major

Abstract

Cardiac siderosis from transfused iron remains the major cause of death in thalassaemia major, despite iron chelation therapy with desferrioxamine. Our aim was to determine the nature and extent of cardiac involvement and its relationship to desferrioxamine use in a group with thalassaemia major. We reviewed 76 patients with thalassaemia major and performed multiple logistic regression to analyse factors affecting cardiac involvement. Factors studied included: patient sex, age, haemoglobin, serum ferritin, total transfusions, liver iron, duration of desferrioxamine use, electrocardiograms, echocardiograms and compliance to desferrioxamine treatment. Thirty-seven patients developed heart disease. They were older (p < 0.001), began desferrioxamine later (p < 0.001), had more liver iron (p = 0.014), higher serum ferritin levels (p = 0.023) and received more blood (p = 0.018). Compared to those with optimal compliance the odds of developing heart disease were increased 10.7 times in fair compliers (p < 0.001) and 5.1 times in poor compliers (p = 0.016). However, there was no significant difference between those with fair and poor compliance. After multivariate analysis only compliance (p = 0.02) and age at desferrioxamine onset (p = 0.004) remained significant. Compliance was inversely related to liver iron (p < 0.001), serum ferritin (p < 0.001) and age at desferrioxamine commencement (p < 0.001). We conclude that late commencement of desferrioxamine and noncompliance are associated with greater iron loading and an increased risk of heart disease.