Modern management of iron overload in thalassemia major patients guided by MRI techniques: real-world data from a long-term cohort study

Abstract

Monitoring liver and cardiac iron stores by magnetic resonance imaging (MRI) enables identifying patients at risk of organ-specific morbidity and better tailoring of iron chelation therapy in thalassemia. Nevertheless, serum ferritin (SF) remains the only tool for monitoring iron status in most resource-poor regions. In this study, we assessed the impact of using MRI techniques to guide iron chelation therapy on iron overload outcomes in a cohort of 99 patients with thalassemia major (TM, mean age at baselines 20.7 ± 6.9 years) followed from 2006 to 2019. We also assessed the ability of SF trends to predict changes in consecutive liver iron concentration (LIC) and cardiac T2* (cT2*) measurements. The most commonly used chelator was deferasirox at baseline (65%) and final (72%) assessments. Overall, patients with safe LIC values (< 7 mg/g dw) increased from 57 to 77%, and safe cT2* values (> 20 ms) increased from 72 to 86%. We obtained the most significant improvement in patients with severe and moderate liver (p = 0.006 and p < 0.001) and cardiac (p < 0.0013 and p < 0.0001) iron overload at baseline. SF trends were in the same direction in 64% of changes in LIC, but only 42% of changes were proportional. Most of the changes in SF (64%) and LIC (61%) could not predict changes in cT2*. Moreover, downward trends in SF and LIC were associated with worsening cardiac iron in 29% and 23.5% of consecutive cT2* measurements. Liver and cardiac MRI-driven oral iron chelation improved the iron status of subjects with TM and demonstrated the importance of using validated MRI techniques in critical clinical decisions.

Keywords: Cardiac iron; Iron chelation; Iron overload; Liver iron; Magnetic resonance imaging; Thalassemia major.