Bone disease in adult patients with β-thalassaemia major: a case-control study

Despite the extraordinary improvements carried out in diagnostic and therapeutic management of thalassaemia major over the past few decades, bone demineralization is still a common finding, even in optimally treated patients. The relationships between bone density and several clinical characteristics or hematological markers have been described, and many factors contributing to demineralization have been identified; among them endocrine complications seem to play an important role. Nevertheless, the complex etiological mechanisms of this heterogeneous osteopathy still remains incompletely clarified. While previous studies focused on the characteristics of thalassaemic patients affected from bone demineralization, we conducted a case-control study focused on thalassaemic patients free from bone disease, aimed to detect the distinctive characteristics and any possible protective feature. Among a large cohort of 150 adult patients with β-thalassaemia major, we enrolled 20 patients with normal bone mineralization and 20 patients with osteoporosis matched for gender, BMI, age at first transfusion, serum ferritin and pre-transfusional hemoglobin (Hb) levels. The differences in demographic, clinical and endocrinological profiles were investigated, correcting for physical and hematological features known as confounding variables. The comparison of the two groups for biochemical parameters and endocrine function showed a protective role of normal gonadic function and IGF-1 levels against osteoporosis, and a similar influence of hypoparathyroidism. Treatment-corrected hypothyroidism and diabetes seemed not to affect bone mineralization. In conclusion, from a different perspective our results corroborate the role of endocrinopathies in thalassaemic osteopathy, and once again underline the crucial importance of an early and multi-disciplinary intervention in preventing bone complications in thalassaemic patients.