Risk factors for endocrine complications in transfusion-dependent thalassemia patients on chelation therapy with deferasirox: a risk assessment study from a multi-center nation-wide cohort.

Transfusion-dependent patients typically develop iron-induced cardiomyopathy, liver disease, and endocrine complications. We aimed to estimate the incidence of endocrine disorders in transfusiondependent thalassemia (TDT) patients during long-term iron-chelation therapy with deferasirox (DFX). We developed a multi-center follow-up study of 426 TDT patients treated with once-daily DFX for a median duration of 8 years, up to 18.5 years. At baseline, 118, 121, and 187 patients had 0, 1, or ≥2 endocrine diseases respectively. 104 additional endocrine diseases were developed during the follow-up. The overall risk of developing a new endocrine complication within 5 years was 9.7% (95% Confidence Interval [CI]: 6.3-13.1). Multiple Cox regression analysis identified three key predictors: age showed a positive log-linear effect (adjusted hazard ratio [HR] for 50% increase 1.2, 95% CI: 1.1-1.3, P=0.005), the serum concentration of thyrotropin showed a positive linear effect (adjusted HR for 1 mIU/L increase 1.3, 95% CI: 1.1-1.4, P<0.001) regardless the kind of disease incident, while the number of previous endocrine diseases showed a negative linear effect: the higher the number of diseases at baseline the lower the chance of developing further diseasess (adjusted HR for unit increase 0.5, 95% CI: 0.4-0.7, P<0.001). Age and thyrotropin had similar effect sizes across the categories of baseline diseases. The administration of levothyroxine as a covariate did not change the estimates. Although in DFX-treated TDT patients the risk of developing an endocrine complication is generally lower than the previously reported risk, there is considerable risk variation and the burden of these complications remains high. We developed a simple risk score chart enabling clinicians to estimate their patients' risk. Future research will look at increasing the amount of variation explained from our model and testing further clinical and laboratory predictors, including the assessment of direct endocrine magnetic resonance imaging.

New Insights and Methods in the Approach to Thalassemia Major: The Lesson From the Case of Adrenal Insufficiency.

Background: Thalassemia Major (TM) is a complex pathology that needs a highly skilled approach. Endocrine comorbidities are nowadays the most important complications, including hypogonadism, hypothyroidism, diabetes mellitus, and bone diseases. Recent works stated that there could be a relevant prevalence of adrenal insufficiency (AI) present in TM, and this fact may become crucial, especially in case of major stressful events. Aim: Test the reliability of the standard test to diagnose AI in a group of TM and correlate it with clinical, hematological, and radiological data. Methods: We evaluated endocrine damages and the efficacy of iron chelation therapy in 102 patients affected by TM. AI was assessed by tetracosactide (Synacthen) 1 mcg iv (low-dose test, LDT) stimulation test. Patients with a subnormal response (peak cortisol < 500 nmol/L) were followed up to 5 years to check the symptoms and signs of AI. Results: We found AI in 13.7% of the population studied. We did not find any correlation between AI and all data evaluated. Only female gender seems to be a protective factor. A follow up of the patients affected by AI showed no signs of adrenal crisis, in spite of no replacement therapy. Conclusions: Our study shows a relevant prevalence of AI in TM, especially in males. The absence of an adrenal crisis, in spite of no replacement therapy, during the long-term follow up, seems to underline that current methods to evaluate AI, in TM, should consider a different and specific diagnostic test or different cut off for diagnosis.

Longitudinal changes of endocrine and bone disease in adults with ß-thalassemia major receiving different iron chelators over 5 years.

In this study, we compared the long-term effects of different iron chelation regimens (deferoxamine, deferiprone, deferoxamine + deferiprone, and deferasirox) in preventing or reversing endocrinopathy (diabetes mellitus, hypothyroidism, or hypogonadism) and bone disease (measured through DEXA) in 165 adults with ß-thalassemia major (TM) (mean age 39.9 ± 8.3 years, 43 % males). After five consecutive years of therapy, patients on deferasirox had the highest decrease in the prevalence of any endocrinopathy compared to other chelators which either had no change (deferiprone and deferoxamine) or had an increase (deferoxamine + deferiprone), p = 0.015. This was attributed to a lower proportion of patients on deferasirox developing new-onset endocrinopathy and higher proportion showing reversal of disease, compared to other chelators. A serum ferritin level of >1300 ng/mL predicted the development of new endocrinopathy (p = 0.025) while a level of <200 ng/mL predicted reversal of existing endocrinopathy (p = 0.147). A significant increase in mean BMD T-score (p < 0.001) and a considerable decrease in osteoporosis prevalence were observed in patients receiving deferasirox but not other chelators. Iron chelation therapy with deferasirox has a role in the prevention of endocrinopathy and reversal of existing disease.