Endocrine Abstracts

Aims: Endocrine deficiencies are common complications of thalassaemia major. Our haematology department serves one of the UK’s largest populations of thalassaemia patients. We assessed our thalassaemia major patients’ endocrine status and factors associated with endocrinopathies.

Methods: Retrospective analysis of our thalassaemia major patients on active follow-up in April 2010. Parameters such as age, gender, hepatitis C infection, compliance with chelation therapy, mean ferritin over 10 years, highest Ferriscan liver iron concentration from 2007 to 2010, lowest cardiac magnetic resonance T2* value between 1999 and 2010 were tested for independent association with each endocrinopathy, using multivariate analysis.

Results: Data was reviewed from 102 thalassaemia major adults (52 females, 50 males) with median age 35.5 years (range 17–58 years).

Clinical hypothyroidism was recorded in 11.8% of patients (9.8% primary, 2.0% secondary), subclinical hypothyroidism in 2.9%, normal thyroid status in 85.3%. Prevalence of hypoparathyroidism was 13.7%. Hypothyroidism and hypoparathyroidism were not independently related with any of the parameters tested.

Hypogonadotrophic hypogonadism was recorded in 64.7% and primary hypogonadism in 2.9%. Hypogonadism was associated with myocardial iron loading. For every 1 ms decrease in the lowest cardiac magnetic resonance T2* value between 1999 and 2010, there was a 4.4% (95% CI 0.8–7.8%, P value 0.016) increase in odds of having hypogonadism.

No cases of GH deficiency or glucocorticoid deficiency were documented.

Conclusions: A significant proportion of thalassaemia major patients have endocrine deficiencies. Ferritin concentrations are not a reliable predictor of endocrine deficiency. Patients with evidence of cardiac iron loading over the previous 11 years were more likely to have hypogonadism. This suggests that tissue iron loading is an important factor leading to hypogonadism. Controlling total body iron in thalassaemia major is critical in preventing damage to multiple major organs.