Growth hormone therapy for people with thalassaemia

How Age, Sex and Transfusion Affects the Incidence of Endocrine and Bone Density Disorders in Major Thalassemic Patients

Background

Beta-thalassemia major patients frequently have endocrinopathies. We tried to determine relation between demographic and transfusion factor and endocrinopathies.

Methods

Major beta-thalassemia patients (n=114 cases), 3-38 yr of age, entered this study. Female to male ratio was 51/63. Children (less than 20 yr) formed 57% of participants. Information about bone mineral density (BMD) and hormonal and biochemistry blood evaluation including fasting blood sugar (FBS), ferritin, triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), testosterone (males), and estradiol (females) entered data sheet.

Results

Sex and ferritin level showed no significant correlation with above disorders. Age significantly correlated to short stature, diabetes, low BMD at femur and neck (P, 0.031, 0.008, 0.009 and <0.001, respectively) . The risk of short stature had increased in 12 yr and older patients 7.71 times than younger patients (P= 0.008). The risk of diabetes had increased in 35 yr and older patients 26.25 times than younger patients (P= 0.03). The risk of Z-score ≤ -2 in femoral region has increased in 19 yr and older patients 5.84 times than younger patients (P= 0.002). The risk of Z-score ≤ -2 in spinal region has increased in 14 yr and older patients 17 times than younger patients (P= 0.007).

Conclusion

The main factor related with endocrinopathies was age. The correlation between age and short stature, diabetes and low BMD was positive. Therefore, we recommend early monitoring of thalassemia patients (in their late childhood and early teenage) for these complications.

New Entity-Thalassemic Endocrine Disease: Major Beta-Thalassemia and Endocrine Involvement

Beta-thalassemia (BTH), a recessively inherited haemoglobin (Hb) disorder, causes iron overload (IO), extra-medullary haematopoiesis and bone marrow expansion with major clinical impact. The main objective of this review is to address endocrine components (including aspects of reproductive health as fertility potential and pregnancy outcome) in major beta-thalassemia patients, a complex panel known as thalassemic endocrine disease (TED). We included English, full-text articles based on PubMed research (January 2017–June 2022). TED includes hypogonadism (hypoGn), anomalies of GH/IGF1 axes with growth retardation, hypothyroidism (hypoT), hypoparathyroidism (hypoPT), glucose profile anomalies, adrenal insufficiency, reduced bone mineral density (BMD), and deterioration of microarchitecture with increased fracture risk (FR). The prevalence of each ED varies with population, criteria of definition, etc. At least one out of every three to four children below the age of 12 y have one ED. ED correlates with ferritin and poor compliance to therapy, but not all studies agree. Up to 86% of the adult population is affected by an ED. Age is a positive linear predictor for ED. Low IGF1 is found in 95% of the population with GH deficiency (GHD), but also in 93.6% of persons without GHD. HypoT is mostly pituitary-related; it is not clinically manifested in the majority of cases, hence the importance of TSH/FT4 screening. HypoT is found at any age, with the prevalence varying between 8.3% and 30%. Non-compliance to chelation increases the risk of hypoT, yet not all studies confirmed the correlation with chelation history (reversible hypoT under chelation is reported). The pitfalls of TSH interpretation due to hypophyseal IO should be taken into consideration. HypoPT prevalence varies from 6.66% (below the age of 12) to a maximum of 40% (depending on the study). Serum ferritin might act as a stimulator of FGF23. Associated hypocalcaemia transitions from asymptomatic to severe manifestations. HypoPT is mostly found in association with growth retardation and hypoGn. TED-associated adrenal dysfunction is typically mild; an index of suspicion should be considered due to potential life-threatening complications. Periodic check-up by ACTH stimulation test is advised. Adrenal insufficiency/hypocortisolism status is the rarest ED (but some reported a prevalence of up to one third of patients). Significantly, many studies did not routinely perform a dynamic test. Atypical EM sites might be found in adrenals, mimicking an incidentaloma. Between 7.5–10% of children with major BTH have DM; screening starts by the age of 10, and ferritin correlated with glycaemia. Larger studies found DM in up to 34%of cases. Many studies do not take into consideration IGF, IGT, or do not routinely include OGTT. Glucose anomalies are time dependent. Emerging new markers represent promising alternatives, such as insulin secretion-sensitivity index-2. The pitfalls of glucose profile interpretation include the levels of HbA1c and the particular risk of gestational DM. Thalassemia bone disease (TBD) is related to hypoGn-related osteoporosis, renal function anomalies, DM, GHD, malnutrition, chronic hypoxia-induced calcium malabsorption, and transplant-associated protocols. Low BMD was identified in both paediatric and adult population; the prevalence of osteoporosis/TBD in major BTH patients varies; the highest rate is 40–72% depending on age, studied parameters, DXA evaluation and corrections, and screening thoracic–lumbar spine X-ray. Lower TBS and abnormal dynamics of bone turnover markers are reported. The largest cohorts on transfusion-dependent BTH identified the prevalence of hypoGn to be between 44.5% and 82%. Ferritin positively correlates with pubertal delay, and negatively with pituitary volume. Some authors appreciate hypoGn as the most frequent ED below the age of 15. Long-term untreated hypoGn induces a high cardiovascular risk and increased FR. Hormonal replacement therapy is necessary in addition to specific BTH therapy. Infertility underlines TED-related hormonal elements (primary and secondary hypoGn) and IO-induced gonadal toxicity. Males with BTH are at risk of infertility due to germ cell loss. IO induces an excessive amount of free radicals which impair the quality of sperm, iron being a local catalyser of ROS. Adequate chelation might improve fertility issues. Due to the advances in current therapies, the reproductive health of females with major BTH is improving; a low level of statistical significance reflects the pregnancy status in major BTH (limited data on spontaneous pregnancies and growing evidence of the induction of ovulation/assisted reproductive techniques). Pregnancy outcome also depends on TED approach, including factors such as DM control, adequate replacement of hypoT and hypoPT, and vitamin D supplementation for bone health. Asymptomatic TED elements such as subclinical hypothyroidism or IFG/IGT might become overt during pregnancy. Endocrine glands are particularly sensitive to iron deposits, hence TED includes a complicated puzzle of EDs which massively impacts on the overall picture, including the quality of life in major BTH. The BTH prognostic has registered progress in the last decades due to modern therapy, but the medical and social burden remains elevated. Genetic counselling represents a major step in approaching TH individuals, including as part of the pre-conception assessment. A multidisciplinary surveillance team is mandatory.

[Endocrine disorders in patients with transfusion-dependent hereditary anemias]

Often transfusions red blood cells in patients with hereditary anemias lead to iron overload, that can cause endocrine complications, such as growth retardation, hypothyroidism, hypogonadism, and disorders of carbohydrate metabolism.Clinical case 1. A boy with transfusion-dependent (TD) Diamond-Blackfan anemia at 16.3 years presented with impaired fasting glucose, growth hormone (GH) deficiency, hypogonadotropic hypogonadism; GH therapy was initiated. At the age of 16.8 years old secondary hypothyroidism, secondary hypocorticism and diabetes mellitus were diagnosed. At 17.2 years continuous glucose monitoring (CGM) detected glucose elevations up to 11.7 mmol/l. Therapy with GH and testosterone ethers was continued; levothyroxine and cortef were stopped by patient. At 17.9 years height was 163 cm; no data supporting hypothyroidism nor hypocorticism; glycaemia within goal range.Clinical case 2. A girl with TD beta-thalassemia major at the age of 11.5 years presented with GH deficiency; GH therapy has been conducted from 12.8 to 15.3 years of age. At 13.8 years retardation of pubertal development was diagnosed. At 15.0 hyperglycemia 7.2 mmol/l was detected; normal results of oral glucose tolerance test (OGTT) were observed; glycemia elevations were up to 9.5 mmol/l according to CGM data. At 16.0 height was 152 cm; because of pubertal development arrest hormone replacement therapy was prescribed.CONCLUSION. Growth, pubertal and carbohydrate metabolism disorders were diagnosed in patients with TD hereditary anemias, that confirms the necessity of regularly endocrine investigation. To detect impairment of carbohydrate metabolism investigation of fasting blood glucose, OGTT, and CGM is recommended; glycated hemoglobin measurement is not considered reasonable.

Good Clinical Practice of the Italian Society of Thalassemia and Haemoglobinopathies (SITE) for the Management of Endocrine Complications in Patients with Haemoglobinopathies

Background: The treatment of endocrinopathies in haemoglobinopathies is a continually expanding research area; therefore, recommendations supporting the appropriateness of treatments are a pressing need for the medical community. Methods: The Management Committee of SITE selected and gathered a multidisciplinary and multi-professional team, including experts in haemoglobinopathies and experts in endocrinopathies, who have been flanked by experts with methodological and organizational expertise, in order to formulate recommendations based on the available scientific evidence integrated by personal clinical experience. The project followed the systematic approach for the production of clinical practice guidelines according to the methodology suggested by the National Center for Clinical Excellence, Quality and Safety of Care (CNEC). Results: Out of 14 topics, 100 clinical questions were addressed, and 206 recommendations were elaborated on. The strength of recommendations, panel agreement, a short general description of the topic, and the interpretation of evidence were reported. Conclusions: Good Practice Recommendations are the final outcome of translational research and allow one to transfer to the daily clinical practice of endocrine complications in haemoglobinopathies.