Student: Hassan Esmailzadah Supervisor: Associate Professor Herman Nilsson-Ehle

Abstract

β-thalassemia: Implications for iron metabolism and diabetes Background:

β-thalassemia is a genetic hemoglobinopathy with an autosomal recessive pattern of

inheritance. It causes impaired formation of the β globin chain in hemoglobin within

erythrocytes. Homozygotes or β -thalassemia major require regular blood transfusions after

birth to ameliorate anemia. The iron via blood transfusions gets stored in endocrinal organs

e.g. liver, heart, pancreas, pituitary gland.

Heterozygotes or β -thalassemia minor have a slight, but significantly microcytic anemia. β-

minor patients adapt to their anemia, do not require transfusions and are considered as

healthy carriers. The HbA1c should theoretically be lower in thalassemia patients due to

anemia and disturbance in globin chains. At the same time HbA1c is a very important blood

sample for metabolic control and thereby an interesting blood sample to study in these

patients.

Aims:

• Evaluate the presence of diabetes in patients with β-thalassemia major based on the

iron-overload hypothesis.

• Evaluate the usefulness of HbA1C for assessing glucose metabolism in β-thalassemia

minor.

• Evaluate iron-status in patients with β-thalassemia minor.

Student: Hassan Esmailzadah Supervisor: Associate Professor Herman Nilsson-Ehle

Method:

A total of 23 patients participated in the study, 18 with β-thalassemia minor (7m, 11f) and 5

with major (2m, 3f). All patients were subject to an interview on medical history, physical

examination and relevant venous blood samples.

Results:  

β-thalassemia major:

All subjects had high levels of S-ferritin. Two patients were diabetics, one of them had in addition a high BMI.

β-thalassemia minor

HbA1c was within the lower range of the reference interval. The soluble transferrin receptor (S-sTfR) was highly increased.

Conclusions:

Patients with β-thalassemia major who receive regular blood-transfusion have a higher risk of

developing diabetes mellitus type 1 due to iron accumulation in the pancreas. Insulin

resistance due to a high BMI in patients with β-thalassemia major accelerates the process of

developing diabetes. HbA1c levels in patients with β -thalassemia minor were lower than in a

healthy population. Soluble transferrin receptor (S-sTfR) levels were high among patients

with β-thalassemia minor, mostly due to an increased ineffective erythropoiesis.