Abstract

Background: The aim was to determine whether reduced serum zinc level has a contributory effect on impairment of insulin secretion in β-thalassemic patients with transfusion-induced iron overload.
Material/Methods: Seventy thalassemia patients who received deferoxamine chelation therapy and 69 healthy individuals as the control group were evaluated. A standard oral glucose tolerance test (OGTT) was performed
and blood samples for measurement of serum ferritin, zinc, and insulin concentrations were obtained.
Results: Although the fasting serum insulin concentrations were quite similar between the patient and the control groups, serum insulin levels were signifi cantly lower in the thalassemia patients one hour and two hours after oral glucose load ingestion compared with the healthy controls. Among the
thalassemic adults, zinc defi ciency (present in 37% of patients) resulted in signifi cantly lower fasting and 1-hour post-OGTT serum insulin concentrations. The serum zinc level in patients with impaired OGTT was also considerably lower than in patients with normal OGTT.
Conclusions: These data support the assumption that zinc defi ciency might lead to an exacerbation of the inability of the pancreas to secrete suffi cient amounts of insulin in response to glucose stimulation in β-thalassemia patients. We suggest that serum zinc levels be routinely monitored in these patients as it might provide useful complementary information regarding glucose metabolism.

Keywords: Chelating Agents - therapeutic use, Adolescent, Deferoxamine - therapeutic use, Ferritins - blood, Glucose - metabolism, Glucose Tolerance Test, Homeostasis, Insulin - metabolism, Siderophores - therapeutic use, Zinc - deficiency, beta-Thalassemia - metabolism