Acute effects of blood transfusion on insulin sensitivity and pancreatic β-cell function in children with β-thalassemia/hemoglobin E disease

Objective: To assess the acute effects of blood transfusion on insulin sensitivity and pancreatic β-cell function in thalassemia patients. Methods: Fifty children and adolescents with β-thalassemia/HbE disease were enrolled in a prospective cohort study. Hemoglobin, serum ferritin and oral glucose tolerance test (OGTT) were performed prior to, and one week after blood transfusion. Insulin sensitivity indices [homeostatic model assessment (HOMA) of insulin resistance (HOMA-IR), whole body insulin sensitivity index (WBISI)] and β-cell function indices [HOMA of β-cell function (HOMA-β), insulinogenic index (IGI), and disposition index (DI)] were calculated from glucose and insulin levels obtained during the OGTT. Results: Following blood transfusion, hemoglobin and serum ferritin increased significantly; 8.5 to 10.1 g/dL (p<0.001) and 1764 to 2160 ng/mL (p<0.001), respectively. β-Cell function indices also increased significantly [median HOMA-β: 74.3 vs. 82.7 (p=0.033); median IGI: 59.6 vs. 79.3 (p=0.003); median DI: 658 vs. 794 (p=0.01)]. However, the insulin sensitivity index (WBISI) tended to decrease and the insulin resistance index (HOMA-IR) tended to increase although this did not reach significance. Multivariate analysis showed that pre-transfusion serum ferritin was the major factor negatively associated with WBISI and positively associated with HOMA-IR, but pre-transfusion hemoglobin had no significant association with insulin sensitivity indices post-transfusion. Conclusion: This study demonstrated that acute increases in serum ferritin and hemoglobin following blood transfusion in patients with thalassemia might contribute to an increase in insulin secretion and to a trend towards increased insulin resistance.