Glucose homeostasis in Egyptian children and adolescents with β-Thalassemia major: Relationship to oxidative stress.

Abstract

Background:Oxidative stress in children with β-thalassemia may contribute to shortened life span of erythrocytes and endocrinal abnormalities.Aim:This study was aimed to evaluate glucose homeostasis in Egyptian children and adolescents with β-thalassemia major and its relation to oxidative stress.Materials and Methods:Sixty children and adolescents with β-thalassemia major were studied in comparison to 30 healthy age and sex-matched subjects. Detailed medical history, thorough clinical examination, and laboratory assessment of oral glucose tolerance test (OGTT), serum ferritin, alanine transferase (ALT), fasting insulin levels, plasma malondialdehyde (MDA) as oxidant marker and serum total antioxidants capacity (TAC) were performed. Patients were divided into two groups according to the presence of abnormal OGTT.Results:The prevalence of diabetes was 5% (3 of 60) and impaired glucose tolerance test (IGT) was 8% (5 of 60). Fasting blood glucose, 2-hour post-load plasma glucose, serum ferritin, ALT, fasting insulin level, homeostatic model assessment for insulin resistance index (HOMA-IR) and MDA levels were significantly elevated while TAC level was significantly decreased in thalassemic patients compared with healthy controls (P < 0.001 for each). The difference was more evident in patients with abnormal OGTT than those with normal oral glucose tolerance (P < 0.001 for each). We also observed that thalassemic patients not receiving or on irregular chelation therapy had significantly higher fasting, 2-h post-load plasma glucose, serum ferritin, ALT, fasting insulin, HOMA-IR, oxidative stress markers OSI and MDA levels and significantly lower TAC compared with either those on regular chelation or controls. HOMA-IR was positively correlated with age, serum ferritin, ALT, MDA, and negatively correlated with TAC.Conclusions:The development of abnormal glucose tolerance in Egyptian children and adolescents with β--thalassemia is associated with alteration in oxidant-antioxidant status and increase in insulin resistance.Recommendation:1- Glucose tolerance tests, HOMA-IR, and MDA should be an integral part of the long-term follow-up of children and adolescents with β-thalassemia major. 2- Regular iron chelation and antioxidant therapy should be advised for thalassemic patients to improve glucose hemostasis.