Evaluation of continuous glucose monitoring system for detection of alterations in glucose homeostasis in pediatric patients with β-thalassemia major

Abstract

Background Disturbances of glucose metabolism are common in β‐thalassemia major (β‐TM). Aim This study was conducted to assess the pattern of glucose homeostasis in pediatric β‐TM patients comparing oral glucose tolerance test (OGTT) and continuous glucose monitoring system (CGMS). Methods Two‐hundred β‐TM patients were studied and those with random blood glucose (RBG) ≥7.8 mmol/L (140 mg/dL) were subjected to OGTT, insertion of CGMS and measurement of fasting C peptide, fasting insulin, and hemoglobin A1c (HbA1c). Results Twenty patients (10%) had RBG ≥ 7.8 mmol/L. Using OGTT, 6 out of 20 patients (30%) had impaired glucose tolerance (IGT) while 7 (35%) patients were in the diabetic range. CGMS showed that 7/20 (35%) patients had IGT and 13 (65%) patients had diabetes mellitus (DM); 10 of the latter group had HbA1c readings within diabetic range. The percentage of diabetic patients diagnosed by CGMS was significantly higher than that with OGTT (P = 0.012). Serum ferritin was the only independent variable related to elevated RBG. All β‐TM patients with DM were non‐compliant to chelation therapy. Conclusions The use of CGMS in the diagnosis of early glycemic abnormalities among pediatric patients with β‐TM appears to be superior to other known diagnostic modalities.

The effects of iron overload, insulin resistance and oxidative stress on metabolic disorders in patients with β- thalassemia major

“…Our study had two main limitations. The first was the use of FBS instead of methods with higher diagnostic capabilities including continuous monitoring of serum glucose and oral glucose tolerance test (OGTT) for the detection of glycemic abnormalities [39]. However, these methods are time-consuming and cause some inconvenience to the patients and we failed to use them.…”

Indicators of glucose dysregulation and the relationship with iron overload in Chinese children with beta thalassemia major

“…Moreover, endocrine complications, due to iron overload, account for significant morbidity, such as diabetes mellitus (DM). 1,2 Hemoglobin A1c (HbA1C), which is important for evaluating glucose metabolism, can reflect the average blood glucose status from the previous 2-3 months. However, HbA1c is susceptible to other factors, such as erythropoiesis, hemoglobin disease, glycosylation levels, and erythrocyte longevity.…”

Investigation and Management of Endocrinopathies in Thalassaemia Major

“…El-Samahy et al studied 20 beta thalassaemia patients with random blood glucose >7.8 mmol, who then had OGTT and CGMS. OGTT detected 6/20 patients (30%) who had impaired glucose tolerance and 7/20 (35%) patients who were in the diabetic range, while CGMS found that 7/20 (35%) patients had IGT and 13/20 (65%) had frank diabetes mellitus [64].…”

“…Kanbour et al found that patients with very high liver iron concentration (LIC) (>30 mg Fe/gm dry liver) were more likely to have a higher prevalence of impaired fasting glucose when compared to those with lower LIC (p = 0.044) [55]. The use of continuous glucose monitoring (CGMS) in detecting glucose intolerance and diabetes mellitus has also been studied, with CGMS found to be superior when compared to OGTT (p = 0.012) [64]. El-Samahy et al studied 20 beta thalassaemia patients with random blood glucose >7.8 mmol, who then had OGTT and CGMS.…”