Characterisation of transfusion-dependent prediabetes using continuous glucose monitoring: The Haemoglycare study

Abstract

Aims: Continuous Glucose Monitoring (CGM) may help detect early dysglycemia in Transfusion-Dependent Thalassemia (TDT) patients, though previous reports suggest it may overestimate prediabetes prevalence. This study analyzed glucose-related metrics in TDT patients with negative diabetes screening tests, compared with healthy controls. A secondary objective was to assess the association between TAR140 > 6 % and clinical/laboratory characteristics of patients.

Methods: Patients resulted negative to the screening tests for glucose disorders were compared to healthy controls using CGM system for 7 days.

Results: This study involved 39 participants (19 patients, 20 controls). HbA1c was falsely elevated in patients, despite normal mean glucose and GMI. Standard deviations and coefficients of variation were higher in patients than controls. No healthy control but 7/19 (37 %) TDT patients presented the interval TAR140 > 6 %. Significant differences were observed between "really euglycaemic" TDT patients (TAR140 ≤ 6 %) and "hyperglycemic" ones (TAR140 > 6 %) in terms of GMI, mean glucose and TAR140%. Comparing the glucose metrics of TDT euglycaemic patients (TAR140 ≤ 6 %) and healthy controls, no significant difference was reported. No differences in iron overload indexes were found between the hyperglycemia and euglycemia groups.

Conclusions: CGM reliably detects prediabetes in 37 % of TDT patients. TAR140 > 6 % may serve as a diagnostic cutoff.

Keywords: Continuous glucose monitoring; Diabetes mellitus; Dysglycaemia; Iron overload; Prediabetes; Thalassemia.