The diagnosis of hypoglycemia unawareness in children and adolescents with continuous subcutaneous glucose monitoring systems and the impact of structured education

Seeking strict normoglycemia in type 1 diabetes mellitus increases the risk of hypoglycemia, exposing to hypoglycemia unawareness. Hypoglycemia unawareness (HU) is defined as the occurrence of hypoglycemic symptoms directly without autonomic symptoms. This study is designed to determine the incidence of HU in children and adolescents with continuous subcutaneous glucose monitoring system and to assess the effect of structured education to improve awareness. Materials and Methods: In this prospective controlled quantitative study, randomly selected 39 Type 1 diabetic children and adolescents with a diabetes duration of at least 5 years were included. Continuous Subcutaneous Glucose Monitoring System, Medtronic iPro®2 was used to determine HU. A diary was kept for the symptoms of hypoglycemia. Hypoglycemia was defined as sensor glucose level < 70 mg/dl. Patients who were diagnosed with HU initially undergone a structured education and after 3 months CGMS was used again in HU patients to detect the influence of education. Results: Thirty seven type 1 diabetic patients (mean age 13,8 ± 2,42 years, 43 % male, mean diabetes duration 7,67 ± 1,66 years, mean hemoglobin A1c 8.0 ± 1.2%) participated in the study. 25 patients were on MDI therapy while the rest were on continuous insulin infusion therapy (CSII). 24,3% (n=9) of the patients were diagnosed as having HU with CGMS. 6 of them were on MDI, 3 on CSII. 27.3% of the patients with a diabetes duration of 5-8 years and 72.7 % of the patients with a duration of 8-11 years had HU. Mean HbA1c of the patients with and without HU within the preceding year was 7,9%±0,97 % and 8,4±1,2 % respectively (p:0, 230). HU cases were < 70 mg/dl for 11,44±5,12 hours while patients without HU were < 70 mg/dl for 1,93±2,23 hours at the beginning of the study (p:0,00). AUC for hypoglycemia and number of low excursions were; 1,81±0,95 and 8,33±3,60 for HU group and 0,23±0,31 and 2,68±2,05 for the without HU group respectively at the beginning of the study (p:0,00). HU patients were hypoglycemic for 4,44±3,78 hours, AUC for hypoglycemia was 0,43±0,47 and the number of low excursions were 5,22±3,99. Though AUC and hypoglycemia duration statistically decreased compared to the initial findings, the number of hypoglycemic excursions did not change with structured education. Conclusions: HU is commonly seen in patients with type 1 diabetes mellitus. Continuous subcutaneous glucose monitoring system is effective in determining HU. Rate of HU can be reduced by structured education. Key words: Type 1 Diabetes Mellitus, Hypoglycemia, Hypoglycemia Unawareness, Structured Education, Continous Glucose Measurement Systems