[Usefulness of continuous glucose monitoring system (CGMS) in monitoring glycaemic profile in small children with diabetes type 1]

Abstract

Background: Improved methods of diabetes therapy result in a near normoglycaemic state in many patients. This leads however unfortunately to more frequent hypoglycaemic incidents. Particularly small children, whose nervous system is not fully mature, are at high risk of central nervous system damage in case of hypoglycaemia. A new method of detail monitoring of glycaemia provides CGMS system.

Objectives: The aim of the study was to compare the glycaemic profile, with high attention to hypoglycaemia in groups of young and older children with diabetes type 1, using CGMS and routine glucose meter.

Material and methods: We studied 32 children with diabetes type 1. Children were divided into groups: group I--small children, n=17 (<7 yrs of age), mean age 5,8 years, with disease duration--2,46 years, with mean HbA1c level--7,22%, and group II--older children, n=15 (>10 years of age), mean age--12 years, with disease duration--3 years, with HbA1c level--7,21%. Continuous glucose monitoring system (CGMS), by MiniMed, was applied in outpatient or hospital conditions, after short training of patient and parents; together with routine glucose meter measurements, 4-8 times/24 hours. In 9 patients from small children group CGMS was repeated after 2 months.

Results: Hypoglycaemic incidents detected with CGMS were similar in both groups: 4,6 in I group vs. 4,2 in II group (ns). Hypoglycaemic incidents found with meter were lower in I group--1,6 vs. 2,3 in II group (ns). Mean hypoglycaemic time/24 hour was longer in small children group: 101 min vs. 74 min in group II (p<00,05). In I group we found higher number of hypoglycaemic incidents during the night compared to group II--1,7 vs. 0,8 (p<00,05) and longer duration of night hypoglycaemia: in I group--56 min vs. 32 min in group II (p<00,05). Repeated CGMS study in 9 children from I group revealed decreased mean time of hypoglycaemia/24 hours from 134 min/24 h to 90 min/24 h (p<00,05) and decreased time of night hypoglycaemia from 65 min to 40 min (p<00,05), with a comparable number of hypoglycaemic incidents. Hypoglycaemic incidents found with routine meter measurements in small children were 1,6 vs. 4,6 hypoglycaemia found with CGMS (p<00,05), in the older children group routine measurement found 2,3 hypoglycaemia vs. 4,2 detected with CGMS (ns).

Conclusions: 1. CGMS can be particularly usefull in monitoring glucose profile and detecting hypoglycaemia incidents, mainly nocturnal in small children. 2. CGMS allows to verify meal dose of insulin and to decrease postprandial hyperglycaemia. 3. Modification of insulin therapy on the base of CGMS helps to decrease the time of hypoglycaemia and hyperglycemia, particularly during the night.