Submitted to: Diabetes Care
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/31/2004
Publication Date: 12/1/2004
Citation: Jeha, G.S., Karaviti, L.P., Anderson, B., Smith, E.O., Donaldson, S., McGirk, T.S., Haymond, M.W. 2004. Continuous glucose monitoring and the reality of metabolic control in preschool children with type 1 diabetes. Diabetes Care. 27(12):2881-2886. Interpretive Summary: Our study shows that preschool children with type 1 diabetes have suboptimal control on twice-daily insulin injection therapy, with frequent and prolonged hypoglycemia, especially at night, lasting up to 1 h per day. The CGMS reveals trends in blood glucose that current means of evaluating the adequacy of therapy (including HbA1C and SMBG) are not able to discern. We also conclude that the HbA1C is not an ideal indicator of adequate control in this age-group but merely reflects an average of extreme highs and lows. In light of the frequency of postprandial hyperglycemia, it might be beneficial to measure postmeal glucose values in this age group. Further studies are needed to investigate whether basing clinical decision making on the CGMS results in better control in preschool children. Given the serious complications associated with hyperglycemia and neurological risks of hypoglycemia and neurological risks of hypoglycemia, especially in younger patients, failure of current therapeutic regimens using twice-daily insulin injections to achieve reasonable control is an area for concern. It is necessary to study newer types of insulin or insulin pump therapy in preschool children with type 1 diabetes in order to reduce daily glycemic excursions.
Technical Abstract: To determine using the MiniMed continuous glucose monitoring system (CGMS) 1) whether twice-daily insulin injection therapy achieves adequate control in preschool children with type 1 diabetes and 2) whether the CGMS is more informative than self-monitoring of blood glucose (SMBG) regarding glucose control and well tolerated by preschool children and their families. Ten children <6 years of age with type 1 diabetes were monitored twice using the CGMS. The distribution of glucose values was analyzed, particularly the frequency, duration, and distribution of hypoglycemia. We analyzed the accuracy of the CGMS in detecting hypoglycemia as well as the clinical relevance of the difference between CGMS and SMBG values. Although hypoglycemia was more frequent during the night (0.8 nighttime episodes • subject–1 • 24 h–1 vs. 0.3 daytime episodes • subject–1 • 24 h–1), the difference did not reach statistical significance (P = 0.07). However, nighttime episodes lasted longer than daytime episodes (1.2 vs. 0.2 h • subject–1 • 24 h–1, P = 0.006). Hypoglycemia accounted for 7% and normoglycemia for 24%, while hyperglycemia occurred 64% of the time, with postprandial hyperglycemia being an almost universal feature (94 ± 7% of all postmeal values). The CGMS correlated well with SMBG without significant clinical discrepancy. The CGMS sensitivity to detect hypoglycemia was 70% with a specificity of 99%; however, the CGMS detected twice as many total episodes as SMBG (82 vs. 40). Twice-daily insulin injection rarely achieves control in preschool children with type 1 diabetes. The CGMS is well tolerated by patients and has the advantage of revealing daily glucose trends missed by SMBG.