Continuous subcutaneous glucose monitoring in children with type 1 diabetes

Purpose. To determine whether the use of continuous subcutaneous glucose mo nitoring will help in detecting unrecognized nocturnal hypoglycemia and in lowering hemoglobin A1c (HbA1c) levels (without increasing the risk for sev ere hypoglycemia) in children with type 1 diabetes. Methods. Eleven children with type 1 diabetes and HbA1c values consistently >8.0% were randomized either to the Continuous Glucose Monitoring System ( CGMS) group or to the control group. The CGMS group used 6 3- day sensors w ithin a 30-day period. Both groups self-monitored their blood glucose level s a minimum of 4 times daily. HbA1c levels were measured at the start, at 1 -month, and after 3 months of study. Results. The 5 children using the CGMS had 17 asymptomatic episodes (85%) o f glucose levels below 60 mg/dL (3.25 mmol/L) and 3 symptomatic episodes (1 5%) during the night in the study month. The 6 control children had 4 sympt omatic nocturnal low episodes during the month. After the 30-day period of wearing the CGMS, the 5 children had a significantly lower mean HbA1c value compared with their initial value (mean 6 standard error of the mean [SEM] decrease = .36% +/- .07%). The mean decrease for the controls was .2% +/- .2%. After 3 months, 4 of the 5 children who used the CGMS continued to hav e lower HbA1c values in comparison to their initial values (mean +/- SEM de crease = 1.04% +/- .43%). Three of the 6 control participants also had lowe r HbA1c values at 3 months (mean +/- SEM decrease for the group = .62% +/- .44%). No severe hypoglycemic events occurred in either the CGMS or the con trol groups. Conclusion. In this pilot trial, continuous subcutaneous glucose monitoring was helpful in detecting asymptomatic nocturnal hypoglycemia as well as in lowering HbA1c values without increasing the risk for severe hypoglycemia in children with type 1 diabetes.