Continuous subcutaneous glucose monitoring improved metabolic control in pediatric patients with type 1 diabetes: a controlled crossover study.

OBJECTIVE To improve metabolic control and prevent complications, both acute and late, we need to adjust treatment on the basis of the blood glucose (BG) profile, as not even the most active BG self-monitoring gives sufficient information. DESIGN We have used Continuous Glucose Monitoring System (CGMS; Medtronic MiniMed, Northridge, CA) in a controlled crossover study including 27 diabetic patients aged 12.5 +/- 3.3 (mean; standard deviation; range: 5-19) years. All patients were treated with intensive insulin therapy, 14 with multiple injections, and 13 with pumps. The patients were randomized into an open or blind study arm. Both arms wore the CGMS sensor for 3 days every 2 weeks. CGMS profiles were used in the open study arm to adjust insulin therapy at follow-up visits every 6 weeks. Both the patients and the diabetes team were masked to the CGMS profiles in the blinded arm, and insulin therapy adjustments were based solely on 7-point BG profiles performed by the patients. At 3 months the 2 study arms were crossed over. RESULTS Despite initial problems with a device new to both patients and the diabetes team, hemoglobin A(1)C decreased significantly in the open arm (from 7.70%-7.31%) but not in the blind arm (7.75%-7.65%). A total of 26/27 patients experienced daytime low subcutaneous glucose (<3.0 mmol/L;.8 episodes/day; duration 58 +/- 29 minutes; 5.5% of total time), and 27/27 patients had at least 1 nocturnal episode of low subcutaneous glucose (.4 episodes/night; duration 132 +/- 81 minutes; 10.1% of total time). CONCLUSIONS Use of CGMS facilitated an improved treatment, and patients received new insight and increased motivation. In this study, we found CGMS to be a useful tool for education and improving metabolic control.