Feasibility of 10-Day Use of a Continuous Glucose-Monitoring System in Adults With Type 1 Diabetes

OBJECTIVE—The purpose of this pilot study was to evaluate the feasibility of 10-day use of a transcutaneous, real-time, continuous glucose-monitoring (CGM) system. All previous reports using different CGM systems were for 3-, 5-, or 7-day use. RESEARCH DESIGN AND METHODS—On day 1, subjects received the CGM device (SEVEN System) and underwent training on proper use. Subjects returned to the clinic on days 2, 7, and 10 for in-clinic sessions. On days 2 and 7, half the subjects performed fingersticks every 15 min and the other half had Yellow Springs Instruments (YSI) samples drawn every 15 min. On day 10, all subjects participated in an 8-h in-clinic session with YSI and fingerstick testing. RESULTS—The median absolute relative difference for CGM versus YSI was 12.6, 11.3, and 14.5% on days 2, 7, and 10, respectively (P = 0.63). CGM performed better on day 10 when compared with self-monitoring of blood glucose as compared with YSI. CONCLUSIONS—This is the first study to document 10-day use of a 7-day CGM system.