Incremental Value of Continuous Glucose Monitoring When Starting Pump Therapy in Patients With Poorly Controlled Type 1 Diabetes

Abstract

OBJECTIVE: To compare the improvements in glycemic control associated with transitioning to insulin pump therapy in patients using continuous glucose monitoring versus standard blood glucose self-monitoring. RESEARCH DESIGN AND METHODS: The RealTrend study was a 6-month, randomized, parallel-group, two-arm, open-label study of 132 adults and children with uncontrolled type 1 diabetes (A1C >or=8%) being treated with multiple daily injections. One group was fitted with the Medtronic MiniMed Paradigm REAL-Time system (PRT group), an insulin pump with integrated continuous subcutaneous glucose monitoring (CGM) capability, with instructions to wear CGM sensors at least 70% of the time. Conventional insulin pump therapy was initiated in the other group (continuous subcutaneous insulin infusion [CSII] group). Outcome measures included A1C and glycemic variability. RESULTS: A total of 115 patients completed the study. Between baseline and trial end, A1C improved significantly in both groups (PRT group -0.81 +/- 1.09%, P < 0.001; CSII group -0.57 +/- 0.94%, P < 0.001), with no significant difference between groups. When the 91 patients who were fully protocol-compliant (including CGM sensor wear >or=70% of the time) were considered, A1C improvement was significantly greater in the PRT group (P = 0.004) (PRT group -0.96 +/- 0.93%, P < 0.001; CSII group -0.55 +/- 0.93%, P < 0.001). Hyperglycemia parameters decreased in line with improvements in A1C with no impact on hypoglycemia. CONCLUSIONS: CGM-enabled insulin pump therapy improves glycemia more than conventional pump therapy during the first 6 months of pump use in patients who wear CGM sensors at least 70% of the time.