Continuous Glucose Monitoring in Older Adults With Type 1 and Type 2 Diabetes Using Multiple Daily Injections of Insulin: Results From the DIAMOND Trial

Abstract

Objective: The objective was to determine the effectiveness of real-time continuous glucose monitoring (CGM) in adults ≥ 60 years of age with type 1 (T1D) or type 2 (T2D) diabetes using multiple daily insulin injections (MDI). Methods: A multicenter, randomized trial was conducted in the United States and Canada in which 116 individuals ≥60 years (mean 67 ± 5 years) with T1D (n = 34) or T2D (n = 82) using MDI therapy were randomly assigned to either CGM (Dexcom™ G4 Platinum CGM System® with software 505; n = 63) or continued management with self-monitoring blood glucose (SMBG; n = 53). Median diabetes duration was 21 (14, 30) years and mean baseline HbA1c was 8.5 ± 0.6%. The primary outcome, HbA1c at 24 weeks, was obtained for 114 (98%) participants. Results: HbA1c reduction from baseline to 24 weeks was greater in the CGM group than Control group (−0.9 ± 0.7% versus −0.5 ± 0.7%, adjusted difference in mean change was −0.4 ± 0.1%, P < .001). CGM-measured time >250 mg/dL ( P = .006) and glycemic variability ( P = .02) were lower in the CGM group. Among the 61 in the CGM group completing the trial, 97% used CGM ≥ 6 days/week in month 6. There were no severe hypoglycemic or diabetic ketoacidosis events in either group. Conclusion: In adults ≥ 60 years of age with T1D and T2D using MDI, CGM use was high and associated with improved HbA1c and reduced glycemic variability. Therefore, CGM should be considered for older adults with diabetes using MDI.