Effectiveness of Continuous Glucose Monitoring in Older Adults with Type 2 Diabetes Treated with Basal Insulin

Objective: To evaluate the effectiveness and safety of real-time continuous glucose monitoring (CGM) in adults 65 years old and older with type 2 diabetes (T2D) using basal without bolus insulin. Research Design and Methods: Using data from the MOBILE randomized trial comparing CGM versus blood glucose meter (BGM) monitoring for T2D treated with basal insulin, the treatment effect in participants ≥65 years (range: 65-79 years, N = 42) was compared with the treatment effect in participants <65 years (range: 33-64 years, N = 133). Results: For participants ≥65 years old, mean change in hemoglobin A1c (HbA1c) was -1.08% in the CGM group and -0.38% in the BGM group (adjusted mean difference = -0.65% [95% confidence interval (CI) -1.49 to 0.19]). In contrast, the adjusted mean difference in HbA1c between treatment groups was -0.35% [95% CI -0.77 to 0.07] in the <65 years age group. For time in range 70-180 mg/dL (TIR), mean adjusted treatment group difference was 19% (95% CI 4 to 35, P = 0.01) in ≥65 years old participants and 12% (95% CI 4 to 19, P = 0.003) in those <65 years old. Comparable treatment group differences favoring the CGM group were observed in both the ≥65 and <65 years age groups for mean glucose and less time >180, 250, and 300 mg/dL. Hypoglycemia was low in both groups with little difference between treatment groups in both age groups. Conclusions: In this study of adults with T2D treated with basal insulin without bolus insulin, participants ≥65 years old using CGM had a greater increase in TIR and a reduction in hyperglycemia than those using BGM and the benefit appeared to be at least as great as that observed in younger adults.