Glycemic Outcomes with Early Initiation of Continuous Glucose Monitoring System in Recently Diagnosed Patients with Type 1 Diabetes

Background: We investigated the efficacy and safety of continuous glucose monitoring (CGM) initiation within 1 year of type 1 diabetes (T1D) diagnosis among children, adolescents, and adults. Methods: Differences in mean A1c (primary outcome) and diabetes-related emergency visits (secondary outcome) for 2.5 years between early CGM users and non-CGM users were studied among 396 newly diagnosed patients with T1D (94% children [age <18 years], 5% adults, 46% females) between January 2013 and December 2015 at Barbara Davis Center for Diabetes. The primary outcome was adjusted by age at diagnosis and gender. P < 0.05 was considered significant. Results: Gender, ethnicity, body mass index, and A1c at diagnosis were similar between the groups. Irrespective of insulin delivery methods, CGM users had a significantly greater improvement in glycemic control than non-CGM users at 1, 1.5, 2, and 2.5 years. For 2.5 years of follow-up, the multiple daily injection (MDI)+CGM group (n = 19) had 1.5% +/- 0.2% lower A1c than the MDI only group (n = 225) (7.7% +/- 0.2% vs. 9.2% +/- 0.04%, P < 0.0001), and the insulin pump (continuous subcutaneous insulin infusion [CSII])+CGM group (n = 62) had 0.7% +/- 0.1% lower A1c than the CSII only group (n = 90) (8.0% +/- 0.08% vs. 8.7% +/- 0.07%, P < 0.0001). The MDI+CGM group had significantly lower A1c than the CSII only group (7.7% +/- 0.2% vs. 8.7% +/- 0.07%, P < 0.0001). The number of diabetes-related (severe hypoglycemia or hyperglycemia) emergency department visits was significantly lower among early CGM users compared with non-CGM users (P = 0.003). Conclusion: Irrespective of insulin delivery system, early initiation of CGM within 1 year from T1D diagnosis was associated with better glucose control and fewer diabetes-related emergency visits.