Interruption of Continuous Glucose Monitoring: Frequency and Adverse Consequences

Background: Removal of diabetes devices, including insulin pumps and continuous glucose monitoring (CGM), is a common practice due to hospital policies, interference with imaging studies, medications, and surgical interventions. Furthermore, these devices are inherently prone to malfunction, adhesive failure, and issues with insertion that can lead to a reduction in wear time. Prescription and dispensing practices provide an exact number of sensors per month without redundancy to account for the realities of daily CGM use. Methods: A RedCap survey was completed by adult patients with type 1 or type 2 diabetes (T1D or T2D) who utilize CGM followed in the Diabetes Center at Washington University in St Louis. Results: Of 384 surveys sent, 99 were completed. Participants had a mean age of 54 years, T1D 69%, female 70%, White 96%, non-Hispanic 96%, and a mean duration of diabetes mellitus (DM) 28 years. Of the cohort, 100% used CGM (80.2% Dexcom, 13.5% Freestyle Libre, 6.3% Medtronic), 61% insulin pump, and 41% Hybrid closed-loop (HCL) systems. CGM-related disruption events included device malfunction (in 85.4% of participants), insertion problems (63.5%), and falling off (61.4%). Medical care–related disruption occurred most frequently in the setting of imaging (41.7%), followed by surgery/procedures (11.7%) and hospitalization (4.4%). Adverse glycemic events attributed to CGM disruption, including hyperglycemia and hypoglycemia, occurred ≥4 times in 36.5% and 12.4% of the cohort, respectively. Conclusions: Disruption in CGM use is common. Lack of redundancy of CGM supplies contributes to care disruption and adverse glycemic events.