Continuous glucose monitoring (CGM) systems that require calibration are known to add management burden for people with diabetes. CGM calibration likely also adds additional burden for users of automated insulin delivery, although transition between calibration-requiring and calibration-free systems has not been previously been explored qualitatively. Therefore, we aimed to evaluate the experiences of people with type 1 diabetes who transitioned from a calibration-based to a calibration-free CGM while using an Advanced Hybrid Closed Loop (AHCL) system.
Two semi-structured interviews were conducted among users of an Advanced Hybrid Closed Loop (AHCL) system. The first interview was conducted ≥20 weeks after starting the use of the calibration-requiring sensor, with the follow-up interviews conducted ≥4 weeks following Calibration free CGM use. Interviews were transcribed independently and analyzed using NVivo 12 pro. Thematic analysis was used to identify key themes and subthemes.
Fifteen participants were interviewed to reach thematic saturation. These participants had a mean age of 24.9 years (range 7-65). At baseline mean diabetes duration was 14.5 years (+/-10.9) , mean Hba1c of 54.8 mmol/mol (+/-10.2) and Time in range of 75.4% (+/-11.6). Non-Europeans represented 13% of participants and 67% were female. Participants reported a progressive improvement in digital integration, lifestyle integration and device trust following transition to calibration free CGM. They also reported more convenient calibration ,reduced overall capillary glucose assessment, increased device satisfaction and reduced burden of diabetes care following transition to calibration free devices. Negative aspects reported included perceptions of reduced sensor duration compared with CGM systems utilised in other AHCL devices and impaired integration with mobile devices.
In conclusion, calibration free CGM is an acceptable and trusted component of contemporary automated insulin delivery systems as it reduces diabetes burden while simultaneously supporting improved glycemic outcomes.