Previous research on hybrid closed loop (HCL) systems has demonstrated their potential to improve glycemic outcomes and reduce the burden of diabetes care for people with T1D. We sought to describe adolescents' real world use the 670G Medtronic and Tandem Control IQ (CIQ) systems including the user-specific challenges that may pose barriers to using these systems as designed. We examined the medical records of 25 adolescents aged 11-17 with HCL-capable devices (mean age = 14.4, 46% female, 96% White, non-Hispanic, mean A1C = 8.4%) , who were enrolled in an ongoing study evaluating a behavioral intervention. We extracted information from participants' medical records over a 12-month period to identify barriers to device use. Using Automode or CIQ reports, each participant was categorized as having consistent (> 70%) , inconsistent (30-70%) , or low (<30%) use. In our sample, 33% of adolescents used the 670G exclusively, 33% used the Tandem CIQ and 33% switched from the 670G to the Tandem CIQ during the study period. We observed consistent use in 52% of adolescents, inconsistent use in 16%, and low use in 32%. Participants using the 670G system averaged 20% of the time in Automode, while participants using the Tandem system were in CIQ 72% of the time. The most prevalent challenges were Reluctance to use a HCL Component, Struggling to input data into HCL, and Technology failing. In our sample, adolescents experienced fewer barriers to use and had significantly higher rates of consistent use with the Tandem CIQ in comparison to the 670G. These findings suggest that HCL systems that require less calibration and user input and are less susceptible to technical difficulties are the most feasible for adolescent use. Prioritizing adolescents' comfort with diabetes technology may promote consistent usage to reap the full benefits. Further insight into the real-world use of HLC systems in different populations is essential to determine additional barriers or disparities in consistent use of these systems.


T.Morrow: None. N.Okonkwo: None. S.S.Jaser: None.


National Institute of Diabetes and Digestive and Kidney Diseases (R01DK115545-01A1) National Institute of Diabetes and Digestive and Kidney Diseases (3R01DK115545-03S1)

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