Despite the availability of the first automated hybrid closed-loop (HCL) system for type 1 diabetes (T1D), many youth do not use the automated feature. This 18-week prospective pilot study evaluates the impact of behavioral economic principles on 670G HCL system use in adolescents and young adults with T1D. Small monetary rewards were given for wearing/calibrating the CGM and using “auto mode.” For each of these tasks, participants received $1/day with a $3/week bonus for sustained use, with the bonus increasing by $5/week for every consecutive week the CGM is worn, up to $13/week. Participants were also rewarded for giving at least 3 meal boluses/day ($1/day), and uploading glycemic data ($5/week). However, if participants failed to perform diabetes tasks, rewards decreased to their original values. Data from 16 participants (16.2±2.5 years, 56% F) were collected at baseline, 6, 12, and 18 weeks. Of those not wearing a CGM at enrollment (88%), 86% had used a CGM previously and chose to discontinue its use. Participants used the CGM on most days, and gave at least 4 meal boluses/day consistently. HbA1c decreased by 0.5% from baseline to 6 weeks and was maintained at 12-18 weeks (p<0.05). In this pilot study of youth starting the 670G HCL system, compensation for diabetes tasks was associated with bolus adherence and improved HbA1c. Though most youth had failed CGM use in the past, CGM wear occurred >70% of time during reinforcement.


L.M. Nally: None. J. Wagner: None. M.A. Van Name: Research Support; Self; Novo Nordisk Inc. J. Sherr: Advisory Panel; Self; Bigfoot Biomedical, Eli Lilly and Company, Insulet Corporation. Consultant; Self; Lexicon Pharmaceuticals, Inc., Medtronic, Sanofi. Research Support; Self; Dexcom, Inc., Insulet Corporation. K. Zajac: None. J.L. Finnegan: None. W.V. Tamborlane: Consultant; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic MiniMed, Inc., Novo Nordisk Inc., Sanofi, Takeda Pharmaceutical Company Limited.


National Institutes of Health (1DP3DK097705-01)

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