A PILOT STUDY OF YOUTH WITH T1D INITIATING USE OF A HYBRID-CLOSED LOOP SYSTEM WHILE RECEIVING A BEHAVIORAL ECONOMICS INTERVENTION

Abstract Objective Despite approval of the first hybrid closed-loop (HCL) system for type 1 diabetes (T1D), many youth do not use the system effectively. This pilot study evaluated the impact of financial incentives for diabetes-related tasks to enhance use of the 670G HCL system, and the impact this had on glycemia. Methods At auto mode initiation, and for 16 weeks thereafter, participants received a flat rate for wearing and calibrating the sensor ($1/day), giving at least 3 meal boluses per day ($1/day), and uploading ($5/week). Weekly bonuses were given for maintaining at least 70% of the time in auto mode and bonuses increased for persistent auto mode use from a baseline reward of $3/week to a maximum of $13/week. If participants failed to maintain auto mode for the week, rewards were reset to baseline. Data from 17 participants (12 female) ages 15.9 ± 2.5 years (baseline HbA1c 8.6 ± 1.1%) were collected at 6, 12 and 16 weeks. After 16 weeks, reinforcers were withdrawn and a follow up assessment occurred at 24 weeks. Results During the reinforcement period, on average, youth gave at least 3 meal boluses per day and wore the sensor over 70% of the time. However, auto mode use waned. HbA1c levels decreased by 0.5% after 6 weeks, and this improvement was maintained at 12 and 16 weeks (p Conclusion In this pilot study of youth initiating the 670G HCL system, receiving compensation for diabetes-related tasks was associated with lower HbA1c levels, consistent mealtime boluses, and sustained CGM use. These results support the potential for improving outcomes in youth with T1D using financial rewards.