1575-P: Wait-List-Design Pilot CGM-Behavioral Intervention for Youth with Type 1 Diabetes: Twelve-Month Primary Outcomes

Introduction and Objective: Despite being the standard of care for type 1 diabetes (T1D) management, many youth struggle with optimal continuous glucose monitor (CGM) use. ROUTE-T1D is a pilot, waitlist-design, three-session behavioral intervention for youth-caregiver dyads focused on CGM problem solving and positive communication. Methods: Participants included 60 youth ages 10-15 years with 75% CGM use (M age=12.9±1.7 yrs; 58% male, 42% female; 53% Black, 27% Hispanic/Latino/a/x, 12% another racially minoritized identity, 8% white; 72% public insurance; M T1D Duration=5.2±3.4 yrs; M A1c=10.6±2.0%; M CGM wear-time= 45±25%; M CGM TIR =30±16%) randomized to immediate (n=31) or delayed (i.e., waiting 6 months; n=29) intervention. To assess outcomes using both intervention groups, A1c, time-in-range (TIR), and CGM wear-time were analyzed at two combined timepoints: pretreatment: baseline (immediate group) and 6 months (delayed group), and post-treatment: 6 months (immediate group) and 12 months (delayed group). Longer term A1c outcomes (12 month) for the immediate group were also analyzed. Paired t-tests were used for all analyses. Results: A1c significantly decreased from pretreatment (10.5±2.2%) to post-treatment (10.0±2.1%, p=.028) in the combined sample. TIR significantly increased in both groups from pretreatment (31.3±15.7%) to post-treatment (37.1±15.7%, p=.022). CGM wear-time did not significantly change. The immediate group maintained a lower A1c at 12 months (9.9±2.1% at 6 months; 9.8±1.7% at 12 months). Conclusion: The intervention led to a significant and clinically meaningful reduction in A1c and an increase in TIR in the full waitlist-design sample, demonstrating positive effects on glycemic outcomes. Decreased A1c was sustained at 12 months in the immediate group. A larger multi-site study is warranted to examine intervention efficacy and future clinic implementation. Disclosure E. Straton: None. S. White: None. R. Longendyke: Advisory Panel; Ended; Sanofi. G. Maya: None. A. Perkins: None. S. Majidi: Advisory Panel; Current; Sanofi. M. Monaghan: Employee; Ended; National Institute of Diabetes and Digestive and Kidney Diseases. R. Streisand: None. Funding This work is supported by the National Institutes of Health (R01DK121316 and K26DK138330)