75-LB: Can Continuous Glucose Monitoring Be Utilized to Monitor Adherence to Time-Limited Eating in Adolescents with Obesity?

Background: One limitation to studying time limited eating (TLE) in adolescents is difficulty in reliably assessing adherence to fasting periods. Dietary recalls, which are currently used to monitor diet adherence, have been criticized due to potential error in reporting, omission bias and suboptimal compliance. Continuous glucose monitoring (CGM) may be a useful tool to overcome these barriers; however, it requires daily wear and understanding of expected glycemic excursions. The present study examines the feasibility of daily CGM use and its utility as a tool to monitor adherence to fasting periods in a diverse cohort of adolescents with obesity participating in a pilot study of 8-hour TLE. Methods: Twenty adolescents (mean age 16.0+1.3 years, 70% female, 55% Latinx, 75% public insurance) with BMI ≥ 95th percentile, were enrolled in a 12-week study and randomized to: (1) Group 1 (control schedule): 12-hour eating period + blinded CGM, (2) Group 2 (TLE schedule): 8-hour eating period + blinded CGM, or (3) Group 3: 8-hour eating period + CGM with real-time feedback. CGM wear time was calculated as the actual weekly wear time divided by the prescribed wear time. At weeks 0, 4 and 12, CGM data from 7 days of self-reported fasting periods were reviewed to evaluate any glycemic excursions >50 ng/dL. Results: Overall, the mean CGM wear time was 90% (35-100%) with no difference between intervention arms. During self-reported fasting periods, only 4 adolescents had excursions >50 ng/dL, one of whom was diagnosed with type 2 diabetes. The remaining 16 participants had no excursions >50 ng/dL during their fasting periods. Conclusions: These data suggest that CGM may be a feasible tool to monitor adherence to TLE and provide a more accurate assessment of true fasting periods with less opportunity for error and bias when compared to self-report. Larger studies are needed to validate these findings and further explore the use of CGM as a tool in obesity research in adolescents. Disclosure M. Naguib: None. M. I. Goran: None. J. Raymond: None. E. Hegedus: None. C. Wee: None. A. Vidmar: None.