(P10-004-23) Dietary Self-Monitoring Adherence Is Associated With Increased Time in Recommended Glucose Range in Prediabetes and Moderately Controlled Type 2 Diabetes

Objectives: Clinical interventions for adults with prediabetes and type 2 diabetes (T2D) have increasingly used continuous glucose monitoring (CGM) to evaluate changes in glucose control via computational metrics such as the time in range (70-140 mg/dL; TIR). However, there is limited research analyzing TIR changes in dietary interventions and factors that impact TIR change. The main objective of this report is to evaluate the association of dietary self-monitoring adherence with time in range in a 6-month weight loss study.

Methods: The Personal Diet Study was a 6-month, single-center, randomized weight loss trial in prediabetes and moderately controlled T2D adults with overweight or obesity. All participants received behavioral weight loss counseling and self-monitored their dietary intake using a smartphone app. They wore an Abbott Freestyle Libre Pro blinded CGM for ≤2 weeks at baseline and 6-month assessments. Data across randomization groups were combined. We computed the change in two TIR metrics recommended by the 2022 International CGM Consensus Guidelines: overall TIR (all CGM readings; “All-TIR”) and daytime TIR (6am-midnight CGM readings; “Day-TIR”). We used linear regression to evaluate the association between dietary self-monitoring adherence, defined as % of days the user logged >0 calories into the study app, and change in the two TIR metrics.

Results: We analyzed baseline and 6-month CGM data from 66 participants (age 63±8 years, 62% female, 64% White, 20% African American, BMI 31.5±5.0 kg/m², HbA1c 5.8±0.5%). We observed non-significant improvements in All-TIR of 2.3% [95% CI: (-1.5,6.1)%, p=0.23] and Day-TIR of 2.9% [95% CI: (-0.7,6.5)%, p=0.12]. Linear regression models adjusting for baseline TIR, age, self-reported sex and race, BMI, and metformin use (yes/no) showed that higher dietary self-monitoring adherence was associated with increased All-TIR (p=0.02) and Day-TIR (p=0.03).

Conclusions: For individuals with prediabetes and moderately controlled T2D engaged in weight loss, higher dietary self-monitoring adherence may help to improve glucose control via increased time in the recommended glucose range.

Funding Sources: American Heart Association