663-P: Dynamic Real-Time Relationships among Glucose and Cognitive Performance in Diverse Adults with T1D

Introduction: Blood glucose (BG) regulation is linked to cognitive performance among people with diabetes. Most studies are cross-sectional and limited to adults with T2D. Pairing continuous glucose monitoring (CGM) with ambulatory cognitive tests, we examined real-time bidirectional associations between BG and cognition in everyday life among adults with T1D. Methods: Participants wore a blinded CGM for 10-14 days and completed ambulatory cognitive tests 5-6 times daily. Using dynamic structural equation modeling, we evaluated within-person bidirectional relationships between BG and cognition over sequential 3-hr periods. BG metrics included mean BG, time in range (TIR; 70-180 mg/dL), % time in low (50-69 mg/dL), high (181-250 mg/dL) and very high BG (>250 mg/dL), and coefficient of variation (CV). Cognitive variables included processing speed and sustained attention. Results: Among 182 adults with T1D (40±14 yrs, 46% male, 41% Latino, 29% White, 15% Black), greater mean BG (beta=0.03), lower TIR (beta=-0.03), and more time in high (beta=0.03) and very high BG (beta=0.03) predicted slower processing speed 3 hrs later (ps