871-P: Baseline Time-in-Range Association with Glycemic Improvement in Adults with Type 1 Diabetes (T1D)

Abstract

The DIAMOND study demonstrated real-time continuous glucose monitors (CGM) improve glycemic control for adults with T1D using multiple daily injections; subsequent analysis showed greatest benefit in participants with higher baseline A1C. This analysis assesses the relationship between baseline time in range (TIR) and change in TIR during the study with CGM or self-monitoring of blood glucose (SMBG). Baseline TIR was divided into three categories: <40% (9.6 h/d), <50% (12 h/d), and <60% (14.4 h/d). Of 153 participants, mean A1C was 8.6±0.6% and the mean TIR was 46±12% (10.9±2.9 h/d) at baseline. Mean increase in TIR was greater among CGM users versus SMBG users for all three baseline TIR categories (18 min/d for baseline TIR <40%, 90 min/d for baseline TIR <50%, 88 min/d for baseline TIR <60%). A greater percentage of participants using CGM had >4 h/d increase in TIR across all baseline TIR groups, and >2 h/d increase in TIR in most baseline TIR groups, although a few were not significant due to small sample size (Figure). The most noticeable difference occurred for participants with a baseline TIR <50%, with 29% of CGM users increasing TIR by >4 h/d compared with no SMBG users (P=0.004). Similar trends were found for improvement in mean glucose and time spent in hyper- and hypoglycemic ranges. Overall, results suggest greater improvement in glycemic control for CGM users than for SMBG users across all baseline TIR groups. Disclosure P. Calhoun: Stock/Shareholder; Self; Dexcom, Inc. D.A. Price: Employee; Self; Dexcom, Inc. R. Beck: None. Funding Dexcom, Inc.