1233-OR: Postmeal Glucose Patterns as Early Predictors of Gestational Diabetes

Introduction and Objective: Gestational Diabetes Mellitus (GDM) screening at 24-28 weeks limits early intervention. Emerging studies, such as GLAM, have evaluated early screening using Continuous Glucose Monitoring (CGM) and standard metrics (e.g., TA140) as biomarkers, showing promising results. We hypothesize that novel features derived from post-prandial (PP) glucose profiles can outperform standard CGM metrics and HbA1c in predicting GDM risk. Methods: We analyzed CGM and Oral Glucose Tolerance Test (OGTT) data from 936 participants across two multicenter studies (MAGIC, GLAM). A meal detection algorithm identified PP excursions from CGM data, extracting features including 1-hour glucose change (PP Delta-1h) and total glucose excursion (PP Glucose Excursion). Predictive performance of PP features was evaluated against OGTT outcomes using logistic regression and ROC-AUC analysis and compared to standard metrics like Time Above 140 mg/dL (TA140), mean glucose, glucose variability SD glucose, and HbA1c. Results: PP features showed superior GDM prediction. PP Delta-1h yielded a ROC-AUC of 0.78, a 10% relative improvement over TA140 (0.71) and 24% over HbA1c (0.63). Matching 85% sensitivity, a PP Delta-1h threshold 24 mg/dL achieved 53% specificity, reducing false positives by 18% compared to a TA140 threshold 0.9% (42% specificity). Conclusion: Early pregnancy post-meal CGM analysis offers superior GDM risk stratification. The PP Delta-1h marker identifies high-risk individuals, enabling earlier, more targeted preventative care. Disclaimer:Abbott Diabetes Care supported this study. MAGIC was funded by Medical Research Council ((MRC reference MR/T001828/1).The source of part of the data is the GLAM Study, but the analyses, content and conclusions presented herein are solely the responsibility of the authors and have not been reviewed or approved by the GLAM Study Leadership. Disclosure A.S. Mousavi: Employee; Current; Abbott Diabetes. E. Scott: Research Support; Ended; Abbott Diabetes. Speaker's Bureau; Ended; Ypsomed AG, Lilly. Advisory Panel; Ended; Abbott Diabetes. H. Murphy: Advisory Panel; Ended; Medtronic. Advisory Panel; Current; Ypsomed AG. Research Support; Ended; Dexcom, Inc. Research Support; Current; Abbott. Speaker's Bureau; Current; Dexcom, Inc., Ypsomed AG. Other - DDEA visiting researcher fellowship; Current; Novo Nordisk. N. Singh: Employee; Current; Abbott Diabetes. A. Bhattacharya: Employee; Current; Abbott Diabetes. T. Dunn: Employee; Current; Abbott Diabetes. T. Peng: Employee; Current; Abbott Diabetes. B. Olson: Employee; Current; Abbott Diabetes. G. Hayter: Employee; Current; Abbott Diabetes. Funding Medical Research Council (MRC reference MR/T001828/1); Abbott Diabetes Care