Article Impact Level: HIGH Data Quality: STRONG Summary of Diabetes Care, dc241848. https://doi.org/10.2337/dc24-1848 Dr. Ravi Retnakaran et al.
Points
- The study assessed the 1-hour (1-h) oral glucose tolerance test (OGTT) as a more effective predictor of postpartum dysglycemia (prediabetes/diabetes) compared to the traditional 2-hour (2-h) OGTT.
- The study followed 369 postpartum women, including those with normoglycemia and gestational diabetes (GDM), who underwent 75g OGTTs at 3 months, 1 year, 3 years, and 5 years postpartum.
- At 3 months postpartum, the 1-h glucose test identified all but 10 of the 70 women diagnosed with dysglycemia by the 2-h OGTT while also detecting an additional 96 cases missed by the 2-h test.
- Regression analysis showed that 1-h glucose was the strongest predictor of future dysglycemia, with a change in concordance index (CCI) of 16.1%, outperforming the 2-h glucose (CCI of 14.9%).
- The findings suggest that the 1-h OGTT could serve as a more practical and efficient screening tool for postpartum dysglycemia, potentially improving early detection and management of glucose disorders in women after pregnancy.
Summary
This study aimed to evaluate the efficacy of the 1-hour (1-h) oral glucose tolerance test (OGTT) compared to the 2-hour (2-h) OGTT for predicting dysglycemia (prediabetes/diabetes) in postpartum women. The study involved 369 women with varying glucose tolerance during pregnancy, including those with normoglycemia and gestational diabetes (GDM). These women underwent a series of 75g OGTTs at 3 months, 1 year, 3 years, and 5 years postpartum. The glucose measurements from the 3-month OGTT were analyzed to assess their ability to predict future dysglycemia using Cox proportional hazard regression models, focusing on the change in concordance index (CCI).
The results showed that at 3 months postpartum, 1-h glucose identified all but 10 of the 70 women diagnosed with dysglycemia based on the 2-h OGTT. Additionally, 1-h glucose diagnosed 96 women whom the 2-h OGTT missed. The cumulative incidence of dysglycemia increased progressively over 5 years according to the tertile of 1-h glucose (P < 0.0001). In regression analysis, 1-h glucose emerged as the strongest predictor of dysglycemia with a change in CCI of 16.1%, followed by 2-h glucose with a change in CCI of 14.9%. In women with GDM, 1-h glucose again proved to be the strongest predictor of dysglycemia (13.0%), just slightly ahead of the 2-h glucose measure (12.8%).
These findings suggest that the 1-h OGTT may be a more convenient and effective tool for identifying women at risk of dysglycemia postpartum. It could potentially improve reclassification rates and address the challenges associated with the more cumbersome 2-h OGTT. This could help increase postpartum screening rates and aid in the timely management of glucose-related disorders in women after pregnancy.
Link to the article: https://diabetesjournals.org/care/article-abstract/doi/10.2337/dc24-1848/157936/One-Hour-Oral-Glucose-Tolerance-Test-for-the/
References Retnakaran, R., Ye, C., Kramer, C. K., Hanley, A. J., Connelly, P. W., Sermer, M., & Zinman, B. (2025). One-hour oral glucose tolerance test for the postpartum reclassification of women with hyperglycemia in pregnancy. Diabetes Care, dc241848. https://doi.org/10.2337/dc24-1848
