1199-P: Timing of Postprandial Peak CGM Glucose in Gestational Diabetes

Abstract

Background: Current guideline recommendations for management of gestational diabetes mellitus (GDM) recommend capillary testing of blood glucose levels fasting and one-two hours postprandial. Use of intermittently-scanned continuous glucose monitors (isCGM) during pregnancy in women with GDM has the potential to improve fetal outcomes, however there are limited recommendations for their use. Optimal timing of postprandial testing is unknown. Methods: Women with GDM diagnosed after 24 weeks gestation were recruited and randomized to adjunctive use of isCGM versus capillary testing with blinded CGM. In this subanalysis of 8 participants, timing of peak CGM glucose value is compared to recommended 1-hour postprandial capillary value. Food logs and/or meter data from the first two weeks of participation were used for analysis. Results: A total of 265 meals were analyzed. Gestational age at analysis was 29±1.2 weeks. One participant was treated with insulin. Three participants used blinded CGM; 5 used isCGM. Mean peak CGM glucose was 100±11 mg/dL. Mean time to peak was 96±14 minutes. Seventy-four percent of peak glucoses were after one hour. Conclusions: Current recommendations for glucose monitoring may need to be adapted to use of new technology with isCGM. Our data found that if a user only scanned at one hour postprandial, they could miss the peak glucose for the majority of meals. Repeat scanning or retrospective review of isCGM data may be required to determine the timing of a user’s postprandial peaks in relation to glycemic goals. Factors like the lag in CGM glucose compared to capillary testing and meal content should be considered with isCGM use. Disclosure G.O'malley: Research Support; Dexcom, Inc., Abbott Diabetes, Tandem Diabetes Care, Inc., Omnipod, Eli Lilly and Company. M.Kononenko: None. S.J.Ogyaadu: None. C.Levister: Research Support; Dexcom, Inc., Tandem Diabetes Care, Inc., Abbott Diabetes. E.Ellis: None. D.Arumugam: None. L.Vieira: None. C.J.Levy: Advisory Panel; Dexcom, Inc., Research Support; Abbott Diabetes, Dexcom, Inc., Insulet Corporation, Tandem Diabetes Care, Inc., T1D Exchange. Funding Abbott Diabetes Care