Pregnant women with type 1 diabetes who used a hybrid closed loop automated insulin delivery (AID) system averaged more than three additional hours per day in their recommended glucose range than those who managed their diabetes with insulin injections or non-automated pump systems, a study presented at the 85th Scientific Sessions of the American Association (ADA) in Chicago demonstrated.
For pregnant women with type 1 diabetes, a target range of 63-140 mg/dL is recommended for maternal and fetal health but staying in that range can be challenging during gestation. Hyperglycemia during pregnancy increases the risk of miscarriage, preterm birth, birth defects, neonatal hypoglycemia, large for gestational age infants and respiratory distress in the infant. For the mother, it increases the risk of preeclampsia and caesarean delivery.
The study used the Tandem t:slim X2 insulin pump with Control-IQ Technology algorithm to adjust insulin delivery based on real-time glucose reading from a Dexcom G6 continuous glucose monitor (CGM) for the hybrid closed loop (HCL) system. The Control-IQ AID is available for use, but not U.S. FDA approved for use in pregnancy.
The multicenter, open-label trial enrolled 91 women with type 1 diabetes in early pregnancy and followed them for the remainder of the pregnancy. All the women had early pregnancy A1C levels of 6.2% to 10%. The women received care at 14 sites in Canada and Australia.
Researchers randomized participants to start HCL therapy by 16 weeks gestation or to continue with standard insulin injections or an insulin pump that was not automated, along with CGM, throughout their pregnancies. Participants were advised to use the sleep activity range, the lowest target range, throughout the day and night.
On average, the women who used the HCL system spent three additional hours or 12.5% more time in the pregnancy target glucose range than women in the other two groups. In addition, women in the HCL group had 11.5% less time above the target range (95% CI 8.3,14.5) and non-significantly less time below range, indicating more consistent management of glucose levels overall.
“Managing glucose levels during pregnancy with type 1 diabetes is of critical importance for optimal health in both mother and child,” said Lois Donovan, clinical professor at the University of Calgary AB Canada in the Cumming School of Medicine, department of medicine, division of endocrinology and metabolism, department of obstetrics and gynecology and lead presenter of the study. “Our results reflect the importance of evolving automated insulin delivery to support those living with type 1 diabetes when they are pregnant or preparing for pregnancy.”
Beyond use in HCL systems for type 1 and insulin-using type 2 diabetes, Dexcom hopes to obtain FDA approval for its CGMs in gestational diabetes. Research in that area, Dexcom President Jake Leach told BioWorld, shows that the feedback from CGMs reduces preterm birth and miscarriage as well as maternal hypertension.
