Study results have revealed that pregnant women with type 1 diabetes mellitus (T1DM) treated with hybrid closed-loop therapy, known as an ‘artificial pancreas’, showed significantly improved glycaemic control than standard insulin therapy.
The randomised controlled trial, published in The New England Journal of Medicine on 5 October 2023, tested the efficacy of automated insulin delivery across nine sites in the UK.
The study included 124 pregnant women aged 18–45 years, who had been diagnosed with T1DM for at least 12 months and were in their first 16 weeks of pregnancy.
Participants were randomly assigned to receive either the automated hybrid closed-loop therapy (n=61) or to continue their standard intensive insulin therapy via traditional insulin pumps or multiple daily injection methods (n=63). Both groups received continuous glucose monitoring.
Glycaemic control was measured by comparing the percentage of time in pregnancy-specific target glucose range (63–140mg/dL) from 16 weeks gestation (baseline) until delivery.
Researchers found that women in the hybrid closed-loop therapy group were in target range at an average of 68.2% of the time (from 47.8%), compared to 55.6% in the standard therapy group (from 44.5%) — 10.5% mean adjusted difference; 95% confidence interval; P<0.001.
Women in the hybrid closed-loop group also spent less time at hyperglycaemic state, gained less maternal weight and had fewer hypertensive complications compared to the standard therapy group.
No differences were observed in the number of preterm births, birth weight, neonatal complications, or admissions to the neonatal intensive care unit.
Lead author Helen Murphy, professor of medicine (diabetes and antenatal care) at the University of East Anglia, said: “For a long time, there has been limited progress in improving blood sugars for women with T1DM, so we’re really excited that our study offers a new option to help pregnant women manage their diabetes.”
In January 2023, the National Institute for Health and Care Excellence (NICE) recommended the use of hybrid closed-loop systems for T1DM in draft guidance, estimating that around 105,000 people in England and Wales could be offered the technology for managing blood glucose levels.
Commenting on the study, Faye Riley, research communications manager at Diabetes UK, said: “The draft NICE recommendations for hybrid closed-loop technology rightly acknowledge its benefits for pregnant women with T1DM, prioritising them for access, and this study reinforces the importance of making the technology available to them.
“With the final NICE guidance for England and Wales expected by the end of this year, it is vital that hybrid closed loop technology is backed by national funding to ensure it can be offered fairly to all pregnant women with type 1 diabetes,” she added.
Eleanor Scott, co-author and professor of medicine (diabetes and maternal health) at Leeds Teaching Hospitals NHS Trust, commented: “Maybe five years ago, people would come with blood sugar books, [having] written down what their blood sugar readings were five to nine times a day.
“With this technology, everything is hosted on smartphones and all the information about glucose and insulin is gathered through an app.
“Patients can look at it on their phones and see exactly what your glucose is doing and how much time in range you’ve got when insulin is being given. This is game-changing for women,” she added.