Adults with type 1 diabetes in a newly published study showed improvements in overnight blood sugar control when an experimental computer-assisted device was used, with fewer episodes of levels dropping to dangerously low levels.
For decades, researchers have searched unsuccessfully for a way to automatically coordinate insulin delivery with real-time changes in glucose to maintain optimal blood sugar levels with minimal effort.
Technological advances have led to commercial devices that continuously monitor blood sugar, as well as insulin pumps.
Researchers are now attempting to tie the two together using sophisticated computer software.
In studies in children with type 1 diabetes, the experimental devices proved to be better than conventional insulin pump delivery for maintaining optimal blood sugar control during the night.
The new study, published today in BMJ Online First, is among the first to show the same thing in adults.
Overnight Glucose Control
“In children and young adults with type 1 diabetes, nighttime hypoglycemia represents the greatest risk for death,” American Diabetes Association past president Larry C. Deeb, MD, tells WebMD.
It is also among the biggest dangers for adult patients.
The new research compared an experimental computer algorithm, which coordinated glucose monitoring and delivery to traditional insulin pump delivery in 24 adults with type 1 diabetes who had used an insulin pump for at least three months before enrollment.
In one scenario, 12 patients who ate a moderate-sized meal early in the evening were assigned to either the experimental artificial pancreas or conventional insulin pump therapy during overnight hours for two nights, separated by a period of one to three weeks.
The design was similar to a second scenario, except that the 12 remaining patients ate a heavier meal later in the evening and the meal included wine.
“The point of this was to test the devices in different real-world situations,” says study researcher Roman Hovorka of the University of Cambridge Metabolic Research Laboratories.
In both scenarios, use of the computer-assisted model resulted in better overnight glucose control compared to traditional insulin pump delivery. The time spent with blood sugar levels in the target range increased by up to about 28% with the closed-loop insulin delivery.
Roadblocks to Artificial Pancreas
Deeb says the research in children and adults provide strong evidence that a fully automated, practical system for coordinating blood sugar monitoring and insulin delivery is possible and will improve nighttime blood sugar control.
But in the studies reported so far, nurses manually transmitted data from the glucose monitors to the computer and transmitted insulin injection recommendations from the computer to the insulin pump to ensure that patients got appropriate doses of insulin.
Hovorka says the technology exists to make the process fully automatic, but the researchers have not received approval to test the technology.
Technological challenges to a fully automated artificial pancreas also remain, and the path to approval is far from certain, Spyros G. Mezitis, MD, of Lenox Hill Hospital in New York City, tells WebMD.
‘The FDA is likely to be very cautious about approving these devices,” he says. “The investigators will have to prove that they are safe.”
Deeb says he would like to see a first-generation artificial pancreas approved for nighttime use within the next year.
“FDA is being abundantly cautious and that is understandable,” he says. “But my feeling is that if it is not yet time to approve them, it certainly will be soon.”