After globally adjusting the software parameters to a slower insulin absorption rate, the researchers conducted repeat experiments in the same participants. This time none of the slow-absorption participants experienced hypoglycemia significant enough to require intervention. Blood-sugar levels were only slightly higher in repeat experiments involving participants with fast insulin absorption, showing that the adjusted software parameters were effective for all study participants and may be adequate for everyone with type 1 diabetes. The elimination of episodes of hypoglycemia in repeat experiments involving the same participants affirmed that the initial mismatch between parameter settings and insulin absorption rate had been the cause of the hypoglycemia. All previous reported studies of artificial pancreas systems have included episodes of hypoglycemia, but this is the first study to confirm and address the cause of that hypoglycemia.

Later this spring the researchers will begin a follow-up study with a system using the revised settings and driven by an FDA-approved continuous glucose monitor. Those experiments will last more than 48 hours and include children as well as adults. The investigators also plan to compare the insulin/glucagon system with a version that uses only insulin. "The device we ultimately envision will be wearable and incorporate a glucose sensor inserted under the skin that communicates wirelessly with a pump about the size of a cell phone," says Russell, who is an instructor in Medicine at Harvard Medical School. "The pump would administer insulin and probably glucagon, and would contain a microchip that runs the control software."

Damiano, whose 11-year-old son was diagnosed with type 1 diabetes at the age of 1, adds, "A system like this would replace the need for people to constantly check their blood sugar and to make treatment decisions every few hours. It would need to be maintained but could take over the decision-making process, closely emulating a functioning pancreas. It wouldn't be a cure, but it has the potential to be the ultimate evolution of insulin therapy for type 1 diabetes." Damiano is an associate professor of Biomedical Engineering at Boston University.

SOURCE Boston University