The study conducted with children and adolescents with type 1 diabetes aimed to measure the effectiveness of three strategies in reducing nocturnal hypoglycemia. Taking place over multiple nights at a diabetes camp last summer, the trial compared conventional insulin pump therapy with two configurations of the external artificial pancreas being developed at the IRCM: the single-hormone (insulin alone) artificial pancreas and the dual-hormone (insulin and glucagon) artificial pancreas.
“The dual-hormone artificial pancreas has the potential to reduce hypoglycemia more than the other strategies, but the relative benefits provided by glucagon had not yet been assessed in outpatient settings,” says Dr. Rabasa-Lhoret, endocrinologist and clinical researcher at the IRCM. “Demonstrating the effectiveness of the artificial pancreas among children in an uncontrolled environment is an important step in making this technology available to the general public in the near future.”
Patients with type 1 diabetes must maintain their blood glucose levels within a target range in order to prevent serious long-term complications related to high glucose levels and reduce the risk of hypoglycemia (very low blood glucose that can lead to confusion, disorientation and, if severe, loss of consciousness, coma and seizure). Results from the study showed the dual-hormone artificial pancreas increased the percentage of time spent within this recommended target range.
“During our study, we also found that no participant using the dual-hormone system experienced a nocturnal hypoglycaemia event requiring treatment,” explains Ahmad Haidar, PhD, engineer and postdoctoral fellow at the IRCM. “This is significant when considering that hypoglycaemic events occurred on 16 per cent of nights with conventional pump therapy, and 4 per cent of nights with the single-hormone artificial pancreas.”
“Most hypoglycaemia seizures in children and adolescents happen at night-time, and fear of these episodes is a major source of stress and anxiety for families and caregivers of children with type 1 diabetes,” mentions Dr. Legault, paediatric endocrinologist at the Montreal Children's Hospital. “This represents a major barrier to efforts to intensify treatment in order to reach glycemic targets.”
“The dual-hormone artificial pancreas could improve nocturnal glucose control and reduce hypoglycaemia, potentially improving quality of life, but it also requires an extra catheter and additional drug manipulation,” adds Dr. Rabasa-Lhoret. “Longer and larger outpatient studies are now needed to assess whether it is justifiable to add glucagon to the artificial pancreas. To predict future adherence to dual-hormone therapy, we also need to assess, from patients' perspectives, whether the clinical benefits outweigh the increased cost and complexity.”
Type 1 diabetes is one of the most common chronic diseases in young people and, each year, its incidence is increasing by two to five per cent worldwide. According to the Canadian Diabetes Association, more than 10 million Canadians are living with diabetes or prediabetes today. About five to 10 per cent of them have type 1 diabetes.
About the external artificial pancreas
An emerging technology to treat type 1 diabetes, the external artificial pancreas is an automated system that simulates the normal pancreas by continuously adapting insulin delivery based on changes in glucose levels. Two configurations exist: the single-hormone artificial pancreas that delivers insulin alone and the dual-hormone artificial pancreas that delivers both insulin and glucagon. While insulin lowers blood glucose levels, glucagon has the opposite effect and raises glucose levels. Infusion pumps and continuous glucose sensors (CGM) are already commercially-available. IRCM researchers are developing an intelligent dosing algorithm to act as the brain of the artificial pancreas system. The algorithm, which could eventually be integrated as software into a smart phone, receives data from the CGM, calculates the required insulin (and glucagon, if needed) and wirelessly controls the pump to automatically administer the proper doses without intervention by the patient. The technology should be available commercially within the next five to seven years, with early generations focusing on overnight glucose control. For more information, please visit www.ircm.qc.ca/pancreas.
About the study
Co-supervised by Drs. Rémi Rabasa-Lhoret and Laurent Legault, the randomised clinical trial was conducted in July and August 2014 at Camp Carowanis, a summer camp managed by the Diabetic Children's Foundation. A total of 33 children participated in the study, which took place over six weeks and was divided into three two-week sessions. Participants were aged 9 to 17 years, on an insulin pump for at least three months, and diagnosed with type 1 diabetes for at least one year. Each child participated in the research project for nine nights, during which each system was tested over a three-night period. Each observation period began at 10 p.m. and ended at 7 a.m. the following morning.
The research project was funded by the Canadian Diabetes Association, Dr. Rabasa-Lhoret's J.A. De Sève Chair in clinical research, and Dr. Haidar's Banting postdoctoral fellowship. The study's authors include Laurence Matteau-Pelletier, Virginie Messier and Maryse Dallaire from the IRCM, as well as Martin Ladouceur from CRCHUM (research centre from the Centre hospitalier de l'Université de Montréal). For more information on the study, please refer to the article summary published by The Lancet Diabetes & Endocrinology: http://www.thelancet.com/journals/landie/article/PIIS2213-8587(15)00141-2/abstract.