The Cambridge studies were randomized, controlled trials involving 17 children and adolescents conducted at the Wellcome Trust Clinical Research Facility at Addenbrooke's Hospital in Cambridge, United Kingdom over the course of 54 nights. Twelve subjects were used for the first study; 6 subjects were used for the second, and 9 for the third. Some 33 nights were on a closed-loop artificial pancreas system, while 21 nights were controlled (on standard therapy). During the closed-loop studies, continuous glucose measurements were fed into a computer program every 15 minutes, which calculated the insulin infusion rate; the insulin pump was adjusted manually by a research nurse. During control nights, the subject's standard insulin pump settings were applied.

Type 1 diabetes is an autoimmune disease in which the immune system attacks and kills off the cells in the pancreas that produce insulin, a hormone that enables people to convert food into energy. It affects 3 million American children, adolescents, and adults.

To manage their disease, people with type 1 diabetes need to measure their blood sugar multiple times throughout the day (typically by pricking a finger for a drop of blood), and pump insulin or inject themselves multiple times daily to keep blood sugar levels within a healthy range. That daily routine continues for life, because insulin administration does not cure diabetes.

Research has shown that good blood sugar control is a key factor in reducing the risk of the devastating long-term complications of the disease, such as blindness and kidney disease - but that the fear of low blood sugar emergencies often prevents many people from achieving tight control, and remains a constant concern for those who manage their diabetes well. The landmark Diabetes Control and Complications Trial (DCCT) showed that with intensive insulin therapy, excellent blood glucose control was obtained, but at the expense of a considerable increase in hypoglycemia.

Source: Juvenile Diabetes Research Foundation International