Artificial pancreas for adults with type 1 diabetes

15th April 2011 - Research funded by Diabetes UK has for the first time successfully demonstrated the potential of an 'artificial pancreas' in preventing night-time hypoglycaemia in adults with type 1 diabetes.

Type 1 diabetes develops when insulin-producing cells in the pancreas are destroyed. It's the least common of the two main types of diabetes and affects around 350,000 people in the UK.  Type 1 diabetes cannot be prevented; it is not known why it develops and it is not connected with being overweight.

Hypoglycaemia (or a 'hypo') occurs when the level of glucose in the blood falls too low. If left untreated the person having a hypo can eventually become unconscious after experiencing warning signs as the body tries to raise the blood glucose level. These unpleasant signs often include feeling shaky, sweating, tingling in the lips, heart pounding and irritability. In extreme cases, hypoglycaemia can lead to coma and brain damage and can sometimes prove fatal.

What's different about the 'artificial pancreas', or closed-loop insulin delivery system, is that it automatically manages a person's diabetes and takes minute-by-minute glucose readings. The device regulates blood glucose levels by releasing insulin when alerted to high levels of glucose and withholding it when levels are low.

Currently, people with type 1 diabetes have to either inject insulin several times a day or wear an insulin pump which releases pre-set levels of the hormone via a cannula inserted under the skin.

Eating and sleeping

University of Cambridge researcher Dr Roman Hovorka led two studies to evaluate the performance of the artificial pancreas in 10 men and 14 women, aged 18 to 65, who had used an insulin pump for at least three months.

The studies were carried out at the Wellcome Trust clinical research facility at Addenbrooke’s Hospital, Cambridge, between February and December 2009.

The first study monitored 12 participants overnight who had consumed a medium-sized meal (60 g carbohydrate)at home at 7pm. In the second study, the other 12 participants were monitored overnight after eating out and consuming a larger meal (100 g carbohydrate) accompanied by alcohol at 8.30pm.

Conclusions

The studies showed a 22% improvement in the time participants kept their blood glucose levels in a safe range, halving the time they spent with low blood glucose levels and reducing the risk of both short term and long term complications.

The study authors said the trials suggest that closed loop delivery of insulin may improve overnight control of glucose levels and reduce the risk of nocturnal hypoglycaemia in adults with type 1 diabetes.

Dr Roman Hovorka said in a press release: "Hypoglycaemia remains a major challenge, especially during the night, so it's encouraging to see such promising results from our trial using commercially available devices.