Artificial pancreas a step nearer

Scientists in Cambridge have made a significant step towards developing an ‘artificial pancreas’ system for managing type 1 diabetes in children.

Using an artificial pancreas system overnight can significantly reduce the risk of hypoglycemia, when blood glucose levels drop dangerously low, while sleeping.

These so-called ‘hypos’ are a major concern for children and adults with type 1 diabetes.

The artificial pancreas system combines a continuous glucose monitor and an insulin pump, both already on the market, and uses a new algorithm to calculate the appropriate amount of insulin to deliver based on the real-time glucose readings.

As well as obviating the need for multiple daily finger-prick tests and insulin injections, the artificial pancreas offers better control of blood glucose levels overnight.

In a study, 17 children and teenagers aged between five and 18 with type 1 diabetes were studied during 54 nights at Addenbrooke’s Hospital.

The Cambridge team measured how well the artificial pancreas system controlled glucose levels compared with the children’s regular continuous subcutaneous insulin infusion (CSII) pump, which delivers insulin at preselected rates.

The study included nights when the children went to bed after eating a large evening meal or having done early evening exercise.

Both are challenging to manage: a large evening meal because it can lead to so-called ‘insulin stacking’ and consequently a potentially dangerous drop in blood glucose-levels later in the night; and late afternoon or early evening exercise because it increases the body’s need for glucose in the early morning and can therefore increase the risk of night-time hypoglycaemia.

The pooled results showed the artificial pancreas kept blood glucose levels in the normal range for 60 per cent of the time, compared with 40 per cent for the CSII.

The artificial pancreas halved the time that blood glucose levels fell below 3.9mmol/l – the level considered as mild hypoglycaemia.

It also prevented blood glucose falling below 3.0mmol/l, which is defined as significant hypoglycaemia, compared with nine hypoglycaemia events in the control studies.

Dr Roman Hovorka, of the Institute of Metabolic Science at Cambridge University, said: ‘Our results show that commercially available devices, when coupled with the algorithm we developed, can improve glucose control in children and significantly reduce the risk of hypos overnight.

‘This is the first randomised study showing the potential benefit of the artificial pancreas system overnight using commercially available sensors and pumps.

‘Our study provides a stepping stone for testing the system at home.’