The Artificial Pancreas Study - Diabetes

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1 Winter 2008/9 The Artificial Pancreas (AP) studies are now well into the second year. In the past eighteen months we have completed a programme of three studies using our AP setup. STUDY 1 (The Pilot Study) As you may remember, the first study started in April 2007 when we recruited twelve children from the Diabetes Clinic in Addenbrooke's. In this study we compared overnight glucose control on standard pump therapy against glucose control using the Artificial Pancreas. The results from this study were very encouraging. Using the AP system, we managed to increase the time spent in normal glucose range (between 3.9 and 8mmol/l) more than twofold from 29% to 67%, and reduced the time spent in high glucose range (above 8mmol/l) from 47% to 32%. We also eliminated time spent in hypo range (below 3.3mmol/l) from 14% to 0% and reduced time spent in mild hypo range (from 3.4 to 3.9mmol/l) from 10% down to just 1% (see the pie charts below). Standard Pump Therapy Artificial Pancreas 1% 0% Key 8 mmol/l or above mmol/l mmol/l mmol/l

2 STUDY 2 (The Meal Study) In the second study we recruited six volunteers who had completed Study 1 and tested the Artificial Pancreas under more challenging conditions. Each subject came again for two overnight visits. On one visit they were offered a large meal of rapidly absorbed carbohydrates and on the other visit a large meal of slowly absorbed carbohydrates. The meal size varied from 100g-160g CHO and was accompanied by a prandial insulin bolus. The meal was served at 6:00pm and the AP was started at 6:30pm. Once again the results were very encouraging. Glucose values were similar to those obtained in the first study, confirming that glucose control after large meals can be safely controlled by the Artificial Pancreas. STUDY 3 (The Exercise Study) In this third study, which we have just completed, we tested the AP system under exercise conditions. For this study we recruited nine volunteers, aged between 10 and 18 years, who were subjected to a moderate exercise challenge. The volunteers completed two 20 minute sessions of walking/running on a treadmill in the early evening. Prior to this, subjects were only allowed one small snack at 4:00pm in the afternoon before the exercise and did not have any further food until breakfast time the following morning. The AP system coped extremely well with the effects of exercise, but the precise results are still being collated.

3 Future Studies We hope to start another in hospital study early in We will be testing a fully automated Artificial Pancreas for delivering insulin overnight in twelve children. This study will be a stepping stone towards testing of a fully automated closed-loop insulin delivery system in the home setting towards the middle of The preparations for the home studies are now in full swing. Taking part in a study will require a visit to the Paediatric Diabetes Clinic to assess patient eligibility and to attend training sessions on the use of the continuous glucose sensor and the insulin infusion pump devices that will be used in this particular study. The study will take place within the home setting where we will provide overnight supervision with a nurse until the children and parents feel confident with working the system. A total of twelve children and adolescents will be recruited from the Diabetes Clinic in the Department of Paediatrics, Addenbrooke s Hospital, and subjects from other clinics from the East Anglia region may also be eligible. Each volunteer will spend one month using the AP system and we will compare how well they do on this compared to another one month period where they will be using the pump and sensor only. Other News The Artificial Pancreas group is growing! We now have another full time nurse, Julie Harris, who will be working alongside Dr Mark Evans, the Clinical Principal Investigator, on the adult AP studies. Dr Daniela Elleri, Research Fellow, has been with the group for almost a year. Daniela is organising and supporting the clinical studies. Dr Helen Murphy is the Principle Investigator for pregnancy studies. Marianna Nodale is helping with data analysis. Linda Kristensen is a visiting student from Biomedical Engineering, Aalborg, University of Denmark; she will spend 6 months with us as part of her Masters Degree. Anne Mette Larsen from Denmark is now working as Research Assistant and is involved in the testing and evaluation of the Artificial Pancreas prototypes. Josephine Hayes has joined the group as Project Co-ordinator. We are particularly grateful to Dr Vijith Puthi and Alison Sadler from Peterborough and Stamford NHS Trust for all their help in recruiting children from the Diabetes clinic at Peterborough, and to Dr Nandu Thalange and Holly Roper for organising and recruiting children into the study from Norfolk and Norwich Hospital. Special thanks to Claire Pesterfield and Angie Youngs in the Weston Clinic for their continued help and support with the paediatric studies, and to Angie Watts and her team in the Department of Paediatrics for organising the blood samples both before and after the studies. Once again our thanks go to all the parents and children who have made this research possible, and some of whom are pictured below.

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5 Completion of the first three paediatric studies. Preparation for testing of the fully automated closed-loop system in the home setting. Preparation of studies to evaluate the Artificial Pancreas in adults with Type 1 Diabetes with funding from Diabetes UK. These studies will be very similar to the studies we have done in children. The preparations are also underway for testing the Artificial Pancreas in pregnant women with type 1 diabetes early next year. This study has also been funded by Diabetes UK. Thanks to John Davis who heads the support group INPUT, we were delighted to host a focus meeting on the Artificial Pancreas in June Twelve families from the South of England were invited to spend an afternoon in the paediatric clinic at Addenbrooke s. The equipment for the home study was displayed and demonstrated. Discussions were held with parents and children, who were asked to complete a questionnaire afterwards regarding use of an Artificial Pancreas in the home setting. We took several pictures on the day of the meeting, some of which can be seen below. The report from the focus meeting can be viewed at

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