The Performance of an Artificial Pancreas at Home in People With Type 1 Diabetes

• Continuous glucose monitoring (CGM) time spent in target glycaemic range (4.0-8.0 mmol/L) overnight (0000h - 0800h) during the ambulatory phase (Phase 2) of the study. [ Time Frame: Participants will be monitored overnight during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Continuous glucose monitoring (CGM) time spent in target glycaemic range (4.0-8.0 mmol/L) from 2000h-0800h in clinical trial centre (phase 1 of the study). [ Time Frame: Participants will be monitored in clinical trial centre (phase 1 of the study), an expected average of 12 hours. ]
  

• CGM time and area under the curve (AUC) spent above target range (>8.0 mmol/L). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• CGM time and area under the curve (AUC) spent above target range (>8.0 mmol/L). [ Time Frame: Participants will be monitored overnight (0000h - 0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• CGM time spent in hypoglycaemic range (<4.0 mmol/L and <3.0 mmol/L) and number of episodes of symptomatic hypoglycaemia (indicated by glucose sensor and confirmed by meter glucose). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• CGM time spent in hypoglycaemic range (<4.0 mmol/L and <3.0 mmol/L) and number of episodes of symptomatic hypoglycaemia (indicated by glucose sensor and confirmed by meter glucose). [ Time Frame: Participants will be monitored overnight (0000h - 0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• CGM measures of glycaemic variability (standard deviation and margin of error). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• CGM measures of glycaemic variability (standard deviation and margin of error). [ Time Frame: Participants will be monitored overnight (0000h - 0800h) the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Number of episodes of blood ketone-positive hyperglycaemia (blood glucose > 15 mmol/L indicated by glucose sensor and confirmed by meter glucose AND blood ketones greater than or equal to 0.6 mmol/L). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• Number of episodes of blood ketone-positive hyperglycaemia (blood glucose > 15 mmol/L indicated by glucose sensor and confirmed by meter glucose AND blood ketones greater than or equal to 0.6 mmol/L). [ Time Frame: Participants will be monitored overnight (0000h - 0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Yellow Springs Instrument (YSI) glucose measurements in target range (4.0-8.0 mmol/L). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• YSI glucose measurements in hypoglycaemic range (<4.0 mmol/L and <3.0 mmol/L). [ Time Frame: Participants will be monitored from 2000h-0800h phase 1 of the study, an expected average of12 hours. ]
  
• YSI glycaemic variability (standard deviation). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• CGM time in glucose target range (4.0-8.0 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) during the phase 1 of the study, an expected average of 16 hours. ]
  
• CGM time in glucose target range (4.0-8.0 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h during the ambulatory phase (Phase 2) of the study, an expected average of 16 hours each day for 4 days (Day 2-5 of phase 2). ]
  
• CGM time and area under the curve (AUC) spent above target range (>8.0 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) during the phase 1 of the study, an expected average of 16 hours. ]
  
• CGM time and area under the curve (AUC) spent above target range (>8.0 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) during the ambulatory phase (Phase 2) of the study, an expected average of 16 hours each day for 4 days (Day 2-5 of phase 2) ]
  
• CGM time spent in hypoglycaemic range (<4.0 mmol/L and <3.0 mmol/L) and number of episodes of symptomatic hypoglycaemia (indicated by glucose sensor and confirmed by meter glucose). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) during the phase 1 of the study, an expected average of 16 hours. ]
  
• CGM time spent in hypoglycaemic range (<4.0 mmol/L and <3.0 mmol/L) and number of episodes of symptomatic hypoglycaemia (indicated by glucose sensor and confirmed by meter glucose). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) the ambulatory phase (Phase 2) of the study, an expected average of 16 hours each day for 4 days (Day 2-5 of phase 2) ]
  
• Number of episodes of blood ketone-positive hyperglycaemia (blood glucose > 15 mmol/L indicated by glucose sensor and confirmed by meter glucose AND blood ketones greater than or equal to 0.6 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) the phase 1 of the study, an expected average of 16 hours. ]
  
• Number of episodes of blood ketone-positive hyperglycaemia (blood glucose > 15 mmol/L indicated by glucose sensor and confirmed by meter glucose AND blood ketones greater than or equal to 0.6 mmol/L). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) the ambulatory phase (Phase 2) of the study, an expected average of 16 hours each day for 4 days (Day 2-5 of phase 2) ]
  
• Total insulin delivered (based on pump data) [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• Total insulin delivered (based on pump data). [ Time Frame: Participants will be monitored overnight (0000h - 0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Rates and number of changes in the rate of insulin infusion (based on pump data). [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• Rates and number of changes in the rate of insulin infusion (based on pump data). [ Time Frame: Participants will be monitored overnight (0000h-0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Closed loop exits (with root cause identified) based on the monitoring by the investigator in real time from a co-located station. [ Time Frame: Participants will be monitored from 2000h-0800h in phase 1 of the study, an expected average of 12 hours. ]
  
• Closed loop exits (with root cause identified) based on the remote monitoring by the investigator. [ Time Frame: Participants will be monitored overnight (0000h-0800h) during the ambulatory phase (Phase 2) of the study, an expected average of 8 hours each night for 4 nights (Day 1-4 of phase 2). ]
  
• Total basal and total bolus insulin delivered (based on pump data) [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) the phase 1 of the study, an expected average of 16 hours. ]
  
• Total basal and total bolus insulin delivered (based on pump data). [ Time Frame: Participants will be monitored in daytime (0800h - 0000h) the ambulatory phase (Phase 2) of the study, an expected average of 16 hours each day for 4 days (Day 2-5 of phase 2) ]
  
• Urinary cortisol and catecholamines on 12-hour urine collection. [ Time Frame: Urine sample will be collected between 2000h-0800h in phase 1 of the study. ]
  
• Urinary cortisol and catecholamines on 12-hour urine collection. [ Time Frame: Urine sample will be collected between 2000h-0800h on Day 1 and Day 2 of the ambulatory phase (phase 2) of the study. ]
  
• Area under the curve for overnight plasma cortisol, growth hormone, glucagon, adrenaline and noradrenaline (based on hourly blood sample collection). [ Time Frame: Blood sample will be collected every hour beween 2000h-0800h in phase 1 of the study. ]
  
• Plasma metanephrines (based on blood sample collection) [ Time Frame: At 2000 P.M on Day 1 and 0800 A.M on Day 2 of phase 1 of the study. ]
  
• Plasma Cortisol, growth hormone, glucagon, adrenaline , noradrenaline and metanephrines based on blood sample collection. [ Time Frame: At 0800 A.M on Day 1 and 0800 A.M on Day 5 of phase 2. ]
  
• Urinary cortisol and catecholamines on 12-hour urine collection. [ Time Frame: Urine sample will be collected between 0800h and 2000h on Day 2 of phase 1 of the study. ]
  
• Urinary cortisol and catecholamines on 12-hour urine collection. [ Time Frame: Urine sample will be collected during between 0800h and 2000h of Day 1 and Day 2 of the ambulatory phase (phase 2) of the study. ]
  
• Sleep quality includes: total sleep time, sleep onset latency, sleep-efficiency, and wakefulness after sleep onset (WASO), total and average activity counts based on Actigraph data. [ Time Frame: Actigraph data will be recorded constantly during Phase 1 of the study, an expected average of 24 hours. ]
  
• Sleep quality includes: total sleep time, sleep onset latency, sleep-efficiency, and wakefulness after sleep onset (WASO), total and average activity counts based on Actigraph data and the Pittsburgh Sleep Quality Index scores. [ Time Frame: Actigraph data will be recorded constantly during the ambulatory phase (phase 2) of the study, an expected average of 5 days. Pittsburg Sleep quality Index tool will be done on day 1 and day 5 of phase 2. ]
  
• Parameters of Inflammation and Oxidative Stress include: Cell Adhesion Molecules, Myeloperoxidase, Oxidised LDL, hs-CRP (based on blood sample collection) and Urinary isoprostanes. [ Time Frame: At 2000 P.M on Day 1 and 0800 A.M on Day 2 of phase 1 of the study. ]
  
• Parameters of Inflammation and Oxidative Stress include: Cell Adhesion Molecules, Myeloperoxidase, Oxidised LDL, hs-CRP (C reactive Protein) based on blood sample collection, and Urinary isoprostanes. [ Time Frame: At 0800 A.M on Day 1 and Day 5 of phase 2. ]
  
• Diabetes Treatment Satisfaction Questionnaire and Semi-Structured Interviews (Questionnaires will generate total scores for treatment satisfaction, fear of hypoglycaemia, diabetes-related distress and hypoglycemia impaired awareness). [ Time Frame: On Day 5 of Phase 2 of the study. ]
  
• Cognitive Assessment: CogState assessment battery outcome measures will be generated. Each battery test point will record participant response times and accuracy rates for all tasks performed. [ Time Frame: Twice daily (AM-test and PM-test sessions) on Day 1, Day 2, Day 3, Day 4, and Day 5 of phase 2 of the study. ]
  

At present, decisions regarding insulin dosing are made by the patient with intermittent support from their medical team. Even with glucose sensor augmented insulin pump therapy (SAPT), representing the most advanced technology currently available, there are emotional and intellectual demands placed upon the patient with the most well-educated, intelligent and diligent patients often unable to perfectly match insulin delivery with their varying requirements. SAPT does improve glycaemia in comparison with insulin pump therapy alone though a significant proportion of patients will still not meet target HbA1c (<7.0%). A Closed Loop (CL) system whereby a computerised algorithm reviews continuous glucose information to determine a T1D patient's insulin requirements and controls insulin delivery will potentially have a major impact upon acute and chronic complications of diabetes as well as upon their quality of life. Overnight glycaemic control, without the added challenge of meals, physical activity and stress, is a realistic initial application of CL in clinical practice.

This study aims to evaluate insulin pump therapy with an overnight CL system in comparison with current best available technology represented by SAPT in Type 1 Diabetes (T1D) patients, in both hospital and then at home. Outcomes of interest will include metabolic control and performance of the Medtronic CL overnight system compared with SAPT (OL), in both the Clinical Trials Centre (CTC) and in the home setting; the relationship between night-time and day-time metabolic control with CL and OL and nocturnal clinical, hormonal and inflammatory factors that may influence subsequent daytime metabolic control; anti-insulin antibody titres and dissociation constants (Rd) upon CL algorithm performance; sleep quality, cognition, satisfaction with treatment and psychological parameters.

A two phase randomised crossover study design is to be employed with the first phase conducted for a single night in the clinical trials centre and the second phase over 5 days in an ambulatory setting.