The effect of Hybrid Closed Loop insulin delivery on glucose control in patients with type 1 diabetes aged 12 - 25 years.

MiniMed (Trademark) 670G Insulin Pump Hybrid Closed Loop System. This system consists on an insulin pump (Medtronic 670G), a continuous glucose monitoring system (3rd generation Enlite sensor), and an algorithm within the insulin pump that calculates background (basal) insulin delivery according to changes in the sensor glucose value. The insulin pump and continuous glucose monitor communicate wirelessly. .The pump is small enough to fit in the palm of a hand, and is usually carried clipped to a belt. The pump is water resistant and is built to last 4 years. The hybrid closed-loop control algorithm is inbuilt into the insulin pump hardware. The glucose sensor is the size of a 20 cent coin and clips on to the subcutaneously inserted glucose sensor. The sensor has an "inserter" and participants will be trained to insert the sensors themselves by a diabetes educator. The insulin pump and glucose sensor transmitter communicate wirelessly, with a range of approximately 6 meters. Participants who are randomised to the hybrid closed loop system will be trained by a diabetes nurse educator. During the run-in phase all participants will receive education sessions on continuous glucose monitoring, and for those randomised to the hybrid closed loop system will have additional training. The following is an outline of the visit history during the run-in phase which also describes the duration and frequency of sessions, and also the post randomisation training required for those participants who go on to the intervention. Visit 1: Screening and Consent (4 hours) 1. Confirm participant is able to take part in the study. 2. sign a consent form. 3. Collect baseline data including height, weight and current diabetes treatment. 4. Ask the participant to complete some questionnaires about diabetes. 5. Collect a blood sample Visit 2: Run in and Education Planning (2 – 8 hrs) This visit is to plan individual education programs to review carbohydrate counting and teach those that don’t know how to do this. 1. Participants currently on pump therapy will see a dietician (1-2 hrs) to review carbohydrate counting and a diabetes educator to assess pump download capability and review settings 2. Participants on injections will have between 1 – 3 sessions with a dietician to teach carb counting if required (which may be extended over 3 weeks if required). Participants on injections will get an individually programmed Aviva Expert glucometer to help with carbohydrate counting. Participants will not be able to continue with the rest of the study until this is learned. Visit 3: Sensor Insertion and Training (4 hours) All participants will be asked to come in the Research clinic to be fitted with a blinded sensor 1. We will teach the participant how to insert a sensor and give you a Contour Next glucometer (to use in addition to your usual glucometer) to record BGLs at least 4 times a day 2. We will also give a logbook and ask participants to record signs and treatment of a hypo, time off work/school and insulin dosing (MDI patients) Visits 4 and 5: Sensor Download (30 mins each) These visits will occur at 7 and 14 days after visit 3 to: 1. Download the sensor and glucometer data 2. Change the sensor and transmitter 3. Check that the log book is up to date Visit 4 and 5 may be able to happen at the participant location. Visit 6: Sensor Download and Randomization (4 hours) At this visit we will: 1. Check that sensor data is complete (if not participant will be offered a further 2 weeks of CGM collection to stay in the study) 2. Collect diabetes clinical data as in Visit 1 3. Collect logbook data 4. Participants will then be randomized to either stay on usual treatment (Control Group), or to the hybrid closed loop system (Intervention Group). Visit 7: Entry into Study Arm (1 hour) The schedule for this visit will depend on randomization and baseline therapy: (i) Control Group 1. Both injections and pump participants will be issued with a new logbook (ii) Intervention Group 1. Injections to HCL: Participant to come in for the following visits to teach how to operate the pump, insert sensors and use the hybrid closed loop function (HCL): Visit 7A: (4 hours) Initial Minimed 670G insulin pump training with a diabetes educator Visit 7B: Return to the clinic within 3 days to observe insulin line change if required. We will contact participant by phone/email as often as required to see how they are managing and ask them to upload your pump every week Visit 7C: (2 hours) 2 weeks after starting on the pump we will ask the participant to come in to the research clinic for sensor training. This will include inserting and changing the sensor and setting alarms. We will provide the participant with a sensor user guide and enough sensors for the duration of the study Visit 7D: (1-2 hours) This session will occur a minimum of 3 days after sensor training and will focus on learning how to initiate and operate the hybrid closed loop function. There will also be the opportunity to practice sensor change. When starting closed loop we will ask the participant to avoid excessive exercise for 48 hours. We will issue a new logbook to include documenting problems with the pump and sensors. We will continue to contact the participant by phone/email each week (or more often if required) over the next 4 weeks and ask the participant to upload the pump weekly Pump to HCL: We will ask the participant to come in to the clinic for the following visits to teach them how to operate the pump, insert sensors and use the closed loop function: Visit 7A: (1 – 4 hours) This session is to provide sensor and Minimed 670G pump training. This will include linking the sensor to the pump. We will provide them with a sensor user guide and enough sensors for the duration of the study Visit 7B: (1 – 2 hours) Following 3 – 7 days of using the sensor collection we will ask the participant to return to the clinic to change the sensor and show them how to start closed loop. This visit will be the same as Visit 7D (see above) Visit 8 (1 - 2 hours) face to face review (all participants), 4 weeks post randomisation Visits 9,10: (30 mins each). At week 11 and 12 post randomisation to collect blinded CGM Visit 11 (approx 4 hours). Mid point of study 13 weeks post randomisation. Repeat collection of auxological data, clinic data, and psychology questionnaires Visit 12,13, 14 (30 mins each), a week apart starting from week 23 post randomisation. To collected final blinded CGM. Visit 15 (4 hours), final study visit to complete biomarkers, clinical, auxological and psychology measures. The overall intervention period is 7 months (one month run in, and 6 months post randomisation). Adherence will be monitored by a data monitoring service at the NHMRC clinical trials centre. This will be done by examining the hybrid closed loop system pump download data - which includes and adherence report. All data is intention to treat analysis, so participants will be under no pressure to continue the intervention if they wish to withdraw