Does real-time patient analysis of continuous glucose monitor data improve glycaemic control in patients with Type 1 diabetes on insulin pump therapy?

In recent years, continuous glucose monitoring systems have been developed. Most currently available continuous glucose monitors measure glucose with minimal invasiveness through continuous measurement of interstitial fluid. Results from earlier models/ systems are only available retrospectively (eg with MiniMed CGMS or CGMS Gold devices information is downloaded after a 72 hour monitoring period), however newer models (eg MiniMed Guardian RT; RT= real time) incorporate technology for real-time display of glucose readings directly to the patient. In addition, real-time CGMs include an arrow on the display panel that indicates an upward or downward trend in glucose levels, allowing patients to predict the likelihood of needing to make appropriate adjustments to their immediate management to avoid hypo- or hyperglycaemia. The recent escalation in the use of insulin pump therapy worldwide has been accompanied by significant advances in device technology. The MMT 722 device is the first integrated insulin pump system with inbuilt real-time continuous glucose readings available worldwide. To date this device has received CE Mark approval for use in Europe (CE Marking 0459/0976) and Health Canada regulatory approval in Canada. An application for TGA approval for use in Australia has been submitted. The MMT 722 provides two independent functions– the delivery of insulin using standard basal/bolus insulin pump protocols and display of real time glucose values, trends and graphs from a subcutaneous continuous glucose sensor. Sensor readings are transmitted by radiofrequency signal every 5 minutes and shown on the display panel of the pager-sized pump device. In addition, alarms can be set to alert the patient of impending excursion to the hypo- or hyperglycaemic ranges. It is anticipated that the availability of this new combined insulin pump and continuous real-time glucose monitor will enable patients to make informed therapeutic decisions which would ultimately translate into improved patient-driven glucose control by increasing the time spent in the normoglycaemic range. Hypothesis: That the integration of real-time continuous glucose monitor data with an insulin pump device helps individuals with Type 1 diabetes to achieve improved glycaemic control and quality of life. Aim: To assess the impact of the use of The MiniMed Paradigm Real-time Insulin Pump and Continuous Monitoring System (MMT 722) on glycaemic control and quality of life in adolescents and young people with Type 1 diabetes. Methodology: Randomised Control Trial conducted at five sites in Australia. Sites involved in the project are: 1. Royal Children’s Hospital, Victoria 2. Royal Melbourne Hospital, Victoria 3. St Vincent’s Hospital, Victoria 4. The Children’s Hospital at Westmead, New South Wales 5. Princess Margaret Hospital for Children, Western Australia The total study duration will be 6 months, during which the actual device trial intervention period will last for three months. Each site will recruit patients who will subsequently be randomised into two groups (1:1): an intervention group and a control group. The ‘intervention’ group will wear and use the MMT 722 device for the duration of the trial intervention period (3 months), while the ‘control’ group will continue to use their own pre-trial insulin pump device (no new intervention). While patients in the ‘intervention’ group will have access to continuous glucose readings on the display monitor of their pump, they will be instructed to continue SMBG in their usual manner (ie at least 4 times / day; usually fasting / pre-meals). All real time glucose readings that may provoke potential treatment decisions should be confirmed by a concomitant SMBG reading. Patients in the control group will continue to perform regular (4/day, as above) SMBG levels / day and treatment decisions will be based on these readings in the usual manner. The two main physical components of the MMT 722 device are the continuous glucose sensor and the insulin pump device. The insulin pump device will be worn continuously throughout the trial period by participants in the intervention group (in place of their usual insulin pump device). The sensor component is designed to be used on either a continuous or intermittent basis. As the purpose of this trial is to determine the impact of continuous real time glucose readings on patient-initiated therapeutic interventions, the intervention group will be required to wear the sensor for >70% of the 3 month intervention period. This project is a pilot study of a new therapeutic device to assess its acceptability to patients and its potential impact on glycaemic control. To date therefore, no baseline data to derive power calculations are currently available. Our sample size of 40-50 patients in total has been empirically chosen and is subject to constraint by the limited availability of the MMT 722 devices in Australia. In total there will be between 20 and 25 patients in the intervention group (either four or five patients at each site) and an equal number in the control group at each site. Measurement tools: 1) Glycaemic status pre- trial intervention period: One week of Medtronic Minimed continuous glucose monitoring system (CGMS Gold) device data will be recorded on all subjects. This CGMS Gold device does not give real-time glucose readings but stores data for retrospective analysis. Results will only be available once the stored data is downloaded at the end of the study period. 2)Glycaemic status post- trial intervention period: In the Intervention group, MMT 722 CGMS data from the final week of the 3 month period will be analysed (participants will be required to wear the sensor 100% of time during this week) The Control group will have repeat Medtronic CGMS Gold recording over the final week of the 3 month period. 3)Quality of Life measures used will be validated tools for use in diabetes. (DQOL for adult participants; DQoLY for adolescents up to age 18). 4)HbA1C will be measured centrally at DCCT accredited lab (Austin Health, Victoria).