Proof of Concept - Identification of Patient-specific Parameters for Bolus Calculators for Type 1 Diabetes
Condition: Type1 Diabetes Mellitus
MeSH terms: Diabetes Mellitus, Type 1
Study type: Interventional

Summary: 
      The adoption of bolus calculators has been limited by the slow speed of the current trial and
      error approach. The goal of this project is to automate the determination of patient specific
      insulin pump parameters based on current automatic electronic logbooks of glucose
      measurements, carbohydrate intake, and insulin usage, by means of a mathematical model. More
      specifically, the investigators are interested in computing the carbohydrate to insulin ratio
      (CIR) and insulin sensitivity factor (ISF), which are the main parameters of bolus
      calculators.

      The present study is a proof-of-concept, open label, single arm clinical trial to validate
      the new method and refine both the mathematical model and the numerical techniques in
      well-regulated and disciplined type 1 diabetic subject.

      The study is a "trial" of the selected underlying mathematical model and the associated
      algorithms to simulate the glucose values of a patient with uncertain meal-data.
    

Detailed description: 
      After signing informed consent and checking eligibility criteria participants will receive
      uniform education related to self-monitoring of blood glucose and continuous glucose
      monitoring (CGM) using the CGM sensor as well as on the bolus calculator (BC). The study will
      take three weeks (or three sensors) per patient.

      Patients should live a close to normal life and should participate in their normal daily
      activities. During the study, patients must consequently keep using the BC of their insulin
      pump, record in the insulin pump when they eat extra food outside their regular meals and
      when they inject extra insulin without the use of their insulin pump. Faulty 'meal markers'
      have to be noted in a booklet and patients will also have to take pictures of their plate for
      each meal or record their meals in detail in a booklet. Patients should also consequently
      shut off insulin delivery when they disconnect their insulin pump and write it down in a
      booklet. The patients will be asked to wear an activity tracker (i.e. Fitbit), this data will
      help in the refinement of the model and will be used for research later in the same project.

      During the study, patients must skip a total of three meals: breakfast, lunch and dinner (not
      on the same day, but within the three weeks). This gives the investigators a period of
      measurements in which they know that there are no significant amounts of unpredictable
      carbohydrates in the blood. Patients can give correction insulin or take extra fast
      carbohydrates to correct the glycaemia when needed and record this in the insulin pump or in
      a booklet. The fast rescue carbohydrates should be in the form of Dextro energy tablets
      (provided by the study team).

      After the three weeks, patients will come back to the hospital where the study team will
      download data from the insulin pump, CGM sensor, and activity tracker. The booklet and
      photographs of the meals will be handed over to the study team. This is the end of the study
      for the patient. The collected patient data will further be used to assess the model fit of
      the chosen mathematical model as in, i.e. the investigators evaluate how well the model is
      able to reproduce the collected data.
    

Intervention name(s): Gathering data
Intervention type(s): Other
Intervention description(s): Gathering data about sleep, heart rate, carbohydrate intake, insulin pump, continuous glucose sensor, meals.
Intervention model: Single Group Assignment
Intervention model description: proof-of-concept, open label, single arm
Masking: None (Open Label)
Primary purpose: Other
Keywords: type 1 diabetes; insulin pump; bolus calculator; continuous glucose monitoring; carbohydrate to insulin ratio; insulin sensitivity factor