Assessment of the Efficacy of the Artificial Pancreas Combined With a Qualitative Meal Size Estimation to Control Postprandial Glucose Levels

Not Applicable

Completed

• Conditions: Type 1 Diabetes
• Interventions: Device: Single-hormone closed-loop system; Device: Insulin pump; Device: Continuous glucose monitoring system; Drug: Aspart or Lispro; Other: Carbohydrate counting; Other: Simplified qualitative meal-size estimation strategy; Other: 3-week intervention; Other: 1-hour postprandial exercise (sub-study); Other: 2-hour postprandial exercise (sub-study); Other: Exercise announcement and meal bolus reduction (sub-study)

• Registration Number: NCT04031599
• Lead Sponsor: Institut de Recherches Cliniques de Montreal

Brief Summary

Postprandial glycemic excursions are major determinants of overall glycemic control in type 1 diabetes. Carbohydrate content of ingested meals is the main determinant of post-meal glucose excursion. Accurate carbohydrate counting is a critical aspect of managing postprandial blood glucose levels. accurate carbohydrate counting is considered by patients as a significant burden and frustrating task.

The closed-loop system (CLS) is composed of three components: glucose sensor to read glucose levels, insulin pump to infuse insulin and a dosing mathematical algorithm to decide on the required insulin dosages based on the sensor's readings.

The objective of this study is to compare the efficacy of two strategies to regulate glucose levels in outpatient settings in adults with type 1 diabetes: 1) single-hormone CLS with rapid acting insulin analogue combined with carbohydrate counting; 2) single-hormone CLS with rapid acting insulin analogue combined with simplified qualitative meal-size estimation.

A sub-study will also be proposed to participants. Postprandial exercise combines two situations complicating CLS operation: a high plasma insulin due to insulin on-board related to meal boluses and rapid blood glucose changes (postprandial blood glucose excursion and then drop during exercise) making input from the glucose sensor less accurate. The objective of this sub-study will be to explore the safety and efficacy of the CLS using the combined strategy of pre-meal exercise announcement and meal bolus reduction of 33% when exercise is performed 1 hour compared to 2 hours post meal time.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2019-07-22
• Study First Submitted QC: 2019-07-22
• Study First Posted: 2019-07-24
• Study Start: 2020-07-10
• Primary Completion: 2021-11-27
• Study Completion: 2021-12-14
• Status Verified: 2022-01
• Last Update Submitted: 2022-01-13
• Last Update Posted: 2022-01-28

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Simplified qualitative meal size estimation	Aspart or Lispro	Rapid acting insulin analogue with simplified qualitative meal size estimation
Carbohydrate counting	Aspart or Lispro	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	3-week intervention	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	1-hour postprandial exercise (sub-study)	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	Continuous glucose monitoring system	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	Carbohydrate counting	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	Exercise announcement and meal bolus reduction (sub-study)	Rapid acting insulin analogue with carbohydrate counting
Simplified qualitative meal size estimation	Insulin pump	Rapid acting insulin analogue with simplified qualitative meal size estimation
Carbohydrate counting	Single-hormone closed-loop system	Rapid acting insulin analogue with carbohydrate counting
Carbohydrate counting	Insulin pump	Rapid acting insulin analogue with carbohydrate counting
Simplified qualitative meal size estimation	Single-hormone closed-loop system	Rapid acting insulin analogue with simplified qualitative meal size estimation
Simplified qualitative meal size estimation	3-week intervention	Rapid acting insulin analogue with simplified qualitative meal size estimation
Carbohydrate counting	2-hour postprandial exercise (sub-study)	Rapid acting insulin analogue with carbohydrate counting
Simplified qualitative meal size estimation	Continuous glucose monitoring system	Rapid acting insulin analogue with simplified qualitative meal size estimation
Simplified qualitative meal size estimation	Simplified qualitative meal-size estimation strategy	Rapid acting insulin analogue with simplified qualitative meal size estimation

Primary Outcome Measures

Name	Time	Method
Percentage of time of glucose levels spent between 3.9 and 10.0 mmol/L	504 hours
Relative decrease in glucose levels during exercise compared to pre-breakfast levels (sub-study)	3.5 or 4.5 hours	Difference between pre-breakfast levels and the lowest glucose level from the start of the exercise until the end of exercise

Secondary Outcome Measures

Name	Time	Method
Total number of hours of sensor availability	378 hours
Percentage of time of sensor availability	504 hours
2-hour postprandial glucose levels over the last 3 days of the intervention.	18 hours
Average number of phone calls per participant related to CLS technical issues	504 hours
Number of days with hypoglycemic events less than 3.1 mmol/L	252 hours
Average number of days per participant requiring study team support for at least one technical problem	21 days
Percentage of time of glucose levels spent below 2.8 mmol/L	504 hours
Percentage of time of plasma glucose levels spent below 3.3 mmol/L (sub-study)	1.5 hour	Post-exercise period
Percentage of time of glucose levels spent below 3.9 mmol/L	504 hours
Percentage of time of glucose levels spent above 10.0 mmol/L	504 hours
Mean glucose levels	504 hours
Fasting glucose levels	504 hours
Standard deviation of insulin delivery	504 hours
Coefficient of variance of insulin delivery	504 hours
Between-day variability in insulin delivery	504 hours
Number of nights with hypoglycemic events less than 3.1 mmol/L	126 hours
Percentage of time of glucose levels spent above 16.7 mmol/L	504 hours
Number of hours and percentage of time in open-loop and closed-loop modes	504 hours
Decrease in plasma glucose levels during exercise (sub-study)	1 hour	Difference between glucose levels at the beginning of the exercise and the lowest glucose levels from the start of the exercise until the end of exercise
Percentage of time of glucose levels spent below 3.3 mmol/L	504 hours
Percentage of time of glucose levels spent above 13.9 mmol/L	504 hours
Total insulin delivery	504 hours
Number of hypoglycemic events less than 3.1 mmol/L	504 hours
Percentage of time of glucose levels spent between 3.9 and 7.8 mmol/L	504 hours
Coefficient of variance of glucose levels	504 hours
Relative decrease in glucose levels during exercise compared to pre-breakfast levels (sub-study)	2 or 3 hours	Difference between pre-breakfast levels and the lowest glucose level from the start of the exercise until the end of exercise
Percentage of time of plasma glucose levels spent above 16.7 mmol/L (sub-study)	1.5 hour	Post-exercise period
Percentage of time of plasma glucose levels spent above 13.3 mmol/L (sub-study)	1.5 hour	Post-exercise period
Standard deviation of glucose levels	504 hours
Between-day variability in glucose levels	504 hours
Percentage of time of plasma glucose levels spent below 3.0 mmol/L (sub-study)	1.5 hour	Post-exercise period
Percentage of time of plasma glucose levels spent above 13.9 mmol/L (sub-study)	1 or 2 hours	Pre-exercise period (from mealtime to exercise onset)
Percentage of time of plasma glucose levels spent below 3.9 mmol/L (sub-study)	1.5 hour	Post-exercise period
Percentage of time of plasma glucose levels spent between 3.9 and 10.0 mmol/L (sub-study)	1.5 hour	Post-exercise period
Percentage of time of plasma glucose levels spent above 10.0 mmol/L (sub-study)	1.5 hour	Post-exercise period
Number of patients experiencing hypoglycemia requiring treatment (sub-study)	3.5 or 4.5 hours	Overall study period
Mean time (minutes) to the first hypoglycemic event (sub-study)	1 hour	Exercise period

Trial Locations

Locations (2)

Montreal Clinical Research Institute; 🇨🇦 Montreal, Quebec, Canada

McGill University Health Center; 🇨🇦 Montreal, Quebec, Canada