A Single-blind, Randomized, Cross-over Study to Assess the Efficacy of Single-hormone Closed-loop Strategy at Preventing Hypoglycemia During Unannounced and Announced Exercise in Adults With Type 1 Diabetes
Overview
- Phase
- Phase 2
- Intervention
- 60-minute exercise
- Conditions
- Type 1 Diabetes
- Sponsor
- Institut de Recherches Cliniques de Montreal
- Enrollment
- 37
- Locations
- 1
- Primary Endpoint
- Percentage of time of plasma glucose levels spent below 3.9 mmol/L
- Status
- Completed
- Last Updated
- 7 years ago
Overview
Brief Summary
Regular physical activity is associated with many health benefits for individuals with type 1 diabetes including improved cardiovascular fitness and vascular health, decreased insulin requirements, improved body composition and quality of life. However, exercise-induced hypoglycemia is very frequent and thus is the main limiting factor for physical activity practice in this population.
The artificial pancreas 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 artificial pancreas has the potential to reduce the risk of exercise-induced hypoglycemia but the importance of announcing exercise to the artificial pancreas is yet to be explored.
The objective of this study is to investigate 1) if announcing postprandial exercise to the artificial pancreas is beneficial in reducing the risk of hypoglycemia and 2) if an insulin bolus reduction is necessary when announcing the exercise to the artificial pancreas.
Investigators
Rémi Rabasa-Lhoret
Professor of Medicine
Institut de Recherches Cliniques de Montreal
Eligibility Criteria
Inclusion Criteria
- •Males and females ≥ 18 years of old.
- •Clinical diagnosis of type 1 diabetes for at least one year.
- •The subject will have been on insulin pump therapy for at least 3 months.
- •Last (less than 3 months) HbA1c ≤ 12%.
Exclusion Criteria
- •Clinically significant microvascular complications: nephropathy (estimated glomerular filtration rate below 40 ml/min), neuropathy (especially diagnosed gastroparesis) or severe proliferative retinopathy as judged by the investigator.
- •Recent (\< 3 months) acute macrovascular event e.g. acute coronary syndrome or cardiac surgery.
- •Use of medication with an effect on heart rate (e.g. beta-blockers).
- •Abnormal blood panel and/or anemia.
- •Ongoing or planned pregnancy.
- •Severe hypoglycemic episode within two weeks of screening.
- •Other serious medical illness likely to interfere with study participation or with the ability to complete the exercise periods by the judgment of the investigator (e.g. orthopedic limitation).
- •Failure to comply with team's recommendations (e.g. not willing to eat snack, not willing to change pump parameters, etc).
- •Problems with venous access.
Arms & Interventions
Unannounced exercise
The target blood glucose of the algorithm will be as usual. A pre-meal full insulin bolus will be given.
Intervention: 60-minute exercise
Unannounced exercise
The target blood glucose of the algorithm will be as usual. A pre-meal full insulin bolus will be given.
Intervention: Insulin pump
Unannounced exercise
The target blood glucose of the algorithm will be as usual. A pre-meal full insulin bolus will be given.
Intervention: Dexcom G4 Platinum glucose sensor
Unannounced exercise
The target blood glucose of the algorithm will be as usual. A pre-meal full insulin bolus will be given.
Intervention: Insulin
Unannounced exercise
The target blood glucose of the algorithm will be as usual. A pre-meal full insulin bolus will be given.
Intervention: Single-hormone closed-loop strategy
Announced exercise with pre-meal full bolus
The target blood glucose of the algorithm will be increased and a pre-meal full bolus will be given
Intervention: 60-minute exercise
Announced exercise with pre-meal full bolus
The target blood glucose of the algorithm will be increased and a pre-meal full bolus will be given
Intervention: Insulin pump
Announced exercise with pre-meal full bolus
The target blood glucose of the algorithm will be increased and a pre-meal full bolus will be given
Intervention: Dexcom G4 Platinum glucose sensor
Announced exercise with pre-meal full bolus
The target blood glucose of the algorithm will be increased and a pre-meal full bolus will be given
Intervention: Insulin
Announced exercise with pre-meal full bolus
The target blood glucose of the algorithm will be increased and a pre-meal full bolus will be given
Intervention: Single-hormone closed-loop strategy
Announced exercise with reduced insulin bolus
The target blood glucose of the algorithm will be increased and the pre-meal insulin bolus will be reduced by 33%.
Intervention: 60-minute exercise
Announced exercise with reduced insulin bolus
The target blood glucose of the algorithm will be increased and the pre-meal insulin bolus will be reduced by 33%.
Intervention: Insulin pump
Announced exercise with reduced insulin bolus
The target blood glucose of the algorithm will be increased and the pre-meal insulin bolus will be reduced by 33%.
Intervention: Dexcom G4 Platinum glucose sensor
Announced exercise with reduced insulin bolus
The target blood glucose of the algorithm will be increased and the pre-meal insulin bolus will be reduced by 33%.
Intervention: Insulin
Announced exercise with reduced insulin bolus
The target blood glucose of the algorithm will be increased and the pre-meal insulin bolus will be reduced by 33%.
Intervention: Single-hormone closed-loop strategy
Outcomes
Primary Outcomes
Percentage of time of plasma glucose levels spent below 3.9 mmol/L
Time Frame: From 9:30 to 11:30 (120 minutes)
Secondary Outcomes
- Relative decrease in glucose levels during exercise compared to pre-breakfast levels(From 8:00 to 10:50 (170 minutes))
- Percentage of time of plasma glucose levels spent above 10 mmol/L(From 9:30 to 10:30 (60 minutes))
- Mean time (minutes) to the first hypoglycemic event(From 9:30 to 10:30 (60 minutes))
- Decremental area under the curve from the start of the exercise(From 9:30 to 11:00 (90 minutes))
- Number of patients experiencing exercise-induced hypoglycemia requiring treatment(From 9:30 to 10:30 (60 minutes))
- Percentage of time of plasma glucose levels spent above 13.9 mmol/L(From 9:30 to 10:30 (60 minutes))
- Percentage of time of plasma glucose levels spent above 16.7 mmol/L(From 9:30 to 10:30 (60 minutes))
- Mean plasma glucose levels(From 8:00 to 11:30 (210 minutes))
- Percentage of time of plasma glucose levels spent below 3.9 mmol/L(From 9:30 to 10:30 (60 minutes))
- Percentage of time of plasma glucose levels spent below 3.3 mmol/L(From 9:30 to 10:30 (60 minutes))
- Percentage of time of plasma glucose levels spent below 2.8 mmol/L(From 9:30 to 10:30 (60 minutes))
- Percentage of time of plasma glucose levels spent between 3.9 and 7.8 mmol/L(From 9:30 to 10:30 (60 minutes))
- Standard deviation of glucose levels(From 8:00 to 11:30 (210 minutes))
- Coefficient of variation of glucose levels(From 8:00 to 11:30 (210 minutes))