Closed-loop Control of Glucose Levels (Artificial Pancreas) During Exercise in Adults With Type 1 Diabetes

Institut de Recherches Cliniques de Montreal

Status and phase: Completed; Phase 2

Conditions: Type 1 Diabetes

Treatments: Other: 60-minute exercise; Other: 40-minute interval exercise

Study type: Interventional

Funder types: Other

Identifiers

NCT01930110

CLASS-06

Details and patient eligibility

About

Closed-loop strategy 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. A dual-hormone closed-loop system would regulate glucose levels through the infusion of two hormones: insulin and glucagon.

The objective is to compare the efficacy of single-hormone closed-loop strategy and dual-hormone closed-loop strategy at regulating glucose levels during continuous exercise and interval exercise.

The investigator hypothesized that dual-hormone closed-loop strategy is superior to single-hormone closed-loop strategy in regulating glucose levels during exercise periods.

Full description

Closed-loop strategy 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. A dual-hormone closed-loop system would regulate glucose levels through the infusion of two hormones: insulin and glucagon.

We aim to conduct a randomized two-way cross-over trial comparing single-hormone closed-loop strategy and dual-hormone closed-loop strategy to compare the two interventions during exercise periods in adults with type 1 diabetes. A moderate intensity exercise will be performed for 60 minutes at 60% of the maximum oxygen consumption (VO2max). A high intensity exercise will be 40 minutes of interval training. The interval training will be preceded by a 10 minutes warm-up and followed by a 10 minutes cool down.

Enrollment: 15 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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.
• Ongoing 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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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15 participants in 2 patient groups

Single-hormone closed-loop system

Active Comparator group

Description:

In single-hormone closed-loop system, variable subcutaneous insulin infusion rate will be used to regulate glucose levels

Treatment:

Other: 60-minute exercise

Other: 40-minute interval exercise

Dual-hormone closed-loop system

Active Comparator group

Description:

In dual-hormone closed-loop system, variable subcutaneous insulin and glucagon infusion rates will be used to regulate glucose levels

Treatment:

Other: 60-minute exercise

Other: 40-minute interval exercise