MedPath

Blood Glucose Target Before and During Exercise in Adults With Type 1 Diabetes Using an Artificial Pancreas

Not Applicable
Recruiting
Conditions
Type 1 Diabetes
Registration Number
NCT05821322
Lead Sponsor
Institut de Recherches Cliniques de Montreal
Brief Summary

Despite major technological advances in type 1 diabetes (artificial pancreas), the management of hypoglycemia remains a major challenge, especially during and after physical activity. The primary outcome is to determine the temporary blood glucose (BG) target to be set 60 minutes before aerobic exercise in people with type 1 diabetes (PWT1D) using do-it-yourself automated insulin delivery (DIY-AID) systems. Three glycemic thresholds to be applied 60 minutes before physical activity will be tested in 32 people on AID-DIY: 8.3 (current target for commercial AID systems), 8.8, and 9.3 mmol/L. Each participant will perform 3 sessions of moderate aerobic physical activity (ergocycle) at 60% of vo2peak with a different glycemic target each time (random order). Plasma glucose will be measured every 20 minutes before and during physical activity, and blood glucose measured by continuous glucose reading (DEXCOM) for 24 hours post-intervention. Once the best glycemic target is selected, participants could come to the research center for 1 or 2 more voluntary interventions to test the threshold during 1) fasting exercise and 2) late luteal phase of the menstrual cycle.

Detailed Description

This study follows a randomized, cross-over design and aims to test tree temporary BG targets (8.3, 8.8 and 9.3 mmol/L), resulting in 3 intervention visits per participants. A total of 32 participants will be recruited and randomized for this study.

Intervention visit:

* Participants will be admitted at the research center (IRCM; Montréal or Alberta) at 15:30.

* A venous catheter will be installed for plasma glucose and insulin measurements.

* At 16:00, the temporary BG target will be set in the DIY-AID system and blood sampling will begin.

* At 16:40, if glucose is \< 5.5 mmol/L, 16g carbohydrate (CHO; 4 Dex4®) will be provided.

* At 16:55, a smaller sample will be taken only to verify glucose level. If glucose is \< 5.5 mmol/L, 16g CHO (4 Dex4®) will be provided and exercise start will be postponed by at least 15 minutes or until glucose level is \> 5.5 mmol/L. If more than three CHO intake are needed, the test will be canceled and rescheduled.

* At 17:00, exercise will be started if glucose is \> 5.5 mmol/L. The exercise will consist of 60 minutes on the ergocycle at 60% of pre-determined VO2peak (moderate intensity).

* At 18:00, exercise and temporary BG target will be stopped. Blood sampling will continue for 1-hr during recovery.

* At 19:00, participant will be discharged. If glucose level is below 5.0 mmol/L, a snack of 16g CHO (4 Dex4®) will be offered. Participants will have the option to bring their dinner and eat it at the research facility before leaving if they prefer.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
32
Inclusion Criteria
  • Males and females aged between 18 and 65 years old.
  • Clinical diagnosis of type 1 diabetes for 1 year. (Note: The diagnosis of type 1 diabetes is based on the investigator's judgment; C peptide level and antibody determinations are not needed.)
  • Treatment using DIY-AID system for 3 months.
  • Own a smartphone or tablet to use the mobile application: Keenoa, Fitbit App
  • Using Dexcom G6 and willing to share CGM data with the research team.
  • Using rapid- (e.g., Aspart, Lispro or Glulisine) or ultra-rapid (e.g., FiAsp) acting insulin analogs.
  • HbA1c < 8.5%.
Exclusion Criteria
  • Major complication within the previous 3 months (e.g., severe hypoglycemia requiring assistance, diabetic ketoacidosis, or cardiovascular event).
  • Restriction in PA due to significant diabetes complications (e.g., severe peripheral neuropathy, active proliferative retinopathy, etc.) or other type of limitations (e.g., orthopedic, severe arthritis, etc.). Uncontrolled hypertension (e.g., blood pressure > 150 mmHg systolic or > 95 mmHg diastolic).
  • Ongoing pregnancy or breastfeeding.
  • Inability to give consent.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Primary Outcome Measures
NameTimeMethod
Change in plasma glucose during exercise60 minutes (during exercice)

To determine the temporary blood glucose (BG) target to be set 60 minutes before aerobic exercise in PWT1D using DIY-AID systems which will be associated with the smallest change in glucose during exercise by testing the targets of 8.3 (current target for commercial AID systems), 8.8, and 9.3 mmol/L.

Secondary Outcome Measures
NameTimeMethod
Time in range during exercice: menstrual cycle phases60 minutes (during exercice)

Volunteer participants will return in the luteal phase of the menstrual cycle to repeat the intervention at the glycemic threshold targeted during the primary outcome.

Number of participants who required oral treatment during exercise60 minutes (during exercice)

Number of participants who required oral treatment during exercise for: a) plasma glucose value \< 4.5 mmol/L and b) plasma glucose value \< 4.0 mmol/L.

Time in range (during fasting exercice)60 minutes (during exercice)

The intervention will be repeated at the glycemic threshold targeted during the primary outcome

Number of hypoglycemic episodes60 minutes (during exercice)

number of hypoglycemic episodes (plasma glucose \< 4.0 mmol/L) during exercise.

Insulin on board (units)60 minutes (during exercice)

Insulin on board or active insulin at exercise onset (Units will be collected on insulin pump) from start to finish

Mean CGM glucose24 hours post-exercice

post-exercice until 6 am

Plasma insulin60 minutes (during exercice)

plasma insulin changes from exercise start to finish (uU/mL)

Plasma glucose at 60 minutes60 minutes

plasma glucose level at the end of exercise

Carbohydrate consumption (g)60 minutes (during exercice)

amount of carbohydrate (CHO) needed to increase glucose value

Percent time in range, in hypoglycemia and in hyperglycemiamidnight to 6 am

Percentage of time \< 3.0 mmol/L, between 3.0-3.9 mmol/L, between 3.9-10.0 mmol/L, between 10.1-13.9 mmol/L, and \> 13.9 mmol/L post-exercice until 6 am

Coefficient of variation24 hours post-exercice

post-exercice until 6 am; assessed by the coefficient of variation

Hypoglycemia with treatmentmidnight to 6 am

Total number of hypoglycemia episodes requiring treatment

Glucose variability24 hours post-exercice

post-exercice until 6 am; assessed by the CGM standard deviation

Number of participants requiring an oral treatment for hypoglycemia24 hours post-exercice

Number of participants requiring an oral treatment for hypoglycemia (\< 3.9 mmol/L) until 6 am.

Carbohydrate needed (g)24 hours post-exercice

total amount of carbohydrate (CHO) needed to treat hypoglycemic events.

Lowest plasma glucose60 minutes (during exercice)

Lowest plasma glucose level during exercise

Trial Locations

Locations (1)

Institut de recherches cliniques de Montréal

🇨🇦

Montreal, Quebec, Canada

Institut de recherches cliniques de Montréal
🇨🇦Montreal, Quebec, Canada
Rémi Rabasa-Lhoret, MD, PhD
Contact
5149875666
remi.rabasa-lhoret@ircm.qc.ca

MedPath

Empowering clinical research with data-driven insights and AI-powered tools.

© 2025 MedPath, Inc. All rights reserved.