The Steno Opti-Bolus-Timing Studies

Not Applicable

Not yet recruiting

• Conditions: Type 1 Diabetes (T1D)

• Registration Number: NCT07021690
• Lead Sponsor: Steno Diabetes Center Copenhagen

Brief Summary

The project investigates the significance of the timing of insulin dosing for breakfast and lunch with an automated insulin pump and whether it matters if the meal primarily contains high or low glycemic index carbohydrates.

We hypothesise that a bolus given 15 minutes before the meal will result in the best blood glucose levels after the meal, regardless of the type of carbohydrates.

Participants will attend 6 experimental days over a maximum of 3 months, where they will be served either breakfast or lunch at the research site, depending on sub-study (breakfast or Lunch sub-study). Three different bolus timings will be tested, with either rapidly absorbed carbohydrates or slowly absorbed carbohydrates, in a randomized order for each participant. Participants will take insulin for the meal using the bolus calculator in the pump, either 15 minutes before, at the start of the meal, or 30 minutes after the meal. The development in sensor glucose will then be monitored for up to 4 hours after the meal.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2025-05-23
• Status Verified: 2025-06
• Study First Submitted QC: 2025-06-13
• Last Update Submitted: 2025-06-13
• Study First Posted: 2025-06-15
• Last Update Posted: 2025-06-15
• Study Start: 2025-06-30
• Primary Completion: 2026-05
• Study Completion: 2027-06

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Change in SG between three meal bolus delivery times for meals with two levels of glycemic index	From -15 min before the meal to 270 min after meal intake	The primary objective is to compare the change in SG (from -15 min before the meal to the highest SG level measured during 0-270 min after start of meal intake) between three meal bolus delivery times for meals with two levels of glycemic index (GI) (high-GI and low-GI meals, respectively).

Secondary Outcome Measures

Name	Time	Method
Difference in amount of insulin given for autocorrections during the post-meal period between the three bolus methods for each type of meal.	From -15 min before the meal to 270 min after meal intake
Area under the post-meal CGM-curve	From -15 min before the meal to 270 min after meal intake
Distribution of Time Below Range (TBR)	From -15 min before the meal to 270 min after meal intake	Distribution of TBR in the observation period of 4 hours and 45 minutes around the meal between the three bolus methods for each GI meal.
Difference in the number of Time Below Range events (with SG< 3.9 mmol/l)	From -15 min before the meal to 270 min after meal intake	Difference in the number of Time Below Range (TBR) events (with SG\< 3.9 mmol/l) in the observation period of 4 hours and 45 minutes around the meal between the three bolus methods for each GI meal.
Distribution of Time In target Range (TIR)	From -15 min before the meal to 270 min after meal intake	Distribution of Time In target Range (TIR) in the 4 hours and 45 minutes observation period around the meal between the three bolus methods for each GI meal.
Distribution of Time In Tight target Range (TITR)	From -15 min before the meal to 270 min after meal intake	Distribution of Time In Tight target Range (TITR), in the 4 hours and 45 minutes observation period around the meal between the three bolus methods for each GI meal.
Distribution of Time Above Range (TAR)	From -15 min before the meal to 270 min after meal intake	Distribution of Time Above Range (TAR), in the 4 hours and 45 minutes observation period around the meal between the three bolus methods for each GI meal.
Number of hypoglycemia events (PG< 3.9 mmol/L )	From -15 min before the meal to 270 min after meal intake

Trial Locations

Locations (1)

Steno Diabetes Center Copenhagen Clinical Translational Research, Diabetes Technology; 🇩🇰 Herlev, Denmark