Timing of Pre-meal Insulin Versus Accurate Carbohydrate Counting in Youth With Type 1 Diabetes

University of Colorado Denver (CU Denver)

Status: Completed

Conditions: Type 1 Diabetes

Treatments: Other: Bolus timing and dosing

Study type: Interventional

Funder types: Other

Identifiers

NCT01209312

09-0931

Details and patient eligibility

About

The investigators are hoping to figure out how youth with type 1 diabetes can best control their blood glucose levels after meals, by determining whether accurate carbohydrate dosing or the timing of the bolus is more important. There is evidence to suggest that each strategy is important for blood glucose control. Unfortunately, for some people, prebolusing is difficult, because they may not know how much they are going to eat. To give an exact dose of insulin 20 minutes before a meal can be difficult. In this study, the investigators would like to show that taking even just part of the insulin bolus 20 minutes before the meal is preferable to waiting until mealtime and taking the entire bolus. To do this, the investigators will have 24 patients in the study, who will each spend 4 mornings at The investigators clinic. The order of the visits will be selected randomly. The visits will include: taking full bolus at mealtime, taking full bolus 20 minute before mealtime, taking ½ bolus at mealtime, and taking ½ bolus 20 minutes before mealtime. At each visit, the person will eat the same meal, but the timing and amount of the bolus will be different. The investigators will measure the blood glucose levels with a blood glucose meter, and also with a laboratory test called YSI. The investigators will also be measuring the glucose levels under the person's skin with a continuous glucose monitor. The investigators will compare the area under the curve for the different visits, as well as the glucose levels at different points after the meal.

Enrollment: 21 patients

Sex: All

Ages: 7 to 21 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Ages 7-21, inclusive
• Diagnosis of type 1 diabetes for >1 year
• Using carbohydrate counting to dose mealtime insulin
• Using an insulin pump and continuous glucose monitor to control diabetes
• HbA1c <10%

Exclusion criteria

• Celiac disease or other GI abnormality
• Severe hypoglycemia in the past 6 months
• Pregnancy
• Documented hypoglycemia unawareness

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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21 participants in 4 patient groups

full bolus -20

Experimental group

Description:

Will administer full insulin bolus 20 minutes prior to meal

Treatment:

Other: Bolus timing and dosing

Full bolus, T0

Experimental group

Description:

Will administer full meal bolus at the start of the meal

Treatment:

Other: Bolus timing and dosing

1/2 bolus, T-20

Experimental group

Description:

Will only give half the insulin dose 20 minutes before meal

Treatment:

Other: Bolus timing and dosing

1/2 bolus T0

Experimental group

Description:

Will give half the amount of insulin at the time of the meal

Treatment:

Other: Bolus timing and dosing