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

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.

Study Overview

• Status: Completed
• Conditions: Type 1 Diabetes
• Intervention / Treatment: Other: Bolus timing and dosing

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Colorado
    • Aurora, Colorado, United States, 80045
      • Barbara Davis Center for Childhood Diabetes

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 7 years to 21 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: full bolus -20; Will administer full insulin bolus 20 minutes prior to meal	Other: Bolus timing and dosing; We will be altering the timing and dosages of the prescribed meal bolus.
Experimental: Full bolus, T0; Will administer full meal bolus at the start of the meal	Other: Bolus timing and dosing; We will be altering the timing and dosages of the prescribed meal bolus.
Experimental: 1/2 bolus, T-20; Will only give half the insulin dose 20 minutes before meal	Other: Bolus timing and dosing; We will be altering the timing and dosages of the prescribed meal bolus.
Experimental: 1/2 bolus T0; Will give half the amount of insulin at the time of the meal	Other: Bolus timing and dosing; We will be altering the timing and dosages of the prescribed meal bolus.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Blood glucose area under the curve	4 hours post-meal

Collaborators and Investigators

• Sponsor: University of Colorado, Denver
• Investigators: Principal Investigator: H Peter Chase, MD, University of Colorado, Denver

Study record dates

Study Major Dates

• Study Start: December 1, 2009
• Primary Completion (Actual): December 1, 2010
• Study Completion (Actual): December 1, 2010

Study Registration Dates

• First Submitted: September 23, 2010
• First Submitted That Met QC Criteria: September 24, 2010
• First Posted (Estimate): September 27, 2010

Study Record Updates

• Last Update Posted (Estimate): November 22, 2012
• Last Update Submitted That Met QC Criteria: November 20, 2012
• Last Verified: November 1, 2012

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Immune System Diseases; Autoimmune Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1
• Other Study ID Numbers: 09-0931