Impact of a Low-Carbohydrate Diet in Pediatric Type 1 Diabetes

Impact of a Low-Carbohydrate Diet on Glycemic Control and Lipids in Pediatric Type 1 Diabetes

Dietary carbohydrate consumption is a key factor influencing postprandial glycemia for patients with type 1 diabetes mellitus (T1DM). Because post-prandial glucose excursions profoundly influence hemoglobin A1c (HbA1c), therapeutic approaches to mitigate post-prandial hyperglycemia are of great importance. The quantity and source of carbohydrates affect post-prandial glycemia more than any other dietary factor. These findings serve as the physiologic basis for a growing interest in carbohydrate-restricted diets in the management of T1DM despite American Diabetes Association (ADA) guidelines that discourage restricting total carbohydrate intake to less than 130 grams per day. Although case series and prospective studies suggest low-carbohydrate diets (LCD) significantly improve HbA1c for adults with T1DM, data in the pediatric T1DM population is limited. The investigators will conduct a randomized prospective pilot study evaluating glycemic control, lipidemia, and quality of life (QOL) in pediatric T1DM patients on a LCD.

Study Overview

• Status: Completed
• Conditions: Type 1 Diabetes
• Intervention / Treatment: Other: Dietary Intervention

• Study Type: Interventional
• Enrollment (Actual): 39
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Nashville, Tennessee, United States, 37212
      • Vanderbilt University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 13 years to 21 years (Child, Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Diagnosed with T1DM for at least 12 months
• Age 13 to 21 years
• Total daily dose of insulin 0.5 to 1.25 units/kg/day
• Current use of an insulin pump and CGM
• HbA1c between 7% and 10%
• Tanner stage 3 to 5 on physical exam
• Participant or parent of participant use of smart phone
• Able to read and speak English

Exclusion Criteria:

• Any episode of diabetic ketoacidosis (DKA) in the last 12 months
• Any episode of severe hypoglycemia (defined as requiring assistance from another person, including coma, seizures, or episodes requiring glucagon, IV dextrose or oral carbohydrate administered by another person) in the last 12 months
• Any prior abnormal fasting lipid panel (LDL > 130)
• Additional dietary restrictions
• Following a weight-loss or otherwise restrictive diet
• Use of medication or supplements other than insulin to control blood glucose
• Use of medication or other supplements to lower lipids
• Pregnancy or breast feeding
• History of hemoglobinopathy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low Carbohydrate Diet; The investigators will prescribe isocaloric diets equaling the estimated energy requirements of the Institute of Medicine. Participants on the LCD intervention will consume 25-35% of total daily intake from carbohydrates, 45-65% from fat and 10-30% from protein.	Other: Dietary Intervention; The investigators will prescribe isocaloric diets equaling the estimated energy requirements of the Institute of Medicine with varying macronutrient content in each group.
Active Comparator: Standard Carbohydrate Diet; The investigators will prescribe isocaloric diets equaling the estimated energy requirements of the Institute of Medicine. Participants on the SCD intervention will consume 45-65% of total daily caloric intake from carbohydrates, 25-35% from fat and 10-30% from protein.	Other: Dietary Intervention; The investigators will prescribe isocaloric diets equaling the estimated energy requirements of the Institute of Medicine with varying macronutrient content in each group.
No Intervention: No Dietary Recommendations; This group will serve as a control that receives the same number of education sessions as LCD and SCD group to teach general diabetes management but without specific dietary recommendations.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HbA1c	HbA1c (%) change will be measured from baseline to 12 weeks	Baseline to week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent of Time Spent in the Glycemic Target of 70 - 140 mg/dL	Percent of time is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to Week 12
Percent of Time Spent Above the Glycemic Target of 140 mg/dL	Percent of time is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to Week 12
Percent of Time Spent Below the Glycemic Target of 70 mg/dL	Percent of time is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to Week 12
Percent of Time Spent in Hypoglycemia Below 50 mg/dL	Percent of time is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to Week 12
Change in Average Blood Glucose	Change in average blood glucose is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to 12 weeks
Change in the Blood Glucose Standard Deviation	Change in the blood glucose standard deviation is calculated from data collected from the continuous glucose monitor worn by participants. T1DM participants were instructed in the use of a continuous glucose monitor (CGM) for the monitoring of glycemia during the study. Participants were shown how to upload CGM data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to 12 weeks
Change in Average Total Daily Dose of Insulin	Average Total Daily Dose of Insulin is calculated from data collected from the the use of an insulin pump by participants. T1DM participants were instructed in the use of an insulin pump for the adminsitration of insulin during the study. Instructions included administering all insulin via insulin pump and recording all carbohydrates consumed into the insulin pump. T1DM participants were instructed how to upload insulin pump data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to 12 weeks
Change in Average Bolus Amount of Insulin Per Day	Average bolus amount of Insulin per day is calculated from data collected from the the use of an insulin pump by participants. T1DM participants were instructed in the use of an insulin pump for the adminsitration of insulin during the study. Instructions included administering all insulin via insulin pump and recording all carbohydrates consumed into the insulin pump. T1DM participants were instructed how to upload insulin pump data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to 12 weeks
Change in Average Basal Amount of Insulin Per Day	Average Basal Amount of Insulin Per Day is calculated from data collected from the the use of an insulin pump by participants. T1DM participants were instructed in the use of an insulin pump for the adminsitration of insulin during the study. Instructions included administering all insulin via insulin pump and recording all carbohydrates consumed into the insulin pump. T1DM participants were instructed how to upload insulin pump data into a HIPAA and FDA-compliant cloud-based, data-integration platform for analysis.	Baseline to 12 weeks
Change in Low Density Lipoprotein Particle Number	The number of Low Density Lipoprotein Particles (LDL-P) is directly measured using nuclear magnetic resonance (NMR) spectroscopy.	Baseline to 12 weeks
Change in High Density Lipoprotein Particle Number	The number of High Density Lipoprotein Particles (HDL-P) is directly measured using nuclear magnetic resonance (NMR) spectroscopy.	Baseline to 12 weeks
Change in Small Low Density Lipoprotein Particle Number	The number of Small Low Density Lipoprotein Particles (LDL-P) is directly measured using nuclear magnetic resonance (NMR) spectroscopy.	Baseline to 12 weeks
Change in Low Density Lipoprotein Size	The size of Low Density Lipoprotein Particles (LDL-P) is directly measured using nuclear magnetic resonance (NMR) spectroscopy.	Baseline to 12 weeks
Change in Concentration of Serum Ketones (Beta-hydroxybutyrate)	Change is measured by difference in concentration of serum ketones (beta-hydroxybutyrate)	Baseline to 12 weeks
Change in Score of Pediatric Quality of Life Inventory (PedsQL) Diabetes Module	The PedsQL 3.0 Teen Report (ages 13-18) is composed of 28 items. Item scaling is a 5-point scale from 0 (never) to 4 (almost always). The total possible range of scores 0-112 Higher scores indicate higher quality of life.	Baseline to week 12
Change in Diabetes Burden as Measured by the Problem Areas in Diabetes: Teen Version (PAID-T) Report	Diabetes burden was measured using the Problem Areas in Diabetes (PAID-T) parent-report, a measure of how bothersome day-to-day problems are for adolescents with type 1 diabetes. The he PAID-T is a 26 item measure scored on a likert scale from one-to-six with a total possible scale score ranging from 26-156. A lower score represents less burden.	Baseline to week 12

Collaborators and Investigators

• Sponsor: Vanderbilt University Medical Center
• Investigators: Study Director: Justin M Gregory, MD, MSCI, Vanderbilt University Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): November 18, 2019
• Primary Completion (Actual): June 30, 2021
• Study Completion (Actual): June 30, 2021

Study Registration Dates

• First Submitted: June 21, 2019
• First Submitted That Met QC Criteria: June 21, 2019
• First Posted (Actual): June 25, 2019

Study Record Updates

• Last Update Posted (Actual): May 8, 2023
• Last Update Submitted That Met QC Criteria: June 23, 2022
• Last Verified: June 1, 2022

More Information

Terms related to this study

• Keywords: Low Carbohydrate Diet; Standard Carbohydrate Diet
• 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: 190851

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No