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Effect of a Dietary Intervention on Insulin Requirements in Type 1 Diabetes (T1D)

Primary Purpose

Diabetes Mellitus, Type 1

Status
Recruiting
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Dietary intervention
Dietary intervention
Sponsored by
Physicians Committee for Responsible Medicine
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Diabetes Mellitus, Type 1

Eligibility Criteria

18 Years - undefined (Adult, Older Adult)All SexesAccepts Healthy Volunteers

Inclusion criteria:

  1. Type 1 diabetes
  2. Men and women ≥ 18 years of age
  3. Stable insulin regimen for past 3 months

Exclusion criteria:

  1. Type 2 or gestational diabetes
  2. Body mass index ≥ 40 kg/m2
  3. HbA1c ≥ 12.0%
  4. Smoking or drug abuse during the past six months
  5. Alcohol consumption of more than 2 drinks per day or the equivalent, episodic increased drinking (e.g., more than 2 drinks per day on weekends), or a history of alcohol abuse or dependency followed by any current use
  6. Unstable medical or psychiatric illness
  7. Already following a low-fat vegan diet
  8. Pregnant or breastfeeding, or plans of pregnancy within the study period
  9. Lack of English fluency
  10. Unable or unwilling to participate in all components of the study
  11. Evidence of an eating disorder

Sites / Locations

  • Physicians Committee for Responsible MedicineRecruiting

Arms of the Study

Arm 1

Arm 2

Arm Type

Active Comparator

Active Comparator

Arm Label

Low-fat, vegan diet

Portion-controlled diet

Arm Description

For a 12-week period, participants will be asked to follow a low-fat, vegan diet which consists of whole grains, vegetables, legumes, and fruits, with no restriction on energy intake. Animal products and added oils will be excluded. In choosing grain products and starchy vegetables (e.g., bread, potatoes), participants will be encouraged to select those retaining their natural fiber and having a glycemic index <70, using tables standardized to a value of 100 for glucose.

For a 12-week period, participants will be asked to follow a portion-controlled diet that is compliant with American Diabetes Association (ADA) guidelines. This diet will include individualized diet plans that reduce daily energy intake by 500-1,000 kcal for overweight (body mass index > 25 kg/m2) participants and keep carbohydrate intake reasonably stable over time. It will derive 15-20% from protein, <7% saturated fat, 60-70% carbohydrate and monounsaturated fats and ≤200 mg/day of cholesterol/day.

Outcomes

Primary Outcome Measures

Total Insulin Dose
A sum of basal and bolus insulin units (U) injected per day. An average from three (3) days (two (2) workdays and one (1) weekend day) will be utilized.
Glycemic Control
Hemoglobin A1c (HbA1c), an index of glycemic control, will be utilized.
Glycemic Variability
Glycemic variability will be assessed through use of a continuous glucose monitoring (CGM) system that will measure the concentration of glucose in the interstitial fluid. Participants will be instructed to wear a CGM (Dexcom g6 Platinum CGM System with an enhanced algorithm, software 505, Dexcom, Inc.) and record its readings at preset increments (after an overnight fast, before each meal, 2 hours after each meal, and before going to bed) daily. Participants will be prompted to submit CGM data to investigators on a weekly basis.
24-hour Carbohydrate to Insulin Ratio
Calculated as the total number of grams (g) of dietary carbohydrate to total units (U) of insulin administered.

Secondary Outcome Measures

Body Weight
Change in body weight measured on a calibrated scale.
Concentration of Plasma Lipids
Change in plasma cholesterol & triglycerides.
High-sensitivity C-reactive Protein (hs-CRP)
Implemented as a biomarker for absolute cardiovascular disease risk prediction.
Tumor necrosis factor - α (TNF-α)
Implemented to assess levels of systemic inflammation.
Interleukin (IL) - 1 (IL-1) and interleukin-6 (IL-6)
Implemented to assess levels of systemic inflammation.

Full Information

First Posted
June 21, 2021
Last Updated
April 18, 2022
Sponsor
Physicians Committee for Responsible Medicine
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1. Study Identification

Unique Protocol Identification Number
NCT04944316
Brief Title
Effect of a Dietary Intervention on Insulin Requirements in Type 1 Diabetes
Acronym
T1D
Official Title
Physicians Committee for Responsible Medicine - A Randomized, Controlled Study of the Effect of a Low-fat, Plant-based Diet on Insulin Requirements in Individuals With Type 1 Diabetes
Study Type
Interventional

2. Study Status

Record Verification Date
April 2022
Overall Recruitment Status
Recruiting
Study Start Date
January 19, 2022 (Actual)
Primary Completion Date
December 30, 2022 (Anticipated)
Study Completion Date
December 31, 2022 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Physicians Committee for Responsible Medicine

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
Yes

5. Study Description

Brief Summary
The purpose of this study is to compare the effects of a low-fat, plant-based dietary intervention and a portion-controlled dietary intervention (compliant with current American Diabetes Association (ADA) guidelines) on the management of type 1 diabetes in adults. The primary outcome measure of this study is insulin requirements (measured as the total daily dose (TDD) of insulin or basal and bolus insulin units injected per day). The study duration is 12 weeks.
Detailed Description
Type 1 diabetes is a chronic autoimmune disorder characterized by loss of β-cell mass and function in the pancreas, leading to reduced secretion of insulin and hyperglycemia. The management of type 1 diabetes requires the administration of exogeneous insulin. Total daily dose (TDD) of insulin, a measure of the total amount of exogeneous insulin utilized per day, can be affected by multiple factors including insulin resistance, carbohydrate intake, body weight, and body composition. While the pathogenesis of type 1 diabetes and type 2 diabetes differ, a low-fat, plant-based diet has been shown to reduce insulin resistance, reduce body weight, improve body composition, and improve glycemic control in individuals with type 2 diabetes. A low-fat, plant-based diet has also been shown to improve β-cell function in individuals who are overweight. This finding is consistent with other research that shows that therapies that reduce body fat, or modify the distribution of body fat, improve β-cell function and glucose homeostasis. To date, a low-fat, plant-based diet has never been adequately tested in adults with type 1 diabetes. The purpose of this study is to compare the effects of low-fat, plant-based dietary intervention and a portion-controlled dietary intervention (compliant with current American Diabetes Association (ADA) guidelines) on insulin requirements in adults with type 1 diabetes. Using a parallel group design, participants with type 1 diabetes will be randomly assigned to follow a low-fat, plant-based diet or a portion-controlled diet (compliant with current ADA guidelines) for 12 weeks. The principal dependent measures of this study are TDD of insulin, hemoglobin A1c (HbA1c), interstitial fluid glucose levels, and 24-hour carbohydrate: insulin ratio. Secondary and tertiary dependent measures include inflammatory biomarkers, blood lipids, body weight, diet quality, diet acceptability, and medication use. The investigators hypothesize that both the low-fat, plant-based dietary intervention and the portion-controlled dietary intervention will elicit changes in insulin requirements, HbA1c, variability in interstitial glucose levels, insulin sensitivity, and body weight in participants with type 1 diabetes. The investigators further hypothesize that the low-fat, plant-based dietary intervention will confer a more substantial effect on changes in insulin requirements, HbA1c, insulin sensitivity, variability in interstitial glucose levels, and body weight in participants with type 1 diabetes.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Diabetes Mellitus, Type 1

7. Study Design

Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
Care Provider
Allocation
Randomized
Enrollment
30 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
Low-fat, vegan diet
Arm Type
Active Comparator
Arm Description
For a 12-week period, participants will be asked to follow a low-fat, vegan diet which consists of whole grains, vegetables, legumes, and fruits, with no restriction on energy intake. Animal products and added oils will be excluded. In choosing grain products and starchy vegetables (e.g., bread, potatoes), participants will be encouraged to select those retaining their natural fiber and having a glycemic index <70, using tables standardized to a value of 100 for glucose.
Arm Title
Portion-controlled diet
Arm Type
Active Comparator
Arm Description
For a 12-week period, participants will be asked to follow a portion-controlled diet that is compliant with American Diabetes Association (ADA) guidelines. This diet will include individualized diet plans that reduce daily energy intake by 500-1,000 kcal for overweight (body mass index > 25 kg/m2) participants and keep carbohydrate intake reasonably stable over time. It will derive 15-20% from protein, <7% saturated fat, 60-70% carbohydrate and monounsaturated fats and ≤200 mg/day of cholesterol/day.
Intervention Type
Behavioral
Intervention Name(s)
Dietary intervention
Intervention Description
Low-fat, plant-based diet
Intervention Type
Behavioral
Intervention Name(s)
Dietary intervention
Intervention Description
Portion-controlled diet (compliant with ADA guidelines)
Primary Outcome Measure Information:
Title
Total Insulin Dose
Description
A sum of basal and bolus insulin units (U) injected per day. An average from three (3) days (two (2) workdays and one (1) weekend day) will be utilized.
Time Frame
Change from week 0 to week 12
Title
Glycemic Control
Description
Hemoglobin A1c (HbA1c), an index of glycemic control, will be utilized.
Time Frame
Change from week 0 to week 12
Title
Glycemic Variability
Description
Glycemic variability will be assessed through use of a continuous glucose monitoring (CGM) system that will measure the concentration of glucose in the interstitial fluid. Participants will be instructed to wear a CGM (Dexcom g6 Platinum CGM System with an enhanced algorithm, software 505, Dexcom, Inc.) and record its readings at preset increments (after an overnight fast, before each meal, 2 hours after each meal, and before going to bed) daily. Participants will be prompted to submit CGM data to investigators on a weekly basis.
Time Frame
Change from week 0 to week 12
Title
24-hour Carbohydrate to Insulin Ratio
Description
Calculated as the total number of grams (g) of dietary carbohydrate to total units (U) of insulin administered.
Time Frame
Change from week 0 to week 12
Secondary Outcome Measure Information:
Title
Body Weight
Description
Change in body weight measured on a calibrated scale.
Time Frame
Change from week 0 to week 12
Title
Concentration of Plasma Lipids
Description
Change in plasma cholesterol & triglycerides.
Time Frame
Change from week 0 to week 12
Title
High-sensitivity C-reactive Protein (hs-CRP)
Description
Implemented as a biomarker for absolute cardiovascular disease risk prediction.
Time Frame
Change from week 0 to week 12
Title
Tumor necrosis factor - α (TNF-α)
Description
Implemented to assess levels of systemic inflammation.
Time Frame
Change from week 0 to week 12
Title
Interleukin (IL) - 1 (IL-1) and interleukin-6 (IL-6)
Description
Implemented to assess levels of systemic inflammation.
Time Frame
Change from week 0 to week 12
Other Pre-specified Outcome Measures:
Title
Medication Use
Description
Participants will be asked to report changes in their medication use.
Time Frame
Change from week 0 to week 12
Title
Diet Quality
Description
Dietary intake will be assessed using 3-day dietary records. Participants will be instructed to record all dietary intake for 3 consecutive days, including 2 weekdays and 1 weekend day. Records will be analyzed using Nutrition Data System for Research software version 2018, developed by the Nutrition Coordinating Center (NCC), University of Minnesota, Minneapolis, MN, US.
Time Frame
Change from week 0 to week 12
Title
Diet Acceptability
Description
The Food Acceptability Questionnaire (FAQ), a self-reported measure, will be implemented to assess the subjective responses (palatability; satisfaction; ease of preparation; financial feasibility; and perceived physical benefits) of participants to their baseline diets and the intervention diet. The FAQ has twelve (12) total questions. Eleven (11) of the questions are scored on a Likert scale (1-7) and one (1) unscored question (physical benefits) will prompt the participant to "check all that apply." A higher FAQ score corresponds with a more positive subjective response.
Time Frame
Change from week 0 to week 12

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion criteria: Type 1 diabetes Men and women ≥ 18 years of age Stable insulin regimen for past 3 months Exclusion criteria: Type 2 or gestational diabetes Body mass index ≥ 40 kg/m2 HbA1c ≥ 12.0% Smoking or drug abuse during the past six months Alcohol consumption of more than 2 drinks per day or the equivalent, episodic increased drinking (e.g., more than 2 drinks per day on weekends), or a history of alcohol abuse or dependency followed by any current use Unstable medical or psychiatric illness Already following a low-fat vegan diet Pregnant or breastfeeding, or plans of pregnancy within the study period Lack of English fluency Unable or unwilling to participate in all components of the study Evidence of an eating disorder
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Tatiana Znayenko-Miller, MS
Phone
202-527-7317
Email
tznayenkomiller@pcrm.org
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Hana Kahleova, MD, PhD
Organizational Affiliation
Physicians Committee for Responsible Medicine
Official's Role
Principal Investigator
Facility Information:
Facility Name
Physicians Committee for Responsible Medicine
City
Washington
State/Province
District of Columbia
ZIP/Postal Code
20016
Country
United States
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Tatiana Znayenko-Miller, MS
Email
tznayenkomiller@pcrm.org

12. IPD Sharing Statement

Citations:
PubMed Identifier
18175767
Citation
Riccardi G, Rivellese AA, Giacco R. Role of glycemic index and glycemic load in the healthy state, in prediabetes, and in diabetes. Am J Clin Nutr. 2008 Jan;87(1):269S-274S. doi: 10.1093/ajcn/87.1.269S.
Results Reference
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PubMed Identifier
1659172
Citation
Anderson JW, Zeigler JA, Deakins DA, Floore TL, Dillon DW, Wood CL, Oeltgen PR, Whitley RJ. Metabolic effects of high-carbohydrate, high-fiber diets for insulin-dependent diabetic individuals. Am J Clin Nutr. 1991 Nov;54(5):936-43. doi: 10.1093/ajcn/54.5.936.
Results Reference
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PubMed Identifier
29382975
Citation
American Diabetes Association. Standards of Medical Care in Diabetes-2018 Abridged for Primary Care Providers. Clin Diabetes. 2018 Jan;36(1):14-37. doi: 10.2337/cd17-0119. No abstract available.
Results Reference
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PubMed Identifier
12830019
Citation
Pastors JG, Franz MJ, Warshaw H, Daly A, Arnold MS. How effective is medical nutrition therapy in diabetes care? J Am Diet Assoc. 2003 Jul;103(7):827-31. doi: 10.1016/s0002-8223(03)00466-8. No abstract available.
Results Reference
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PubMed Identifier
12900694
Citation
Craig CL, Marshall AL, Sjostrom M, Bauman AE, Booth ML, Ainsworth BE, Pratt M, Ekelund U, Yngve A, Sallis JF, Oja P. International physical activity questionnaire: 12-country reliability and validity. Med Sci Sports Exerc. 2003 Aug;35(8):1381-95. doi: 10.1249/01.MSS.0000078924.61453.FB.
Results Reference
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PubMed Identifier
11815483
Citation
Mari A, Tura A, Gastaldelli A, Ferrannini E. Assessing insulin secretion by modeling in multiple-meal tests: role of potentiation. Diabetes. 2002 Feb;51 Suppl 1:S221-6. doi: 10.2337/diabetes.51.2007.s221.
Results Reference
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PubMed Identifier
22673566
Citation
Kahleova H, Mari A, Nofrate V, Matoulek M, Kazdova L, Hill M, Pelikanova T. Improvement in beta-cell function after diet-induced weight loss is associated with decrease in pancreatic polypeptide in subjects with type 2 diabetes. J Diabetes Complications. 2012 Sep-Oct;26(5):442-9. doi: 10.1016/j.jdiacomp.2012.05.003. Epub 2012 Jun 4.
Results Reference
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PubMed Identifier
12778049
Citation
American Dietetic Association; Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets. J Am Diet Assoc. 2003 Jun;103(6):748-65. doi: 10.1053/jada.2003.50142.
Results Reference
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PubMed Identifier
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Citation
Barnard ND, Akhtar A, Nicholson A. Factors that facilitate compliance to lower fat intake. Arch Fam Med. 1995 Feb;4(2):153-8. doi: 10.1001/archfami.4.2.153.
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Becker MH. The health belief model and personal health behavior. Health Educ Monogr. 1974;2:324-508.
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Barnard N, Scialli AR, Bertron P, Hurlock D, Edmonds K. Acceptability of a Therapeutic Low-Fat, Vegan Diet in Premenopausal Women. J Nutr Educ. 2000;32(6):314-319. doi:10.1016/S0022-3182(00)70590-5
Results Reference
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Effect of a Dietary Intervention on Insulin Requirements in Type 1 Diabetes

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