Carbohydrates Under Target for Type 1 Diabetes Management

Overview

Recently there has been an increased interest in limiting intake of carbohydrates (CHO) for improving long term health. While healthcare professionals (HCPs) are sometimes reluctant to limit the CHO intake due to the lack of information related to safety issues, low CHO diets are increasing in popularity amongst both people with and without diabetes. One of these diets, the very low CHO high fat diet (VLCHF) raises concern on its impact on the lipid profile, liver, response to glucagon, and insulin dose adjustments when adopting it in the context of type 1 diabetes (T1D). The investigators recently conducted a series of interviews with people with diabetes following a VLCHF diet (Brazeau et al. Manuscript in preparation) to inquire on their reasons for adopting VLCHF as well as challenges they faced. The main reasons to initiate the diet were to limit blood glucose fluctuations and reduce medication. An issue that was frequently mentioned during the interviews was the lack of support from HCPs which often leads to not discussing it with said HCP. This is an important source of concern that can lead to additional safety issues. Our goal is to provide information regarding the safety of a VLCHF diet for T1D and the individualized insulin adjustments required.

The investigators aim to evaluate the changes in daily blood glucose fluctuations after 6 weeks of a VLCHF diet, to monitor the changes in the insulin dosing and to measure impact on lipid profiles, response to glucagon, and liver function.

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Crossover Assignment
    • Primary Purpose: Treatment
    • Masking: None (Open Label)
  • Study Primary Completion Date: May 2021

Interventions

  • Other: Control Diet
    • Participants will be provided with a two-week menu to be consumed 3 times for each intervention, for a total of 6 weeks per intervention. For the Control diet, the diet will provide 50% of energy from CHO, 15% from protein, and 35% from lipids. Menu will be adapted to the participant’s food preferences and usual caloric intake by a dietitian. Participants will be asked to limit their alcohol intake in both interventions. During this phase, participants will also have to wear a pedometer and use the Pezio: Achieve the Guidelines! mobile application to help the research assistant track their daily steps remotely.
  • Other: VLCHF Diet
    • Participants will be provided with a two-week menu to be consumed 3 times for each intervention, for a total of 6 weeks per intervention. For the Experimental diet, the diet will provide 10% of energy from CHO, 15% from protein, and 75% from lipids. During the Experimental diet, participants will be provided with a multivitamin to reduce risk of deficiencies due to restrictions on fruits and grain products. Menu will be adapted to the participant’s food preferences and usual caloric intake by a dietitian. Participants will be asked to limit their alcohol intake in both interventions. During this phase, participants will also have to wear a pedometer and use the Pezio: Achieve the Guidelines! mobile application to help the research assistant track their daily steps remotely.

Arms, Groups and Cohorts

  • Experimental: Control diet followed by VLCHF diet
    • Phase 1 (1 to 3 weeks): Insulin dose optimization with usual diet Phase 2 (6 weeks): Control diet (50% of energy from carbohydrates) Phase 3 (4 weeks): Washout period Phase 4 (6 weeks): VLCHF diet (10% of energy from carbohydrates)
  • Experimental: VLCHF diet followed by Control diet
    • Phase 1 (1 to 3 weeks): Insulin dose optimization with usual diet Phase 2 (6 weeks): VLCHF diet (10% of energy from carbohydrates) Phase 3 (4 weeks): Washout period Phase 4 (6 weeks): Control diet (50% of energy from carbohydrates)

Clinical Trial Outcome Measures

Primary Measures

  • Daily blood glucose standard deviation
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring

Secondary Measures

  • Percentage of time-in-target (range of 4-10 mmol/L)
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring
  • Coefficient of glucose variation
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring
  • Mean sensor glucose values (mmol/L)
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring
  • Glucose area under the curve for 2 hours post-prandial
    • Time Frame: First and last week of each intervention diet
    • Using continuous glucose monitoring
  • Number of hypoglycemia episodes necessitating treatment recorded
    • Time Frame: Over the 6 weeks of each intervention diet
    • Recorded by participants on hypoglycemia journal
  • Percentage of time spent in hypoglycemia ranges (< 4 mmol/L and < 3 mmol/L)
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring
  • Percentage of time spent in hyperglycemia ranges (>10 mmol/L and > 15 mmol/L)
    • Time Frame: Over the 6 weeks of each intervention diet
    • Using continuous glucose monitoring
  • Daily insulin adjustments required to maintain safe blood glucose
    • Time Frame: Over the 6 weeks of each intervention diet
    • Adjustments (basal and prandial) to avoid hypoglycemia (blood glucose < 4 mmol/L) and hyperglycemia (blood glucose > 15 mmol/L)
  • Short-term effects on anthropometric parameters : weight (kg) and height (cm)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Weight and height will be combined to report BMI (kg/m^2)
  • Short-term effects on anthropometric parameters : waist circumference (cm)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Calculated using the average of 3 measures
  • Short-term effects on blood lipid profiles
    • Time Frame: Following the 6 weeks of each intervention diet
    • Total cholesterol, HDL-chol, and LDL-chol, triglycerides, Apo-B and Apo-A
  • Short-term effects on body composition (lean and fat mass)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Measured by DEXA (Dual-Energy X-ray Absorptiometry)
  • Short-term effects on inflammatory parameters
    • Time Frame: Following the 6 weeks of each intervention diet
    • Plasma lipopolysaccharide (LPS), interleukine 6 (IL-6), monocyte chemoattractant protein-1 MCP-1)
  • Short-term effects on oxidative stress/redox parameters
    • Time Frame: Following the 6 weeks of each intervention diet
    • Total and reduced glutathione
  • Short-term effects on blood pressure
    • Time Frame: Following the 6 weeks of each intervention diet
    • Systolic and diastolic blood pressure
  • Short-term effects on liver function
    • Time Frame: Following the 6 weeks of each intervention diet
    • Aminotransferases, alkaline phosphatase, gamma-glutamyl transpeptidase, bilirubin, albumin
  • Short-term effects on resting metabolic rate
    • Time Frame: Following the 6 weeks of each intervention diet
    • After a 10-hour fast measured by indirect calorimetry
  • Short-term effects on liver proton density fat fraction by MRS (MRS-PDFF) (%)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Using hepatic fat imagery (MRI)
  • Short-term effects on mean liver PDFF
    • Time Frame: Following the 6 weeks of each intervention diet
    • Using hepatic fat imagery (MRI)
  • Short-term effects on total liver volume (mL)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Using hepatic fat imagery (MRI)
  • Short-term effects on total liver fat index (%.ml)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Using hepatic fat imagery (MRI)
  • Efficacy of glucagon in correcting hypoglycemia
    • Time Frame: Following the 6 weeks of each intervention diet
    • Time needed to reach a blood glucose > 4 mmol/L after glucagon treatment of an insulin-induced hypoglycemia reaching 4 mmol/L at 15, 20 and 30 min post glucagon administration, peak plasma glucose level two hours after administration, insulin, glucagon, ketone and free fatty acids levels.
  • Modulation of postprandial glycemic response (Standardized meal-tests)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Hunger, appetite and fullness scores, lat the following times (-20, 0, 15, 30, 60, 90, 120 and 180 min, with 0 min being the start of meal consumption)
  • Secretion of key gastrointestinal peptides (Standardized meal-tests)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Gastrointestinal peptides : levels of glucose, insulin glucagon, GLP-1, PYY and acylated ghrelin at the following times (-20, 0, 15, 30, 60, 90, 120 and 180 min, with 0 min being the start of meal consumption), as well as their corresponding kinetics including areas under the curve (AUC), peak values and nadirs.
  • Questionnaire of well-being (score)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Corresponding scores of questionnaire used to assess different quality of life aspects: well-being, fatigue, nausea, hunger, appetite, desire to eat.
  • Questionnaire of diet satisfaction (score)
    • Time Frame: Following the 6 weeks of each intervention diet
    • Corresponding scores of questionnaire used to assess different quality of life aspects: diet satisfaction, difficulty to follow the diet, difficulty for meal preparation.
  • Effects on physical activity (steps/day)
    • Time Frame: Over the 6 weeks of each intervention diet
    • Steps per day recorded with a pedometer (PedioRxD) and mobile application (baseline and during each intervention diet)

Participating in This Clinical Trial

Inclusion Criteria

  • Duration of Type 1 Diabetes > 12 months
  • On intensive insulin therapy for > 6 months
  • Own a smartphone or tablet to use two mobile applications : Keenoa and Piezo: Achieve the Guidelines!

Exclusion Criteria

  • Known gastroparesis (clinical diagnosis)
  • Advanced kidney disease (eGFR < 50 mL/min)
  • Known significant liver disease (e.g., cirrhosis, active hepatitis, liver transplantation)
  • Recent (< 6 months) major cardiovascular even (e.g. myocardial infarction, cerebrovascular accident, major revascularization, etc.)
  • Pregnancy (ongoing or planned in the next 6 months)
  • Breastfeeding
  • Severe hypoglycemia episodes or ketoacidosis in the 4 weeks prior to recruitment
  • Claustrophobia or presence of metal devices/implants in the body

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • McGill University
  • Provider of Information About this Clinical Study
    • Principal Investigator: Anne-Sophie Brazeau, Assistant Professor – McGill University
  • Overall Contact(s)
    • √Člisabeth Nguyen, B.Sc., 514-987-3238, elisabeth.nguyen@ircm.qc.ca

Clinical trials entries are delivered from the US National Institutes of Health and are not reviewed separately by this site. Please see the identifier information above for retrieving further details from the government database.

At TrialBulletin.com, we keep tabs on over 200,000 clinical trials in the US and abroad, using medical data supplied directly by the US National Institutes of Health. Please see the About and Contact page for details.