Cut Down on Carbohydrate in the Dietary Therapy of Type 2 Diabetes - The Meal Box Study — CutDM-MealBox  

Overweight and Obesity Clinical Trial

Official title: Cut Down on Carbohydrate in the Dietary Therapy of Type 2 Diabetes Mellitus - The Meal Box Study

Status Active, not recruiting

Clinical Trial Summary

The cornerstone in the initial treatment of type 2 diabetes (T2D) is lifestyle modification, involving-among other things-a healthy diet. However, scientific evidence regarding optimal nutrition therapy for patients with T2D is insufficient. This clinical study will examine the effect of a carbohydrate-reduced high-protein (CRHP) diet compared to a conventional diabetes (CD) diet for 12 months on metabolic function and body weight in patients with T2D. The hypothesis of the study is that the CRHP diet will improve metabolic control and the cardiovascular risk profile of patients with T2D to a greater extent than the CD diet. In particular, the expectation is that, compared with the CD diet, the CRHP diet will: - Reduce diurnal and postprandial glycemia measured by continuous glucose monitoring (CGM) and thereby facilitate a significant reduction of glycated hemoglobin (HbA1c) - Reduce body weight - Reduce ectopic fat deposition in the liver and the pancreas - Improve the blood lipid profile - Reduce or not affect blood pressure with no adverse effect on heart rate variability - Increase insulin sensitivity and secretion - Decrease inflammatory markers in the blood - Improve satiety - Reduce or not affect the need for antidiabetic, antihypertensive and/or lipid-lowering medications To reinforce the results and knowledge generated from the primary study, participants will be invited to partake in a 12-month follow-up period after the initial 12 months of intervention.

Clinical Trial Description

Methods: This is a 12-month investigator-initiated, randomized, controlled, open-label, superiority trial with two parallel groups. The study examines the effect of a CRHP diet (which is reduced in carbohydrate and increased in protein and fat) compared with a CD diet (which follows the currently recommended macronutrient intake for patients with T2D). The study will include 100 T2D patients with overweight or obesity. The macronutrient intake in the CD diet and the CRHP diet is 50 percentage of energy (E%) and 30 E% from carbohydrate, 17 E% and 30 E% from protein, and 33 E% and 40 E% from fat, respectively. The CD diet and the CRHP diet do not principally differ in the quality of carbohydrate, protein, and fat; they both comprise of nutritious, organic, and sustainable food items. Participants will be randomized in a 1:1 ratio to either the CD diet or the CRHP diet for 12 months. About 2/3 of the total calculated energy requirements on both diets will be delivered to the participants free of charge, as meal box solutions containing breakfast meals, snack meals, and dinner meals to optimize compliance and adherence to the assigned diet. After 12 months of intervention with meal boxes, a 12-month follow-up period will be initiated for participants who wish to continue to follow the diet they were allocated to at baseline. During the 12-month follow-up period there will be no provision of meal boxes. Assistance is provided to help the participants adhere to the diet by regular counselling with RCD's and support via the Liva app. The daily energy requirements for body weight maintenance will be calculated by multiplying resting energy expenditure using the Mifflin-St Jeor equation, with an estimated physical activity level (estimated by using a physical activity questionnaire at the beginning of the study). Based on the calculated daily energy requirements, participants will be divided into one of three energy level groups; in all groups, the amount of recommended total daily energy intake will exceed the amount required for weight maintenance and subjects will be instructed to consume the diets ad libitum until satiety is achieved. The dietary interventions are implemented under the guidance of registered clinical dietitians (RCDs) in a free-living setting without any instruction or requirement for weight loss or increased physical activity level. Participants will be instructed to eat until satiety is achieved and allowed to consume alcoholic beverages within the recommendations from the Danish Health Authorities. Dietary advice and counselling regarding food choices and preparation of food concerning the allocated diet, especially the self-prepared lunch meals and how to navigate at special occasions, will be given under the guidance of RCDs. Medication will be kept unchanged during the study, if possible. Rescue medication will be commenced if a HbA1c target of 58 mmol/mol is not reached after six months. If study participants obtain a HbA1c below 48 mmol/mol antidiabetic medication will still be kept constant. Diurnal urine samples, fasting blood samples, dietary records and questionnaire responses will be collected every third month of the study. In addition, at baseline and 12 months, participants will undergo a standardized test battery including magnetic resonance imaging (MRI) and spectroscopy (MRS) for measurement of abdominal subcutaneous and visceral adipose tissue, and ectopic fat in the liver and pancreas, dual X-ray absorptiometry (DXA) scans for body composition, handgrip strength and 30-second chair-stand for muscle strength, oral glucose tolerance test (OGTT), continuous glucose monitoring (CGM), Holter-recording, diurnal blood pressure measurement, and dietary records. Analysis: The primary outcome will be tested by a constrained linear mixed model (CLMM) with inherent baseline-adjustment. Diet group, time and their interaction will be included as fixed effects and participants as random effect. Secondary analyses will furthermore adjust for potential confounders in multivariate CLMMs. The secondary and explorative outcomes will be tested for significance using CLMMs for continuous data (including changes in blood lipid profiles, body weight and hepatic fat content) and Chi-squared tests for proportions (including proportion of the participants who increase their need for glucose lowering medications from baseline to 12 months). Secondary and explorative outcomes will be tested at a significance level at 0.05 without correction for multiplicity, but interpreted according to their secondary and explorative nature. Missing data will be evaluated in regards to whether they can be assumed to be missing at random, and in that case handled implicitly by maximum likelihood estimation in the CLMMs, which is the optimal approach statistically. Intention-to-treat analyses will be performed including all available data. Per protocol analyses of the diet groups will be performed to support the primary analysis. Ethics and dissemination: The National Committee on Health Research Ethics of the Capitol Region of Denmark has approved the trial (H-21057605). The study will be conducted in accordance with the Declaration of Helsinki II. Results will be submitted for publication in international peer-reviewed scientific journals, regardless of being positive, negative or inconclusive. ;

Related Conditions & MeSH terms

• Diabetes Mellitus
• Diabetes Mellitus Type 2
• Diabetes Mellitus, Type 2
• Overweight
• Overweight and Obesity

• NCT number: NCT05330247
• Study type: Interventional
• Source: Bispebjerg Hospital
• Status: Active, not recruiting
• Phase: N/A
• Start date: September 27, 2022
• Completion date: January 2026