The Dietary Education Trial in Carbohydrate Counting (DIET-CARB Study in Type 1 Diabetes

The Dietary Education Trial in Carbohydrate Counting (DIET-CARB Study): A Randomized, Parallel, Open-label, Intervention Study Comparing Different Approaches to Dietary Self-management in Patients With Type 1 Diabetes

The study is designed to evaluate two different dietitian-led self-management approaches in carbohydrate counting compared to routine dietary care (control) on glycaemic control in adult patients with type 1 diabetes:

1. The basic carbohydrate counting concept aims at improving carbohydrate counting accuracy and day-to-day consistency of carbohydrate intake (the BCC intervention)
2. The advanced carbohydrate counting concept aims at improving prandial insulin dose accuracy using an automated bolus calculator (the ABC-ACC intervention)

The main hypothesis is that structured training and education in either the BCC concept or the ABC-ACC concept will reduce HbA1c or the average glucose variability more than routine dietary education.

Study Overview

• Status: Completed
• Conditions: Glucose Metabolism Disorders; Type1diabetes; Type1 Diabetes Mellitus
• Intervention / Treatment: Behavioral: BCC intervention; Behavioral: ABC-ACC intervention; Behavioral: Standard dietary education

Detailed Description

The current study is a randomized controlled trial with a parallel-group design. A total of 231 patients will be enrolled in the trial. Participants will be randomized to one of three arms: 1) Basic carbohydrate counting (BCC), 2) Advanced carbohydrate counting with an automated bolus calculator (ABC-ACC), or 3) Standard dietary care.

The primary objective is to evaluate the six months effects of education in the BCC concept and the ABC-ACC concept compared to standard dietary care on glycaemic control as assessed by HbA1c or MAGE (mean amplitude of glycaemic excursions).

• Study Type: Interventional
• Enrollment (Actual): 63
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Gentofte, Denmark, DK-2820
    • Steno Diabetes Center Copenhagen

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Type 1 diabetes
• Diabetes duration; >12 months
• HbA1c of 53-97 mmol/mol
• Multiple daily insulin injection therapy
• Provided voluntary written informed consent

Exclusion Criteria:

• Practicing carbohydrate counting, as judged by the investigator
• Participated in a BCC group program within the last two years
• Use of insulin pump, or plans of having an insulin pump within the study period
• Fixed dose of rapid acting insulin therapy for meals
• Split-mixed insulin therapy
• Use of open CGM
• Use of Freestyle Libre
• Use of an automated bolus calculator
• Gastroparesis
• Pregnancy or breastfeeding, or plans of pregnancy within the study period
• Low daily intake of carbohydrates (defined as below 25 E% or 100 g/day), as judged by the investigator
• Uncontrolled medical issues, as judged by the investigator or a medical expert
• Concomitant participation in other clinical studies
• Unable to understand the informed consent and the study procedures

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: BCC intervention; The BCC program consists of three group sessions and is delivered by two trained dietitians. In addition to the BCC program, the participants receive regular medical care in the diabetes clinic	Behavioral: BCC intervention; Structured training and education i basic carbohydrate counting principles; Other Names: Basic carbohydrate counting
Experimental: ABC-ACC intervention; The ABC-ACC program consists of one group session and two individual follow-up sessions and is delivered by trained dietitians with supervision by a medical doctor. In addition to the ABC-ACC program, the participants receive regular medical care in the diabetes clinic	Behavioral: ABC-ACC intervention; Structured training and education i advanced carbohydrate counting principles including the use of a automated bolus calculator carbohydrate; Other Names: Advanced carbohydrate counting with a bolus calculator
Active Comparator: Standard dietary education; The routine outpatient dietary care consists of three individual consultations delivered by a trained dietitian. The individual guidance is based on the overall treatment goal(s), the defined personal dietary goals for behavioral change which will be in accordance with the patient's needs and preferences. In addition to the dietary counselling, the participants receive regular medical care in the diabetes clinic	Behavioral: Standard dietary education; Personalized individual dietary counselling based on overall meal planning, dietary guidelines and the patient's need and preferences; Other Names: Routine dietary care

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HbA1c	mmol/mol	Baseline, 6 months
Change in mean amplitude of glycaemic excursions (MAGE)	mmol/l	Baseline, 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HbA1c	mmol/mol	12 months
Change in body weight	kg	Baseline, 6 months, 12 months
Change in low-density lipoprotein cholesterol (LDL-C)	mmol/l	Baseline, 6 months, 12 months
Change in high-density cholesterol (HDL-C)	mmol/l	Baseline, 6 months, 12 months
Change in total cholesterol (TC)	mmol/l	Baseline, 6 months, 12 months
Change in free fatty acids (FFA)	mmol/l	Baseline, 6 months, 12 months
Change in triglycerides (TG)	mmol/l	Baseline, 6 months, 12 months
Change in diastolic blood pressure	mm Hg	Baseline, 6 months, 12 months
Change in systolic blood pressure	mm Hg	Baseline, 6 months, 12 months
Change in waist circumference	cm	Baseline, 6 months, 12 months
Change in hip circumference	cm	Baseline, 6 months, 12 months
Change in total fat free mass	gram	Baseline, 6 months
Change in total fat mass	gram	Baseline, 6 months
Change in standard deviation of mean plasma glucose	mmol/l	Baseline, 6 months
Change in total energy intake	kJ/day	Baseline, 6 months
Change in dietary intake of carbohydrates	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in dietary intake of total fat	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in dietary intake of saturated fatty acids (SFA)	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in dietary intake of monounsaturated fatty acids (MUFA)	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in dietary intake of polyunsaturated fatty acids (PUFA)	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in dietary intake of protein	gram/day or percent of total energy (E%)	Baseline, 6 months
Change in intake of dietary fibre	gram/day or g/MJ	Baseline, 6 months
Change in time in range (3.9-10.0 mmol/l)	Percent (%)	Baseline, 6 months
Changes in % time spent in hypoglycaemia (<3.9 mmol/l)	Percent (%)	Baseline, 6 months
Change % time spent in hyperglycaemia (e.g. >11.1 mmol/l)	Percent (%)	Baseline, 6 months
Change in mathematical literacy	Total score or percent (%)	Baseline, 6 months, 12 months
Change in carbohydrate estimation accuracy	Total score or percent (%)	Baseline, 6 months, 12 months
Change in diet-related quality of life	Total score or percent (%)	Baseline, 6 months, 12 months
Change in perceived competences in diabetes	Total score or percent (%)	Baseline, 6 months, 12 months
Change in degree of autonomy-supportive dietitian	Total score or percent (%)	Baseline, 6 months, 12 months
Change in dietary intake of added sugar	gram/day or percent of total energy (E%)	Baseline, 6 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in physical activity level	Total score or percent (%)	Baseline, 6 months, 12 months
Change in urinary biomarkers of carbohydrate intake	Percent (%)	Baseline, 6 months

Collaborators and Investigators

• Sponsor: Steno Diabetes Center Copenhagen
• Collaborators: University of Copenhagen
• Investigators: Principal Investigator: Bettina Ewers, MSc, Steno Diabetes Center Copenhagen

Publications and helpful links

General Publications

• Ewers B, Vilsboll T, Andersen HU, Bruun JM. The dietary education trial in carbohydrate counting (DIET-CARB Study): study protocol for a randomised, parallel, open-label, intervention study comparing different approaches to dietary self-management in patients with type 1 diabetes. BMJ Open. 2019 Sep 3;9(9):e029859. doi: 10.1136/bmjopen-2019-029859.

Study record dates

Study Major Dates

• Study Start (Actual): September 28, 2018
• Primary Completion (Actual): August 17, 2022
• Study Completion (Actual): August 17, 2022

Study Registration Dates

• First Submitted: July 19, 2018
• First Submitted That Met QC Criteria: August 7, 2018
• First Posted (Actual): August 9, 2018

Study Record Updates

• Last Update Posted (Actual): January 5, 2024
• Last Update Submitted That Met QC Criteria: January 2, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Keywords: Diet; Carbohydrates; Carbohydrate counting; Basic carbohydrate counting; Advanced carbohydrate counting
• Additional Relevant MeSH Terms: Immune System Diseases; Autoimmune Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1; Metabolic Diseases; Glucose Metabolism Disorders
• Other Study ID Numbers: H-18014897

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