Randomized Controlled Trial Intervention With New Nordic DIet in Women With GestatiOnal Diabetes Mellitus: iNDIGO (iNDIGO)

The study evaluates whether the New Nordic Diet, compared to routine care, will improve glucose control, among women developing gestational diabetes mellitus during pregnancy.

Originally, a 10 wk intervention with qualified counseling on New Nordic Diet was planned, and effects on glycosylated haemoglobin A (HbA1c) at gestational age 37 weeks was planned as main outcome. Recruitment started in spring 2020 but had to be halted due to covid-19. Instead, we now conduct a more comprehensive version of the study, with a more intensive intervention consisting of distributed food bags plus dietary counselling for two weeks, and with continuous glucose monitoring during these two weeks to measure main outcome. This is more sensitive to small changes than is HbA1c. With this shorter and more intensive intervention we believe we can address our original hypothesis yet adjust to impacts of the covid-19 situation on the population and health care system.

Study Overview

• Status: Recruiting
• Conditions: Gestational Diabetes Mellitus
• Intervention / Treatment: Behavioral: New Nordic Diet; Other: Control

Detailed Description

Gestational diabetes mellitus (GDM) is associated with severe adverse outcomes for mother and newborn. Recently introduced Swedish guidelines on GDM diagnosis will at least double the prevalence of diagnosed women. The first line of treatment in GDM is diet and exercise treatment. Even so, there is a recognized knowledge gap as to what diet treatment is optimal. In routine care today, diagnosed women are provided by midwife with the same diet advice as patients with diabetes type 2 and these are broad and general. Only rarely are the diet advice provided by a dietician. In nutrition research, most evidence for health benefits of a diet has been demonstrated for the Mediterranean diet. Further, the New Nordic Diet (NND) was recently developed to mimic the Mediterranean diet yet builds on foods grown in the Nordic climate, thus focusing on gastronomical potential and sustainability. Interestingly, a diet intake in line with NND among Norwegian mothers was associated with lower risk for excessive pregnancy weight gain. In addition, associations have been shown between NND and lower risk for cardiovascular disease, obesity, inflammatory risk markers, serum lipids, colorectal cancer and total mortality. Hence, it seems likely that diet treatment with NND to women with GDM would be superior to routine care, but this has never been investigated. The main aim of the randomized controlled trial Intervention with new Nordic DIet in women with GestatiOnal diabetes mellitus (iNDIGO) is to test if the NND compared with usual care will improve glucose control in women with GDM. The iNDIGO study is a randomized parallel, single-blinded, controlled trial. In total, 50 women diagnosed with GDM are recruited and randomized to receive either a NND (intervention) or usual care (control) for 14 days. Participants receive a two-week menu and provided with food bags containing ingredients for dishes and foods to be used. Primary outcome is glycemic control (specifically time in target) measured using continuous glucose monitoring. Compliance to the dietary intervention will be tested using known dietary biomarkers and adherence questionnaires. Maternal socio-demographic and clinical data, biological samples, dietary intake and physical activity will be collected at enrollment and at the end of intervention (30-32 weeks' gestation).

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Anna Winkvist, PhD; Phone Number: 46-31-7863728; Email: anna.winkvist@nutrition.gu.se
• Study Contact Backup: Name: Therese Karlsson, PhD; Phone Number: 46-31-7863281; Email: therese.karlsson@gu.se

Study Locations

• Sweden
  • Göteborg, Sweden, S-41650
    • Recruiting
    • Antenatal Care
    • Contact: Verena Sengpiel, MD, PhD; Phone Number: 46-31-3421000; Email: verena.sengpiel@obgyn.gu.se
  • Stockholm, Sweden
    • Recruiting
    • Region Stockholm
    • Contact: Elisabeth Storck Lindholm, MD, PhD; Phone Number: 46725824652; Email: elisabeth.storck-lindholm@regionstockholm.se
  • Umeå, Sweden, 90185
    • Recruiting
    • Region Västerbotten
    • Contact: Julia Otten, MD, PhD; Phone Number: 46703341559; Email: julia.otten@umu.se

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• pregnant women with diagnosis of gestational diabetes in pregnancy wks 24-28.

Exclusion Criteria:

• multiple pregnancies
• not understanding/able to read Swedish or English
• unwilling to follow a dietary intervention
• manifest diabetes

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control; The control women receive diet advice according to usual care.	Other: Control; The control women receive diet advice according to usual care, which may be a short meeting with the regular midwife or a short meeting with a dietician. From the study, they will receive a gift certificate that can be used in grocery stores.
Experimental: Intervention; Women randomized to the New Nordic Diet meet the study dietician at week 30 for 1.5 hr of individual diet treatment according to the New Nordic Diet and a cognitive behavioral approach. The diet advice include evenly distributed meals over the day, foods low in fat and rich in fibre, 500 g fruit and vegetables daily, fish 2-3 times a week and keyhole foods. Participants will prepare their own food but are provided with recipes and food bags containing ingredients and foods to be consumed during the two-week intervention At gestational age 32 weeks, women meet with a dietitian and will be instructed to continue with the New Nordic Diet diet throughout pregnancy on their own.	Behavioral: New Nordic Diet; The New Nordic Diet conforms with the Nordic Nutrition Recommendations and incorporates environmental sustainability and planetary health. It includes rapeseed oil, whole grain bread, wild fish, seafood and game, potatoes, root vegetables, cabbages, Nordic fruits and berries. A two-week menu including all daily meals has been created to ensure dietary goals of the New Nordic Diet intervention: fish and shellfish intake ≥ 3 times/w (fatty fish at least once per week), ≥ 500 g fruit, berries, vegetables and legumes daily (legumes as main protein source at least twice per week), whole-grain cereal products, rapeseed oil for cooking/dressing and three table spoons of nuts and seeds per day.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time in Target at gestational week 32	Percentage of time in target (TIT) range 3.5-7.8 mmol/L measured with continuous glucose monitoring	At week 32 of pregnancy

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of pre-eclampsia	Diagnosis of pre-eclampsia	Up to delivery
Incidence of Caesarean sections	Delivery by caesarean sections	Up to delivery
Pregnancy weight gain	Weight gain during pregnancy from self-reported pre-pregnancy weight until delivery	Pre-pregnant weight up to delivery
Incidence of pregnancy-induced hypertension	Diagnosis of pregnancy-induced hypertension	Up to delivery
Prevalence of use of insulin/Metformin treatment	Decision to put woman on medication for the gestational diabetes, such as metformin or insulin	Up to delivery
Incidence of preterm delivery	Delivery before 37 completed weeks	Up to 37 completed weeks
Health-related quality of life	Health-related quality of life, calculated from questionnaire information from RAND-36	Up to 1 year postpartum
Incidence of LGA	Large-for-gestational age born infant	At delivery
Incidence of shoulder displacement	Shoulder displacement of newborn infant	At delivery
Apgar scores measurements	Apgar scores measured at 1, 5 and 10 minutes after delivery	At delivery
Additional measurements from continuous glucose monitoring at wk 32	mean glucose, CV, SD, MAGE, % time with values >7.8 mmol/L, % time with values <3.5 mmol/L, glucose in different time periods, and AUC	At gestational week 32
Additional measurements from continuous glucose monitoring at wk 36	mean glucose, CV, SD, MAGE, % time with values >7.8 mmol/L, % time with values <3.5 mmol/L, glucose in different time periods, and AUC	At gestational week 36
Incidence of macrosomia	Diagnosis of macrosomia in newborn infant	At delivery
Nutritional status	Nutritional status (vitamins and minerals) of mother during pregnancy	During pregnancy
Diet quality measuremen¨t	Diet intake quality of mother during pregnancy	Up to delivery

Collaborators and Investigators

• Sponsor: Göteborg University
• Collaborators: Swedish Council for Working Life and Social Research
• Investigators: Principal Investigator: Anna Winkvist, PhD, Göteborg University

Publications and helpful links

General Publications

• Karlsson T, Augustin H, Lindqvist M, Otten J, Petersson K, Storck-Lindholm E, Mogren I, Winkvist A. Effect of the New Nordic Diet compared with usual care on glucose control in gestational diabetes mellitus: Study protocol for the randomized controlled trial intervention with new Nordic DIet in women with GestatiOnal diabetes mellitus (iNDIGO). Contemp Clin Trials. 2022 Apr;115:106706. doi: 10.1016/j.cct.2022.106706. Epub 2022 Feb 12.

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2022
• Primary Completion (Estimated): December 1, 2024
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: October 28, 2019
• First Submitted That Met QC Criteria: November 18, 2019
• First Posted (Actual): November 19, 2019

Study Record Updates

• Last Update Posted (Actual): August 25, 2023
• Last Update Submitted That Met QC Criteria: August 24, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Diabetes Mellitus; Diabetes, Gestational
• Other Study ID Numbers: iNDIGO2018-00483

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