Trial Review

Registering a new trial?

To achieve prospective registration, we recommend submitting your trial for registration at the same time as ethics submission.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12622001285741
Ethics application status
Approved
Date submitted
16/09/2022
Date registered
30/09/2022
Date last updated
30/09/2022
Date data sharing statement initially provided
30/09/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Investigating the impact of the healthy gut diet on the incidence of gestational diabetes
Scientific title
Investigating the impact of the healthy gut diet on the incidence of gestational diabetes: a multi-centre, randomised control trial in women with a prior history of gestational diabetes
Secondary ID [1] 307990 0
None
Universal Trial Number (UTN)
U1111-1282-6970
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gestational diabetes mellitus 327651 0
Condition category
Condition code
Reproductive Health and Childbirth 324739 324739 0 0
Antenatal care
Reproductive Health and Childbirth 324740 324740 0 0
Fetal medicine and complications of pregnancy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Intervention group will receive dietary counselling by an Accredited Practising Dietitian with the aim to modify dietary behaviour. The target behaviour will be to eat for gut health.
The intervention consists of:
- Initial dietary counselling, up to 40 minutes long, delivered via telehealth, within 1 - 2 weeks of enrolment
- Follow-up phone call 1 (approximately 2 weeks after the initial counselling session), maximum 20 minutes
- Follow- up phone call 2 (at 28 weeks gestation), maximum 20 minutes
- 1 - 3 text messages per week (motivational, informational, links to education material) from initial counselling session completion until 36 weeks gestation. Messages will be delivered via Telstra Messaging Service which does not monitor whether messages are received by participants.
- Electronic or hard copy of dietary education, workbook, recipes, shopping lists/checklists designed specifically for this study.
- Short videos via a social media page. Following the social media page is optional and this is provide to enhance participants' understanding of the Healthy Gut Diet should they choose to seek more information. The page can be viewed at participants' discretion. We will share recipes, Healthy Gut Tips (for example, cooking tips to increase resistance starch in foods or where to find fermented foods, or what foods are high in pre-probiotic fibre) and motivational messages (for example, other benefits of building a healthy gut such as long-term health or gut microbiome transfer to baby) as a post to the page (photo and content only post with written information) or as a short 'reel' (20 - 30 second video that summarises Healthy Gut recipes or 'tips'). We will not check participants' engagement with social media. These will be designed specifically for the study.

The dietary intervention will focus on increasing the quantity and diversity of whole plant based foods, supplemented with lean animal or plant-based protein options and limiting discretionary foods and foods high in saturated fat. The healthy gut diet focuses on fibre-rich foods (wholegrains, fruit, vegetables, legumes, nuts, seeds) with adequate amounts of lean meat, chicken, fish (or alternatives) and to support a healthy pregnancy in accordance with the Australian Dietary Guidelines. Participants will also be encouraged to include naturally fermented (shop-bought) foods such as yoghurt, sauerkraut and sourdough bread (for example).

The intervention workbook will provide a staged approach to increasing fibre-rich foods over 4 weeks to reduce discomfort associated with sudden increases to fibre intake.

Adherence to the intervention will be monitored at each appointment by checking against attendance and individualised, participant-set goals. This will also be checked in the final survey (at 36 weeks) with self-reported adherence to dietary behaviour goals and frequency of using resources sent via text messages and accessing social media content.
Intervention code [1] 324445 0
Lifestyle
Intervention code [2] 324446 0
Behaviour
Comparator / control treatment
Usual care (choice of antenatal model of care) will be sent an electronic colour handout of general healthy eating in pregnancy advice (based on the Australian Dietary Guidelines, available here https://www.eatforhealth.gov.au/sites/default/files/content/The%20Guidelines/n55h_healthy_eating_during_pregnancy.pdf) and a short, 4-minute video explaining general healthy eating during pregnancy. The video has been designed specifically for this study and will be sent as a link via email.
Control group
Active

Outcomes
Primary outcome [1] 332562 0
Diagnosis of gestational diabetes mellitus as recorded in medical records (diagnosis according to the Queensland Health Guideline available here: https://www.health.qld.gov.au/__data/assets/pdf_file/0022/950503/g-gdm.pdf)
Timepoint [1] 332562 0
At any stage during the pregnancy
Secondary outcome [1] 413926 0
Dietary intake (diversity and abundance of plant-foods as composite measure) assessed using baseline and 36 week short diet questionnaire (food frequency questionnaire) and 4 x 24 hour diet recalls submitted in trimester 2 and 3
Timepoint [1] 413926 0
Change from baseline to 36 week gestation measured using:
- Baseline food frequency questionnaire
- 24 hour diet recall x 2 in trimester 2
- 24 hour diet recall x 2 in trimester 3
- 36 weeks food frequency questionnaire
Secondary outcome [2] 413927 0
Gut Microbiota taxonomic markers (stool samples assessed using RNA shotgun sequencing by third party laboratory)
Timepoint [2] 413927 0
Change from baseline to 36 weeks gestation - assessed at baseline (prior to 18 weeks gestation and at 36 weeks) via self-collected stool samples posted directly to laboratory.
Secondary outcome [3] 413928 0
Gestational weight gain (within recommendations) measured according to pre-pregnancy weight (as recorded in pregnancy hand held record, usually self-reported) and weight at 36 weeks (self-reported or as per medical records), adjusted for gestation and reported continuously and categorically (inadequate, within recommendations, excessive) by pre-pregnancy body mass index and according to the Institute of Medicine's recommendations.
Timepoint [3] 413928 0
Pre-pregnancy to 36 weeks gestation
Secondary outcome [4] 413929 0
Pregnancy induced hypertension including preeclampsia as noted in medical records
Timepoint [4] 413929 0
At any stage during pregnancy
Secondary outcome [5] 413930 0
Preterm delivery (< 37 weeks) as reported in medical records
Timepoint [5] 413930 0
At birth
Secondary outcome [6] 414148 0
Polyhydraminos as reported in medical records
Timepoint [6] 414148 0
At any stage during pregnancy
Secondary outcome [7] 414149 0
Oedema as reported in medical records
Timepoint [7] 414149 0
At any stage during pregnancy
Secondary outcome [8] 414150 0
Large or small for gestational age as reported in medical records
Timepoint [8] 414150 0
At birth
Secondary outcome [9] 414151 0
Neonatal hypoglycaemia as reported in medical records
Timepoint [9] 414151 0
At birth
Secondary outcome [10] 414152 0
Mode of delivery as reported in medical records
Timepoint [10] 414152 0
At birth
Secondary outcome [11] 414153 0
Admission to special care nursery as reported in medical records
Timepoint [11] 414153 0
At birth
Secondary outcome [12] 414154 0
Birth Trauma as reported in medical records
Timepoint [12] 414154 0
At birth
Secondary outcome [13] 414155 0
Diet quality (Healthy Eating Index and Plant-based Index)
Timepoint [13] 414155 0
Change from baseline to 36 weeks gestation measured using:
- Baseline food frequency questionnaire
- 24 hour diet recall x 2 in trimester 2
- 24 hour diet recall x 2 in trimester 3
- 36 weeks food frequency questionnaire

Eligibility
Key inclusion criteria
Singleton pregnancy
<18 weeks gestation at enrolment
Birthing at study hospital
Prior history of gestational diabetes mellitus
Minimum age
18 Years
Maximum age
No limit
Sex
Females
Can healthy volunteers participate?
No
Key exclusion criteria
Current diagnosis of gestational diabetes mellitus.
Multiples pregnancy (twins/triplets)
Women will be ineligible if they have any other form of diabetes, cystic fibrosis, inflammatory bowel disease, bariatric surgery or a bowel disorder requiring restrictive diets, a diagnosed eating disorder, complex medical co-morbidities (for example kidney or heart disease). Additional exclusion criteria will be applied to women selected for gut microbiota testing (no anti or probiotics in the 3 months prior to enrolment).

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computed generated block randomisation (block sizes 6) stored in an excel spreadsheet
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Data analysis will be blinded
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
Comparisons between control and intervention groups for all outcome measures will be made using regression models that include the independent variable of group (treatment / control) and other potential confounders. Demographic outcomes will be described (frequencies and percents or mean and standard deviation) and used in regression analysis to adjust for confounding variables.
The primary outcome will be difference in gestational diabetes mellitus (GDM) diagnosis between groups.
The anticipated dietary intake difference between groups will be used to examine the effects on the gut microbiota. Microba will provide the full analysis of measures of gut microbiota (i.e. alpha and beta diversity, functional profiles). Analysis will include multiple regression models with an outcome of the change in microbiota (baseline to 36 weeks) and how this is associated with the change in diet. These models will adjust for baseline microbiota and other potential confounders, such as age, Gestational weight gain (GWG) and GDM treatment. The confounders for each model will be determined using causal diagrams, which transparently illustrate the model and assumptions.
Results will be reported using an intention-to-treat approach, so all women in the intervention arm will be included in the primary analysis. In a sensitivity analysis, a per protocol approach will be used - data from women who did not complete the three dietary counselling sessions will be excluded from this analysis. The intention-to-treat analysis gives the most realistic picture of the intervention in practice, whereas the per protocol analysis indicates the possible benefits if treatment adherence can be increased.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
2/01/2023
Actual
Date of last participant enrolment
Anticipated
30/04/2024
Actual
Date of last data collection
Anticipated
31/10/2024
Actual
Sample size
Target
140
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment hospital [1] 23166 0
Caboolture Hospital - Caboolture
Recruitment hospital [2] 23167 0
Redcliffe Hospital - Redcliffe
Recruitment postcode(s) [1] 38530 0
4510 - Caboolture
Recruitment postcode(s) [2] 38531 0
4020 - Redcliffe

Funding & Sponsors
Funding source category [1] 312253 0
Government body
Name [1] 312253 0
Queensland Department of Health - Health Innovation, Investment and Research Office
Country [1] 312253 0
Australia
Funding source category [2] 312255 0
University
Name [2] 312255 0
The University of Queensland
Country [2] 312255 0
Australia
Primary sponsor type
University
Name
The University of Queensland
Address
St Lucia
Brisbane, Queensland 4067
Country
Australia
Secondary sponsor category [1] 313795 0
None
Name [1] 313795 0
NA
Address [1] 313795 0
NA
Country [1] 313795 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311630 0
Metro North Human Research Ethics Committee (RBWH Committee A)
Ethics committee address [1] 311630 0
Level 7, Block 7
Royal Brisbane and Women’s Hospital
Butterfield Street, Herston QLD 4029
Ethics committee country [1] 311630 0
Australia
Date submitted for ethics approval [1] 311630 0
21/12/2021
Approval date [1] 311630 0
03/03/2022
Ethics approval number [1] 311630 0
HREC/2021/QRBW/82350

Summary
Brief summary
We will recruit pregnant women with a prior history of gestational diabetes mellitus (GDM) as part of a randomised control trial (RCT) to undertake the healthy gut dietary intervention (or control). We hypothesise that women who are provided dietitian counselling and education about a Healthy Gut Diet will improve their gut health (measured as the gut microbiome) and be less likely to develop GDM.
The primary outcome will the proportion of women developing GDM. Other outcomes include changes to gut microbiota, diet quality, gestational weight gain, and maternal and infant outcomes. The study sites are Redcliffe and Caboolture Hospitals.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 121778 0
Dr Nina Meloncelli
Address 121778 0
Metro North Allied Health
Office of the Chief Allied Health Practitioner
Level 13, Block 7
Royal Brisbane and Women's Hospital
Cnr Butterfield St and Bowen Bridge Rd
Herston QLD 4032
Country 121778 0
Australia
Phone 121778 0
+61 407695625
Fax 121778 0
Email 121778 0
[email protected]
Contact person for public queries
Name 121779 0
Nina Meloncelli
Address 121779 0
Metro North Allied Health
Office of the Chief Allied Health Practitioner
Level 13, Block 7
Royal Brisbane and Women's Hospital
Cnr Butterfield St and Bowen Bridge Rd
Herston QLD 4032
Country 121779 0
Australia
Phone 121779 0
+61 407695625
Fax 121779 0
Email 121779 0
[email protected]
Contact person for scientific queries
Name 121780 0
Nina Meloncelli
Address 121780 0
Metro North Allied Health
Office of the Chief Allied Health Practitioner
Level 13, Block 7
Royal Brisbane and Women's Hospital
Cnr Butterfield St and Bowen Bridge Rd
Herston QLD 4032
Country 121780 0
Australia
Phone 121780 0
+61 407695625
Fax 121780 0
Email 121780 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Non-identified, individual participant data of published results only.
When will data be available (start and end dates)?
Per university specifications - Not until 2025, available for 15 years after publication
Available to whom?
To university approved applicants
Available for what types of analyses?
Upon negotiation
How or where can data be obtained?
Application to the University of Queensland by first emailing the Principal Investigator ([email protected])


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbasePreventing Gestational Diabetes with a Healthy Gut Diet: Protocol for a Pilot, Feasibility Randomized Controlled Trial.2023https://dx.doi.org/10.3390/nu15214653
N.B. These documents automatically identified may not have been verified by the study sponsor.