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Trial registered on ANZCTR


Registration number
ACTRN12620001362987
Ethics application status
Approved
Date submitted
14/10/2020
Date registered
17/12/2020
Date last updated
26/11/2023
Date data sharing statement initially provided
17/12/2020
Date results provided
26/11/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
TANDIM: Treating Anxiety and Depression in Irritable Bowel Syndrome (IBS) using diet: A proof-of-concept study
Scientific title
Reducing symptom burden in individuals with irritable bowel syndrome (IBS) and comorbid anxiety or depression: Is a Mediterranean diet intervention feasible?
Secondary ID [1] 302519 0
None
Universal Trial Number (UTN)
Trial acronym
TANDIM
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Irritable Bowel Syndrome 319387 0
Anxiety 319388 0
Depression 319389 0
Condition category
Condition code
Oral and Gastrointestinal 317354 317354 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon
Mental Health 317673 317673 0 0
Anxiety
Mental Health 317674 317674 0 0
Depression

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study aims to recruit 60 individuals with IBS and current anxiety or depressive symptoms aged between 18 and 65 years. This study will be conducted via online Zoom videoconferencing and telephone. There will be no in-person appointments. All screening, study visits and dietary advice will be implemented by the study dietitians (gastrointestinal specialists; 2 and 18 years' experience).

After screening and consent, participants will complete a short online questionnaire about gastrointestinal symptoms daily for seven days and an online food diary daily for 3 days, both prior to allocation to the intervention or control group. Before the first study visit, a stool sample collection kit will be provided for participants to collect a stool sample in their home.

First study visit:
The first study visit (baseline) will be conducted on Zoom for approximately 60 minutes. During this visit, demographic details and medical history will be collected, and participants will complete online questionnaires about psychological symptoms, gastrointestinal symptoms, and diet. Participants will then be randomly allocated to one of two groups for six weeks:

1. Intervention group – participants receive Mediterranean dietary advice, or;
2. Control group – participants continue regular diet

Those randomised to the intervention group will receive Mediterranean dietary advice, including information about food group targets, practical shopping advice, and written resources such as recipes. These resources have been designed specifically for this study. A food hamper will be provided via supermarket delivery in the first week of the intervention to facilitate adherence. The diet will be personalised, depending on food preferences and gastrointestinal (GI) symptoms.

Weekly contact:
Participants in the intervention and control group will be contacted weekly (by Zoom videoconferencing or telephone) to ask about their current health, medications and adverse events. This is also an opportunity for those in the intervention group to ask questions about the diet. For individuals in the intervention group, weekly goal setting activities will facilitate dietary adherence. The duration of these phone calls will be approximately 10 minutes.

Final study visit:
The final visit will take place in week 6 on Zoom for approximately 60 minutes. Participants will repeat the questionnaires completed at the first study visit. If participants are in the intervention group, they will also complete one additional questionnaire about their diet. In preparation for the final study visit, participants will complete a short online questionnaire about gastrointestinal symptoms daily for seven days. An online food diary will also be completed daily for 3 days. A second stool sample collection kit will be provided for participants to collect a stool sample in their home. Dietary adherence (for both intervention and control group) will be assessed via the 3-day online food diary and the dietary questionnaire completed at the final study visit.
Intervention code [1] 318812 0
Lifestyle
Comparator / control treatment
Those individuals randomised to the control group will be instructed to continue their habitual (usual) diet. All research activities that occur for the intervention group will also occur for the controls (questionnaires, biological samples, weekly phone calls), except for the dietary advice. At the end of the study, participants in the control group will be offered Mediterranean dietary advice and a food hamper.

Control group
Active

Outcomes
Primary outcome [1] 325396 0
Feasibility will be evaluated by measuring the following:
- Diet intervention feasibility using a validated Mediterranean diet questionnaire (MEDAS)
- Study feasibility including number of screened and eligible patients, rate of recruitment and attrition, using a study-specific database.
Timepoint [1] 325396 0
At the end of the intervention (Week 6)
Primary outcome [2] 325719 0
Acceptability will be evaluated by measuring the following:
- Validated diet satisfaction score (DSS)
Timepoint [2] 325719 0
At the end of the intervention (Week 6)
Secondary outcome [1] 387770 0
Change in GI symptoms compared with controls
Outcome will be assessed via Gastrointestinal Symptom Rating Scale (GSRS), IBS-SSS Irritable Bowel Syndrome Severity Scoring System (IBS-SSS), Bristol Stool Form Scale (BSFS)
Timepoint [1] 387770 0
At the end of the intervention (Week 6)
Secondary outcome [2] 388900 0
Change in psychological symptoms compared with controls
Outcome will be assessed via Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS) and Somatisation Questionnaire (PHQ-12).
Timepoint [2] 388900 0
At the end of the intervention (Week 6)
Secondary outcome [3] 388901 0
Change in quality of life compared with controls
Outcome will be assessed via IBS quality of life questionnaire (IBS-QOL)
Timepoint [3] 388901 0
At the end of the intervention (Week 6)
Secondary outcome [4] 388902 0
Impact on the microbiome compared with controls
Outcome will be assessed via metagenomic sequencing
Timepoint [4] 388902 0
At the end of the intervention (Week 6)
Secondary outcome [5] 388904 0
Safety: nutritional adequacy and weight change compared with controls
Outcome will be assessed via food diary and compared to nutrient reference values, and participant self-reported weight
Timepoint [5] 388904 0
At the end of the intervention (Week 6)

Eligibility
Key inclusion criteria
Inclusion criteria
• Aged 18-65 years
• IBS diagnosis (Rome IV criteria) of any IBS subtype (diarrhea-predominant, constipation-predominant, mixed, un-subtyped)
• Hospital anxiety and depression score (HADS) subscale score of 8-14, indicating mild or moderately severe anxiety or depressive symptoms
•Access to computer and internet access
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• Known or suspected major medical conditions
• Females who report to be pregnant or lactating
• Unable to follow Mediterranean diet study recommendations (e.g. veganism, lacto-ovo vegetarians, inability to follow for sociocultural or religious reasons)
• Co-existing eating disorder or highly disordered eating
• Underweight (BMI <18.5 kg/m2) or obesity (>40 kg/m2)
• Change in IBS or anxiety/depression medication or exposure to pre- or probiotic supplements in the last month or antibiotics or bowel preparation for investigative procedures within the past three months

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
The randomisation sequence will be computer generated via a member of the team not involved in data collection. The treatment allocation will be conducted by the researcher conducting the baseline visits using REDCap after all baseline assessments are complete. The randomisation schedule and coding of group allocations will not be accessible to the researchers collecting the data at any time.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random block sizes will be used
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
The primary outcomes are feasibility and acceptability. The intervention will be considered feasible if there is a change in mean diet questionnaire score of greater than or equal to 2 in the intervention group, indicating success in individuals in altering diet towards the specific diet. Study feasibility will be informed by a number of factors including number of screened patients, number of eligible patients, rate of recruitment, retention rate. With regards to attrition, a higher drop-out may be indicative of difficulty in adhering to the diet. The acceptability of the intervention will be based on diet satisfaction score.

Feasibility and acceptability will be assessed using descriptive analysis. Diet, clinical symptoms and anthropometry will be compared between groups using appropriate parametric or non-parametric analyses and will be considered significant where p<0.05. Correction using Bonferroni adjustment or FDR correction will occur where required. Microbiome data will be analysed individually and as combined datasets with the support of a data scientist.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
ACT,NSW,NT,QLD,SA,TAS,WA,VIC
Recruitment hospital [1] 17811 0
Epworth Hospital Geelong - Waurn Ponds
Recruitment hospital [2] 17812 0
St John of God Hospital, Geelong - Geelong
Recruitment postcode(s) [1] 31668 0
3216 - Waurn Ponds
Recruitment postcode(s) [2] 31669 0
3220 - Geelong

Funding & Sponsors
Funding source category [1] 306956 0
University
Name [1] 306956 0
Deakin University
Country [1] 306956 0
Australia
Funding source category [2] 306960 0
Charities/Societies/Foundations
Name [2] 306960 0
Waterloo Foundation
Country [2] 306960 0
United Kingdom
Primary sponsor type
University
Name
Deakin University
Address
Health Education Research Building (HERB)
Level 3, Rear of Kitchener House
285 Ryrie Street, P.O. Box 281
Geelong VIC 3220 Australia
Country
Australia
Secondary sponsor category [1] 307520 0
None
Name [1] 307520 0
Address [1] 307520 0
Country [1] 307520 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 307093 0
Barwon Health HREC
Ethics committee address [1] 307093 0
Ethics committee country [1] 307093 0
Australia
Date submitted for ethics approval [1] 307093 0
24/06/2020
Approval date [1] 307093 0
05/10/2020
Ethics approval number [1] 307093 0
HREC/65566/VICBH-2020-234213(v4)

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 106006 0
Dr Heidi Staudacher
Address 106006 0
Food & Mood Research Centre, IMPACT Institute, School of Medicine
Health Education Research Building (HERB), Level 3, Rear of Kitchener House, 285 Ryrie Street, P.O. Box 281
Geelong VIC 3220
Country 106006 0
Australia
Phone 106006 0
+61 3 5227 8891
Fax 106006 0
Email 106006 0
Contact person for public queries
Name 106007 0
Sophie Mahoney
Address 106007 0
Food & Mood Research Centre, IMPACT Institute, School of Medicine
Health Education Research Building (HERB), Level 3, Rear of Kitchener House, 285 Ryrie Street, P.O. Box 281
Geelong VIC 3220
Country 106007 0
Australia
Phone 106007 0
+61 3 5227 8622
Fax 106007 0
Email 106007 0
Contact person for scientific queries
Name 106008 0
Heidi Staudacher
Address 106008 0
Food & Mood Research Centre, IMPACT Institute, School of Medicine
Health Education Research Building (HERB), Level 3, Rear of Kitchener House, 285 Ryrie Street, P.O. Box 281
Geelong VIC 3220
Country 106008 0
Australia
Phone 106008 0
+61 3 5227 8891
Fax 106008 0
Email 106008 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Participant data supporting the publication results.
When will data be available (start and end dates)?
Data are available straight after publication.
Data are available for an indefinite time.
Start date: Pending publication.
End date: Unknown.
Available to whom?
Data are potentially available to:
- Researchers
Based in:
- Any location
Further information:
All data requests will be considered by the primary sponsor on a case-by-case basis. Requests must include a methodologically sound proposal. Specific conditions of use may apply and will be specified in a data sharing agreement (or similar) that the requester must agree to before access is granted. For further information, see our data sharing policy (https://policy.deakin.edu.au/view.current.php?id=00023)
Available for what types of analyses?
Assessed on a case-by-case basis.
How or where can data be obtained?
Access can be requested via the Health Data Australia catalogue (https://www.researchdata.edu.au/health). Search for the ACTRN number in the catalogue to find datasets associated with this trial. For further information, see our data sharing policy: https://policy.deakin.edu.au/view.current.php?id=00023


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
19905Data dictionary    380737-(Uploaded-17-07-2023-11-20-33)-Study-related document.csv



Results publications and other study-related documents

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

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseClinical trial: A Mediterranean diet is feasible and improves gastrointestinal and psychological symptoms in irritable bowel syndrome.2024https://dx.doi.org/10.1111/apt.17791
N.B. These documents automatically identified may not have been verified by the study sponsor.