Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621001321831
Ethics application status
Approved
Date submitted
31/08/2021
Date registered
28/09/2021
Date last updated
15/02/2022
Date data sharing statement initially provided
28/09/2021
Date results information initially provided
15/02/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
The effectiveness of SunGold (trademark) Kiwifruit consumption in supporting psychological wellbeing in an adult population.
Scientific title
The effectiveness of daily consumption of SunGold (Trademark) Kiwifruit on psychological wellbeing (mood, vitality, mental wellbeing) and gut health in an adult population experiencing mild to moderate psychological distress.
Secondary ID [1] 305175 0
None
Universal Trial Number (UTN)
U1111-1268-9752
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Psychological distress 323443 0
Gut function 323444 0
Sub-optimal vitamin C concentrations 323445 0
Condition category
Condition code
Mental Health 320996 320996 0 0
Other mental health disorders
Oral and Gastrointestinal 320997 320997 0 0
Normal oral and gastrointestinal development and function
Diet and Nutrition 321182 321182 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Brief name: Daily consumption of gold kiwifruit for 4 weeks
Arm 1: 2-week pre-intervention baseline.
Intervention:
Participants will be supplied with kiwifruit to store and consume in their own domicile for the duration of the study.
They will be instructed on storage and consumption protocols. Participants will be responsible for delivery of intervention.
Participants will complete a 2-week baseline prior to commencing the intervention phase. During the intervention phase participants will consume 2 gold kiwifruit each day for a period of 28 days.
The intervention will occur in the participant’s domicile.
Compliance will be monitored throughout the study. Participants will complete a daily paper log to assess protocol compliance. Compliance logs will be reviewed at each clinic visit. Any queries from the logs will be followed up via a phone call. Participants who consume less than 80% of the required product in a given fortnight will receive a courtesy call from site study staff to problem solve compliance issues. Subjects will be instructed to bring back any remaining product to site for accountability purposes. Compliance will also be assessed against blood biomarkers taken across the intervention.
Intervention code [1] 321572 0
Treatment: Other
Comparator / control treatment
Comparator Arm: 4-week pre-intervention baseline

Participants will be supplied with kiwifruit to store and consume in their own domicile for the duration of the study.
They will be instructed on storage and consumption protocols. Participants will be responsible for delivery of intervention.
Participants in the comparator arm will complete a 4-week baseline prior to commencing the intervention phase. During the intervention phase participants will consume 2 gold kiwifruit each day for a period of 28 days.
The intervention will occur in the participant’s domicile.
Compliance will be monitored throughout the study. Participants will complete a daily paper log to assess protocol compliance. Compliance logs will be reviewed at each clinic visit. Any queries from the logs will be followed up via a phone call. Participants who consume less than 80% of the required product in a given fortnight will receive a courtesy call from site study staff to problem solve compliance issues. Subjects will be instructed to bring back any remaining product to site for accountability purposes. Compliance will also be assessed against blood biomarkers taken across the intervention.
Control group
Active

Outcomes
Primary outcome [1] 328774 0
Mean difference in Profile of Mood States questionnaire short form (POMS-SF) total mood disturbance (TMD) scores between baseline and post-intervention.
Timepoint [1] 328774 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks (primary timepoint) after intervention commencement
Secondary outcome [1] 400288 0
Change in psychological wellbeing assessed as mean difference in scores on the Warwick-Edinburgh Mental Well-being Scale (WEBWMS) between post-intervention and baseline.
Timepoint [1] 400288 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks after intervention commencement
Secondary outcome [2] 400289 0
Changes in subjective vitality as assessed by the mean difference in scores on the Subjective Vitality Scale (SVS) between post-intervention and baseline.
Timepoint [2] 400289 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks after intervention commencement
Secondary outcome [3] 400290 0
Changes in psychological wellbeing as assessed by mean differences in scores on the Profile of Mood States – Short Form 6 sub-scales between post-intervention and baseline
Timepoint [3] 400290 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks after intervention commencement
Secondary outcome [4] 400291 0
Changes in psychological wellbeing as assessed by mean differences in scores on the Profile of Mood States-Brief between post-intervention and baseline
Timepoint [4] 400291 0
Baseline, weekly thereafter to 6-weeks post intervention commencement
Secondary outcome [5] 400292 0
Gut symptoms and intestinal comfort assessed by mean differences in scores on the Gastrointestinal Symptom Rating Scale (GSRS)
Timepoint [5] 400292 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks after intervention commencement
Secondary outcome [6] 400293 0
Mean difference in fasting plasma vitamin C concentrations (µmol/L) between post-intervention and baseline
Timepoint [6] 400293 0
Baseline, pre-intervention, 2 weeks, 4 weeks (post-intervention) and 6 weeks after intervention commencement

Eligibility
Key inclusion criteria
* 18-60 years of age inclusive
* male or female
* non-smoker (i.e. no history of smoking or nicotine replacement therapy within the last six months)
* plasma vitamin C >10µmol/L and < 50µmol/L (lower and upper thresholds for suboptimal vitamin C status)
* scores in the mild and moderate ranges on a minimum of one of either the depression (10-13 & 14-20), anxiety (8-9 & 10-14) and stress (15-18 & 19-25) subscales of the DASS-21 at screening
* willing to provide written informed consent
* access to smartphone and willing to download free application from app store
* able to access own email address/service
* fluent in English
Minimum age
18 Years
Maximum age
60 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
* aversion and/or allergy/intolerance to kiwifruit and/or latex
* needle phobia or fainting due to fear of needles
* scores in the severe or extremely severe ranges on a minimum of two of either the depression (greater than or equal to 21), anxiety (greater than or equal to 15) and stress (greater than or equal to 26) subscales of the DASS-21 at screening
* a score in the high range (greater than or equal to 7) on the Habitual Dietary Intake Questionnaire (HDIvC) at screening
* use of vitamin C or probiotics supplements within 84 days (3 months) of baseline and not prepared to abstain for the study duration
* previous or current diagnosis of Diabetes Mellitus or bleeding disorders (e.g., haemophilia)
* use of prescription medications for the treatment and management of gastrointestinal disorders within 84 days (3 months) of baseline and not prepared to abstain from use for the study duration
* initiation of, or alterations to, a course of anti-depressants, anxiolytic agents or anti-psychotics within last 6 months of baseline
* received an investigational drug within 84 days (3 months) prior to baseline that in the opinion of the Principal Investigator may affect the applicant’s ability to participate in the study of the study’s results

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)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Eligible participants will be assigned to either of the different baseline groups (2-week baseline or 4-week baseline) using a randomisation table created by computer software.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Other
Other design features
Study is a multiple-baseline design. Participants will be randomly allocated to one of either a 2-week or 4-week baseline period prior to commencing the intervention. Participants in both baseline groups will receive the same intervention.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Previous power calculations using Profile of Mood States -Short Form data indicated that at 80% power (alpha = 0.05), a minimum of 25 participants would be required to detect an effect size of 0.8. The trial will endeavour to recruit 30 participants in order to allow for attrition, intervention non-compliance or reporting errors from assessment measures.
Outcomes to be compared between the study groups include psychological wellbeing (mood, vitality), gut function and biochemical outcomes. The primary analyses will involve 2-way comparisons between the 2-week and 4-week baseline groups.
* a visual analysis of graphed data will be performed to examine data in adjacent phases examining for level, trend, and variability.
* intervention effect will be examined by determining changes in level, trend, variability, and degree of overlap across data points in baseline and data points in the intervention phase. (i.e., comparing data from Weeks 1 and 2 of the intervention in the 2-week baseline condition with Weeks 3 and 4 baseline data from the 4-week baseline condition. Comparison of data from the Phaseout period of the 2-week condition will then be compared against data from Weeks 3 and 4 of the 4-week condition.
* Statistical analysis will include aggregation of data for participants in the two- and four-week baselines to generate group mean treatment effects and trends in baseline data.

Recruitment
Recruitment status
Stopped early
Data analysis
Data collected is being analysed
Reason for early stopping/withdrawal
Participant recruitment difficulties
Date of first participant enrolment
Anticipated
1/11/2021
Actual
28/10/2021
Date of last participant enrolment
Anticipated
30/11/2021
Actual
11/11/2021
Date of last data collection
Anticipated
28/02/2022
Actual
6/01/2022
Sample size
Target
30
Accrual to date
Final
4
Recruitment in Australia
Recruitment state(s)
SA
Recruitment postcode(s) [1] 35200 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 309560 0
University
Name [1] 309560 0
University of Adelaide
Country [1] 309560 0
Australia
Primary sponsor type
Government body
Name
CSIRO
Address
Commonwealth Scientific and Industrial Research Organisation (CSIRO)
South Australian Health and Medical Research Institute (SAHMRI)
North Terrace
Adelaide SA 5000
Country
Australia
Secondary sponsor category [1] 310560 0
Commercial sector/Industry
Name [1] 310560 0
Zespri International Ltd
Address [1] 310560 0
Zespri International Ltd
400 Maunganui Road
Mt Maunganui 3116
New Zealand
Country [1] 310560 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 309340 0
CSIRO Health and Medical Human Research Ethics Committee
Ethics committee address [1] 309340 0
GPO Box 2583
Brisbane
Queensland 4001
Ethics committee country [1] 309340 0
Australia
Date submitted for ethics approval [1] 309340 0
23/04/2021
Approval date [1] 309340 0
25/08/2021
Ethics approval number [1] 309340 0
2021_047_HREC.

Summary
Brief summary
The aim of this study is to investigate the effects of daily consumption of gold kiwifruit on psychological health and wellbeing and other health related outcomes including biochemical parameters, and gut symptoms in adults aged 35-60 years with elevated (mild to moderate) stress, anxiety and depression. Gold kiwifruit contain exceptionally high levels of vitamin C. Vitamin C is recognised for its important role in mood, cognition and physical health and wellbeing. Gold kiwifruit has the potential to infer beneficial effects on the constructs of psychological wellbeing and gut health and functioning. The CSIRO will lead a 10-week trial involving daily delivery of gold kiwifruit in adults experiencing current mild to moderate levels of psychological distress and who present with sub-optimal vitamin C concentrations.
Trial website

Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 113826 0
Dr Ian Zajac
Address 113826 0
Nutrition and Health Program
Health and Biosecurity
CSIRO SAHMRI
North Terrace
Adelaide SA 5000
Country 113826 0
Australia
Phone 113826 0
+61 8 8303 8875
Fax 113826 0
Email 113826 0
[email protected]
Contact person for public queries
Name 113827 0
Dr Ian Zajac
Address 113827 0
Nutrition and Health Program
Health and Biosecurity
CSIRO SAHMRI
North Terrace
Adelaide SA 5000
Country 113827 0
Australia
Phone 113827 0
+61 8 8303 8875
Fax 113827 0
Email 113827 0
[email protected]
Contact person for scientific queries
Name 113828 0
Dr Ian Zajac
Address 113828 0
Nutrition and Health Program
Health and Biosecurity
CSIRO SAHMRI
North Terrace
Adelaide SA 5000
Country 113828 0
Australia
Phone 113828 0
+61 8 8303 8875
Fax 113828 0
Email 113828 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
No IPD sharing has been approved under the ethics approval for this study.


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
No additional documents have been identified.