Trial Review

Technical difficulties have been reported by some users of the search function and is being investigated by technical staff. Thank you for your patience and apologies for any inconvenience caused.

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
ACTRN12621000769886
Ethics application status
Approved
Date submitted
11/05/2021
Date registered
21/06/2021
Date last updated
15/05/2024
Date data sharing statement initially provided
21/06/2021
Date results information initially provided
15/05/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of kiwifruit on vitamin C status of people susceptible to respiratory infections
Scientific title
Effect of kiwifruit intervention on vitamin C status of people with recurrent respiratory infections
Secondary ID [1] 303626 0
None
Universal Trial Number (UTN)
U1111-1265-5557
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
recurrent respiratory infection 321008 0
low vitamin C status 322221 0
Condition category
Condition code
Respiratory 318813 318813 0 0
Other respiratory disorders / diseases
Diet and Nutrition 319916 319916 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This is a 'before and after' study whereby participants will consume kiwifruit following baseline visit.

- the dose administered: 2 SunGold kiwifruit per day
- the frequency of administration: once per day
- the duration of administration: 6 weeks
- the mode of administration: oral

Adherence to intervention will be monitored through measuring plasma vitamin C concentrations (by HPLC)
Intervention code [1] 319927 0
Treatment: Other
Comparator / control treatment
The baseline clinic visit is the comparator for the subsequent intervention phase.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 326774 0
Plasma vitamin C concentrations - measured using high performance liquid chromatography (HPLC)
Timepoint [1] 326774 0
Baseline, 2 weeks and 6 weeks (primary timepoint) after admission
Secondary outcome [1] 392637 0
Complete blood cell count and differential (coulter counter)
Timepoint [1] 392637 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [2] 392638 0
Immunometabolic state of lymphocytes derived from blood samples (measured using flow cytometry)
Timepoint [2] 392638 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [3] 392639 0
Inflammatory markers in blood samples: eg C-reactive protein (Immunoturbidimetric, latex immunoassay), procalcitonin (enzyme-linked immunosorbent assay - ELISA), myeloperoxidase (ELISA)
Timepoint [3] 392639 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [4] 392640 0
Oxidative stress biomarkers, e.g. urinary F2isoprostanes (ELISA)
Timepoint [4] 392640 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [5] 392641 0
Respiratory symptoms: eg cough, breathlessness, sputum characteristics (from Quality of Life Questionnaire - bronchiectasis - QOL-B)
Timepoint [5] 392641 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [6] 392642 0
Quality of life (from Quality of Life Questionnaire - bronchiectasis - QOL-B)
Timepoint [6] 392642 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [7] 392643 0
Fatigue (Multidimensional Fatigue Symptom Inventory)
Timepoint [7] 392643 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [8] 396600 0
Subjective mood - eg anxiety and depression (Hospital Anxiety and Depression Scale)
Timepoint [8] 396600 0
Baseline, 2 weeks and 6 weeks after admission
Secondary outcome [9] 396601 0
Upper respiratory tract infection susceptibility and severity (Wisconsin Upper Respiratory Symptom Survey)
Timepoint [9] 396601 0
Daily for duration of symptoms (during control and intervention phases - 6 weeks each)

Eligibility
Key inclusion criteria
Inclusion criteria:
adult aged 18 years and over;
respiratory symptoms indicating IV antibiotic therapy in the previous year;
symptoms occurring at least once per year
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion criteria:
not able to give consent,
severe coexisting medical conditions (other than bronchiectasis) which would worsen the prognosis (e.g. heart failure, lung cancer, COPD, cystic fibrosis),
dysphagia (swallowing difficulties),
known kiwifruit allergy,
taking vitamin C-containing supplements at greater than recommended dietary intake (RDI).

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
NA
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
NA
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Before and after trial
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Statistical analyses will be carried out by an experienced biostatistician. Patient characteristics at baseline will be summarised by treatment group using simple descriptive statistics. The proportion of patients achieving adequate vitamin C status shall be calculated with binomial 95% confidence intervals (CI) for each group. Absolute and relative group differences, and numbers needed to treat, shall be calculated with 95% CI, and statistical significance tested using Fisher’s exact test. Data will be stratified by baseline disease severity.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
21/06/2021
Actual
19/11/2021
Date of last participant enrolment
Anticipated
Actual
15/06/2023
Date of last data collection
Anticipated
Actual
10/10/2023
Sample size
Target
20
Accrual to date
Final
20
Recruitment outside Australia
Country [1] 23521 0
New Zealand
State/province [1] 23521 0
Canterbury

Funding & Sponsors
Funding source category [1] 308047 0
Commercial sector/Industry
Name [1] 308047 0
Zespri International Ltd
Country [1] 308047 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
362 Leith Street
North Dunedin
Dunedin 9016
Country
New Zealand
Secondary sponsor category [1] 308789 0
None
Name [1] 308789 0
Address [1] 308789 0
Country [1] 308789 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 308039 0
Northern B Health and Disability Ethics Committee
Ethics committee address [1] 308039 0
Ministry of Health
Health and Disability Ethics Committees
133 Molesworth Street
Thorndon
Wellington 6011
Ethics committee country [1] 308039 0
New Zealand
Date submitted for ethics approval [1] 308039 0
11/05/2021
Approval date [1] 308039 0
31/05/2021
Ethics approval number [1] 308039 0
21/NTB/138

Summary
Brief summary
People with respiratory infections can exhibit depleted vitamin C status due to the increased turnover and requirement for the vitamin during the inflammatory process. We plan to carry out a 'before and after' study in people susceptible to infectious respiratory exacerbations requiring home antibiotic administration to assess their vitamin C status before and after supplementation with vitamin C-rich kiwifruit (assessed at baseline, 2 weeks and 6 weeks).

Secondary outcomes will include assessment of blood and urinary markers of inflammation, oxidative stress and white blood cell status. Questionnaires will assess respiratory symptoms, health-related quality of life, subjective mood, and susceptibility to and severity of subsequent upper respiratory tract infections.

We hypothesise that supplementation of vitamin C-rich kiwifruit to these people will enhance their vitamin C status and may decrease inflammatory and oxidative stress biomarkers and improve immune cell parameters. Although not powered to detect changes in clinical outcomes, this data will be used to inform future trials.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 109306 0
A/Prof Anitra Carr
Address 109306 0
University of Otago, Christchurch
2 Riccarton Avenue
Christchurch Central City
Christchurch 8011
Country 109306 0
New Zealand
Phone 109306 0
+6433640649
Fax 109306 0
Email 109306 0
anitra.carr@otago.ac.nz
Contact person for public queries
Name 109307 0
A/Prof Anitra Carr
Address 109307 0
University of Otago, Christchurch
2 Riccarton Avenue
Christchurch Central City
Christchurch 8011
Country 109307 0
New Zealand
Phone 109307 0
+6433640649
Fax 109307 0
Email 109307 0
anitra.carr@otago.ac.nz
Contact person for scientific queries
Name 109308 0
A/Prof Anitra Carr
Address 109308 0
University of Otago, Christchurch
2 Riccarton Avenue
Christchurch Central City
Christchurch 8011
Country 109308 0
New Zealand
Phone 109308 0
+6433640649
Fax 109308 0
Email 109308 0
anitra.carr@otago.ac.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Individual participant data will not be made available to researchers who are not directly collaborating with the study researchers as the ethics application does not allow for this.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Study results articleYes SunGold Kiwifruit Consumption Restores Adequate to... [More Details]

Documents added automatically
No additional documents have been identified.