Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619001294145
Ethics application status
Approved
Date submitted
22/08/2019
Date registered
19/09/2019
Date last updated
1/10/2023
Date data sharing statement initially provided
19/09/2019
Date results information initially provided
1/10/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
VEgetableS for vaScular hEaLth: The VESSEL Study
Scientific title
A randomised controlled crossover trial investigating the short-term effects of different types of vegetables on vascular and metabolic function in middle-aged and older adults with mildly elevated blood pressure
Secondary ID [1] 298779 0
None
Universal Trial Number (UTN)
Trial acronym
VESSEL (VEgetableS for vaScular hEaLth)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Blood pressure 313907 0
Glycemic control 313908 0
Inflammation 313909 0
Oxidative stress 313910 0
Arterial stiffness 316234 0
Condition category
Condition code
Cardiovascular 312320 312320 0 0
Normal development and function of the cardiovascular system
Metabolic and Endocrine 312321 312321 0 0
Normal metabolism and endocrine development and function
Inflammatory and Immune System 312322 312322 0 0
Normal development and function of the immune system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The two 2-week dietary treatments will correspond to:
1. Cruciferous vegetables (CV): 4 servings (~300 g) of cruciferous vegetables (broccoli, cabbage, cauliflower, and kale) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day); and
2. Starchy vegetables (SV): 4 servings (~300 g) of commonly consumed vegetables (potato, sweet potato, carrot, and pumpkin) per day consumed as a soup at lunch and dinner (~500-600 mL soup/day).
Both treatment soups will be approximately matched for energy, protein, fat, and carbohydrate content. Soups will be prepared at Edith Cowan University, Joondalup Campus, using a standardized recipe and frozen for storage.
Participants will be advised to consume their regular breakfast and snacks during the trial and to keep this consistent throughout. During intervention periods, participants will consume standard lunch and dinner meals provided by the study investigators to limit background dietary variation. The lunch and dinner meals provided to participants will be pre-packaged frozen meals available from supermarkets (e.g. McCain Healthy Choices, Lean Cuisine). It is expected that participants will have a background vegetable intake of approximately 1-4 servings per day during the intervention periods. Therefore, the additional 4 servings of vegetables that the soups will provide will shift vegetable intake to at or above the recommended 5-6 servings per day.
There will be a 2-week washout period between the two intervention periods. A daily food diary will be used, along with other compliance measures, to monitor adherence throughout the study. Daily food diaries will either be paper-based or app-based (Food Research Diary, Xyris Software, Australia), depending on participant preference. All food data will later be entered into Foodworks (Xyris Software, Australia) for analysis.
Intervention code [1] 315206 0
Prevention
Comparator / control treatment
Participants will act as their own control (crossover study). The SV soup is considered the comparator/control treatment.
Control group
Active

Outcomes
Primary outcome [1] 320954 0
24 hour ambulatory blood pressure assessed using an Oscar 2TM ambulatory blood pressure monitor (SunTech Medical Inc., Morrisville, NC, USA).
Timepoint [1] 320954 0
Ambulatory blood pressure will be assessed at the beginning and end of each intervention period.
Secondary outcome [1] 373490 0
Glycaemic control will be assessed using a Flash Glucose Monitoring System (Freestyle Libre; Abbott Diabetes Care Inc., Alameda, CA, USA).
Timepoint [1] 373490 0
Glycaemic control will be assessed using continuous glucose monitoring commencing from the start of each intervention period to the end of each intervention period.
Secondary outcome [2] 373491 0
Inflammation will be assessed as a composite secondary outcome by measuring serum high sensitivity interleukin-6 (hsIL-6) and high sensitivity C-reactive protein (hsCRP) from a serum sample. hsIL-6 will be analysed using commercially available ELISA kits and hsCRP will be analysed using routine laboratory techniques at Fiona Stanley Hospital, Perth, WA.
Timepoint [2] 373491 0
Inflammatory markers will be assessed at the beginning and end of each intervention period.
Secondary outcome [3] 373492 0
Oxidative stress will be assessed by measuring plasma F2-isoprostanes. Plasma F2-Isoprostanes will be measured as total (free plus esterified) F2-isoprostanes using electron-capture negative-ion gas chromatography-mass spectrometry.
Timepoint [3] 373492 0
Oxidative stress markers will be assessed at the beginning and end of each intervention period.
Secondary outcome [4] 379973 0
Ambulatory arterial stiffness assessed using an Oscar 2TM ambulatory blood pressure monitor (SunTech Medical Inc., Morrisville, NC, USA).
Timepoint [4] 379973 0
Ambulatory arterial stiffness will be assessed at the beginning and end of each intervention period.

Eligibility
Key inclusion criteria
We will recruit ambulant community-dwelling men and women aged between 50 and 75 years who have mildly elevated blood pressure (systolic blood pressure 120-160 mmHg, inclusive, and diastolic blood pressure <100 mmHg).
Minimum age
50 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Volunteers will be excluded from participation based on the following criteria: body mass index <18.5 or =40 kg/m2; systolic blood pressure >160 mmHg or <120 mm Hg; diastolic blood pressure >100 mmHg; use of >2 antihypertensive medications or irregular use of nitric oxide donors, organic nitrites and nitrates, and sildenafil and related drugs; diagnosed diabetes or fasting blood glucose >6.5 mmol/L; fasting total cholesterol >8 mmol/L; current or recent (<12 months) smoking; adhesive allergy; regular aspirin use; medication use for thrombosis or anticoagulants (Warfarin); history of cardiovascular or peripheral vascular disease (myocardial infarction, stroke, transient ischaemic attack, amputation due to arterial insufficiency, any form of arterial revascularisation, history of exertional angina or claudication); psychiatric illness or other major illnesses, such as cancer; alcohol intake >100 g per week; current or recent (within previous 6 months) significant weight loss or gain (>6% of body weight) or actively trying to lose weight; pre-menopausal women; inability to attend clinic/office visits; use of antibiotics (within previous 2 months); use of antibacterial mouthwash and not willing to cease for trial duration; reported participation in night shift work during the study period; and inability or unwillingness to follow the study protocol. Volunteers with specific dietary requirements, allergies, or intolerances (e.g. following a low FODMAP diet) that will interfere with their ability to follow the dietary requirements of the study will also be excluded.

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)
Eligible participants will be randomly assigned to one of 2 sequence orders using computer generated random numbers. 50 sealed opaque envelopes, numbered 1-50, each containing one of the 2 sequence orders for intervention diets will be used for randomisation by opening an envelope, in consecutive order, as participants are entered into the study. The computer generated random numbers and sealed opaque envelopes will be completed and held by a person independent of study researchers within Edith Cowan University. The study coordinator will contact the person independent of study researchers to obtain the next available envelope once an individual is deemed eligible. The envelope will be opened and the code will be recorded.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer-generated random numbers using Microsoft Excel.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Statistical analyses will be performed using IBM SPSS Statistics for Windows, version 25.0 (IBM Corp., Armonk, NY, USA) and STATA, version 16.0 (Statacorp, College Station, TX, USA). Statistical significance will be set at a 2-sided Type 1 error rate of P<0.05. Descriptive statistics of normally distributed continuous variables will be expressed as mean ± standard deviation (SD), non-normally distributed continuous variables as median and interquartile range, and categorical variables as number and proportion (%). The primary analyses will be performed according to a modified intention to treat protocol and will include all randomised participants for which baseline data is obtained. Multilevel models will be used to assess the effect of the dietary interventions and these will produce unbiased estimates of the treatment effects whenever there are small amounts of missing data (i.e. <10%). Where there is >10% missing data, multiple imputation will be used as a sensitivity analysis.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
17/02/2020
Actual
5/02/2020
Date of last participant enrolment
Anticipated
30/06/2020
Actual
17/09/2021
Date of last data collection
Anticipated
31/08/2020
Actual
26/11/2021
Sample size
Target
28
Accrual to date
Final
21
Recruitment in Australia
Recruitment state(s)
WA
Recruitment hospital [1] 14433 0
Royal Perth Hospital - Perth
Recruitment postcode(s) [1] 27443 0
6000 - Perth

Funding & Sponsors
Funding source category [1] 303336 0
University
Name [1] 303336 0
Edith Cowan University
Country [1] 303336 0
Australia
Primary sponsor type
University
Name
Edith Cowan University
Address
270 Joondalup Drive
Joondalup WA 6027
Country
Australia
Secondary sponsor category [1] 303527 0
None
Name [1] 303527 0
Address [1] 303527 0
Country [1] 303527 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303865 0
Edith Cowan University Human Research Ethics Committee
Ethics committee address [1] 303865 0
270 Joondalup Drive
Joondalup WA 6027
Ethics committee country [1] 303865 0
Australia
Date submitted for ethics approval [1] 303865 0
14/01/2020
Approval date [1] 303865 0
15/01/2020
Ethics approval number [1] 303865 0
2019-00356-BLEKKENHORST

Summary
Brief summary
The aim of this study is to determine whether regular consumption of cruciferous vegetables (e.g. broccoli, cabbage, cauliflower, kale) results in short-term improvement in measures related to cardiovascular disease risk, including blood pressure, arterial stiffness, glycaemic control, and circulating biomarkers of oxidative stress and inflammation. Twenty-eight participants (50-75 years) with mildly elevated blood pressure (systolic blood pressure 120-160 mmHg) will complete two 2-week interventions in a random order, separated by a 2-week washout period. During each intervention, participants will consume 4 servings/day (300 g) of vegetables as a soup (~500-600 mL/day). The 'active' soup will consist of cruciferous vegetables (broccoli, cabbage, cauliflower, kale) and the ‘control’ soup will consist of other commonly consumed vegetables (potato, sweet potato, carrot, pumpkin). Both soups will be approximately matched for energy, protein, fat, and carbohydrate content. All measurements will be performed at the beginning and end of each intervention period.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 95070 0
Dr Lauren Blekkenhorst
Address 95070 0
Edith Cowan University
270 Joondalup Drive
Joondalup WA 6027
Country 95070 0
Australia
Phone 95070 0
+61 8 63044604
Fax 95070 0
Email 95070 0
[email protected]
Contact person for public queries
Name 95071 0
Dr Lauren Blekkenhorst
Address 95071 0
Edith Cowan University
270 Joondalup Drive
Joondalup WA 6027
Country 95071 0
Australia
Phone 95071 0
+61 8 63044604
Fax 95071 0
Email 95071 0
[email protected]
Contact person for scientific queries
Name 95072 0
Dr Lauren Blekkenhorst
Address 95072 0
Edith Cowan University
270 Joondalup Drive
Joondalup WA 6027
Country 95072 0
Australia
Phone 95072 0
+61 8 63044604
Fax 95072 0
Email 95072 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
We do not have ethics approval to share individual participant data.


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
EmbaseA randomised controlled crossover trial investigating the short-term effects of different types of vegetables on vascular and metabolic function in middle-aged and older adults with mildly elevated blood pressure: The VEgetableS for vaScular hEaLth (VESSEL) study protocol.2020https://dx.doi.org/10.1186/s12937-020-00559-3
N.B. These documents automatically identified may not have been verified by the study sponsor.