Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621000642886
Ethics application status
Approved
Date submitted
19/04/2021
Date registered
28/05/2021
Date last updated
13/07/2023
Date data sharing statement initially provided
28/05/2021
Date results information initially provided
13/07/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
Investigating the impact of Online Grocery Shopping on Blood Pressure in Individuals with Hypertension
Scientific title
The Online Grocery Shopping (OGS) Trial: Investigating the impact of a Novel Method on Blood Pressure Among Individuals with Hypertension.
Secondary ID [1] 303490 0
National Health and Medical Research Council APP1200105
Universal Trial Number (UTN)
U1111-1264-6104
Trial acronym
OGS
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypertension 320808 0
Condition category
Condition code
Cardiovascular 318629 318629 0 0
Hypertension

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Each participant in the intervention arm of the study will receive an Online Grocery Shopping (OGS) web-browser application, such that every time they purchase groceries online, OGS application will provide immediate on-screen, interpretive (i.e. colour-coded symbol) nutrition information and specific suggestions for lower salt alternatives. Participants will be asked to self measure their blood pressure at 3 time points (baseline, week 6 and week 12) during the study using a wireless home blood pressure monitor which will be provided to them. Participants will also be required to attend a local pathology centre to provide a spot urine sample for electrolyte measurement at two time points (baseline and week 12). Participants will be required to use the Online Grocery Shopping (OGS) web-browser application to carry out all of their grocery shopping for a period of 12 weeks.
Participants will be given detailed instructions on how to download the web-browser extension (the intervention tool). Once downloaded, it works by way of a pop up screen offering healthy alternatives to certain products which the participant can select to purchase if they so wish. No training is necessary as it is self-explanatory; however, the intervention group will be supplied with a FAQs sheet on what to expect and how to interpret the information provided on the pop up screen if needed.
We will be conducting a mixed method process evaluation of the intervention which includes assessing implementation fidelity. We will triangulate routinely-collected data captured by the web browser (e.g. food purchases and frequency of use of the intervention tool) and semi-structured interviews with a subset of intervention participants to understand acceptability of the intervention, implementation fidelity and the barriers and facilitators of implementation.
Intervention code [1] 319779 0
Treatment: Other
Comparator / control treatment
No Treatment
Control group will still be required to purchase their groceries online via Woolworths.
Control group
Active

Outcomes
Primary outcome [1] 326592 0
Difference in mean sodium density (mg sodium per kcal energy) of grocery purchases between the intervention and control groups over 12 weeks.
Timepoint [1] 326592 0
baseline to 12 weeks
Secondary outcome [1] 392019 0
Change in mean diastolic blood pressure from baseline to 12 weeks. Measured with a wireless blood pressure monitor validated for home blood pressure monitoring supplied to all participants.
Timepoint [1] 392019 0
from baseline to 12 weeks
Secondary outcome [2] 392020 0
Change in mean urinary salt (sodium) excretion
Timepoint [2] 392020 0
from baseline to 12 weeks
Secondary outcome [3] 392021 0
Change in mean salt content of purchased food overall and by categories.
The web browser tool will collect participant data on what foods were purchased.
Timepoint [3] 392021 0
from baseline to 12 weeks.
Secondary outcome [4] 392022 0
Change in self-reported mean dietary salt intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [4] 392022 0
from baseline to 12 weeks.
Secondary outcome [5] 395652 0
Change in self-reported mean dietary fruit intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [5] 395652 0
from baseline to 12 weeks.
Secondary outcome [6] 395653 0
Change in self-reported mean dietary vegetable intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [6] 395653 0
from baseline to 12 weeks.
Secondary outcome [7] 395666 0
Change in self-reported mean dietary processed meats intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [7] 395666 0
from baseline to 12 weeks
Secondary outcome [8] 395667 0
Change in self-reported mean dietary salty snacks intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [8] 395667 0
baseline to 12 weeks
Secondary outcome [9] 395668 0
Change in self-reported mean dietary sauce intake.
We will be using the Automated Self-Administered 24-hour (ASA 24) Dietary Assessment Tool to collect information about dietary intake (https://asa24.nci.nih.gov/)
Timepoint [9] 395668 0
baseline to 12 weeks

Eligibility
Key inclusion criteria
We will include people who:
• Are adults between 18 and 75 years of age.
• Have a diagnosis by their clinician of high blood pressure or are currently taking a stable dose of blood pressure lowering medication, defined as no change to the dose in the past 6 months.
• Regularly shop and purchase most of their groceries online via Woolworths and plan to continue for the approx. 4 months duration of the study, OR Regularly shop and purchase most of their groceries online via a non-Woolworths retailer (e.g. Coles); but are willing to switch to shop at Woolworths online for the duration of the study.
• Use, or will use, a computer (laptop or desktop) to shop for their groceries online (i.e. not a mobile phone or tablet/iPad)
• Are assessed as demonstrating high salt purchasing behaviour
• Do not have another household member already participating in this trial
• Are the main person who shops for food and groceries in their household
• Have an upper arm circumference of less than 42cm (i.e. do not require an extra-large blood pressure cuff when measuring blood pressure)
• Successfully completes the run-in procedures, which will occur at the beginning of the study
Minimum age
18 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
We will exclude those who:
• Are less than 18 years of age or 75 years of age or older
• Are unable or unwilling to provide informed consent.
• Have an upper arm circumference of more than 48cm (measured mid-way between your shoulder and elbow).
• Have one or more of the following advanced medical conditions:
o Congestive heart failure (stage D)
o Stage 4/advanced/metastatic cancer
o Chronic kidney disease (CKD), Chronic Kidney failure (stage 4) and end-stage renal disease on dialysis (Stage 5)
o Advanced liver disease, Cirrhosis, end-stage liver disease (ESLD)
o Those with a life expectancy less than 1 year

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)
Central randomisation by phone/fax/computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation).
Stratified allocation: randomisation will be performed by an online computerised system in a 1:1 ratio and stratified by age (=50 years/>50 years), sex, and baseline BP medication use (Yes/No).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
We plan to randomize a total of 1,966 participants. Assuming up to 10% dropout by the 12-weeks follow-up time point, we anticipate an analytic sample size of 1,768 participants (1:1 allocation). For primary outcome analyses, our target sample size will provide 80% power to detect a 2 mmHg or greater difference in SBP between the intervention and comparator arms assuming a two-sided 5% level of significance and a 15 mmHg standard deviation in SBP.

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
30/09/2021
Actual
2/07/2021
Date of last participant enrolment
Anticipated
30/06/2023
Actual
30/06/2023
Date of last data collection
Anticipated
29/09/2023
Actual
Sample size
Target
127
Accrual to date
Final
183
Recruitment in Australia
Recruitment state(s)
ACT,NSW,NT,QLD,SA,TAS,WA,VIC

Funding & Sponsors
Funding source category [1] 307907 0
Government body
Name [1] 307907 0
NHMRC
Country [1] 307907 0
Australia
Primary sponsor type
Other Collaborative groups
Name
The George Institute for Global Heath
Address
Level 5, 1 King St
Newtown
NSW 2042
Country
Australia
Secondary sponsor category [1] 308620 0
None
Name [1] 308620 0
Address [1] 308620 0
Country [1] 308620 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 307906 0
University of New South Wales Human Research Ethics Committee (UNSW HREC)
Ethics committee address [1] 307906 0
UNSW Sydney
Research Ethics and Compliance Support (RECS)
Rupert Myers Building
Kensington
Sydney
NSW 2033
Ethics committee country [1] 307906 0
Australia
Date submitted for ethics approval [1] 307906 0
23/11/2020
Approval date [1] 307906 0
01/02/2021
Ethics approval number [1] 307906 0
HC200970

Summary
Brief summary
Approximately 4.1 million Australian adults suffer from hypertension, which was estimated to cause 26,000 deaths in Australia in 2017. Excess dietary salt consumption is a leading cause of high blood pressure, and dietary guidelines specifically recommend the avoidance of foods high in salt for blood pressure lowering. Yet, current individual-based education and clinical counselling to reduce salt intakes has shown limited effectiveness, is resource intensive, costly, and has limited reach. Hypertensive patients in Australia currently consume on average ~10g salt per day, nearly twice the World Health Organisation recommended maximum; with most (~80%) dietary salt derived from eating packaged and processed foods. Thus, innovative strategies are urgently needed to help hypertensive patients reduce their dietary salt intake.

The overall goal of this research is to determine the effectiveness of a novel, scalable, and sustainable salt reduction intervention (online grocery shopping, OGS) for lowering blood pressure (BP) amongst patients with hypertension. We will do this by conducting a large-scale randomised controlled trial (RCT) using an online grocery shopping intervention designed specifically for Woolworths, Australia’s largest online grocery retailer. The OGS will be provided to the study participants as a web-browser application, such that every time participants purchase groceries online, OGS will provide immediate on-screen, interpretive (i.e. colour-coded symbol) nutrition information and specific suggestions for lower salt alternatives. The personalised approach – consumers can maintain their usual dietary patterns and are guided to choose similar, but lower-salt alternative products – offers flexibility and caters to personal preferences.

If this intervention demonstrates even a 2 mmHg BP lowering effect, then it would be meaningful because 2 mmHg lower BP translates into an approximately 10% reduction in premature cardiovascular disease (CVD) amongst hypertensive patients. There is currently no other platform that could improve dietary behaviours more rapidly to reduce BP amongst Australians. The OGS online grocery shopping intervention has the potential to have a major effect on BP control and prevention of CVD in Australia and globally.

Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 108886 0
A/Prof Jason Wu
Address 108886 0
The George Institute for Global Health
Level 5, 1 King St
Newtown
NSW 2042
Country 108886 0
Australia
Phone 108886 0
+61 2 8052 4648
Fax 108886 0
Email 108886 0
[email protected]
Contact person for public queries
Name 108887 0
A/Prof Jason Wu
Address 108887 0
The George Institute for Global Health
Level 5, 1 King St
Newtown
NSW 2042
Country 108887 0
Australia
Phone 108887 0
+61 2 8052 4648
Fax 108887 0
Email 108887 0
[email protected]
Contact person for scientific queries
Name 108888 0
A/Prof Jason Wu
Address 108888 0
The George Institute for Global Health
Level 5, 1 King St
Newtown
NSW 2042
Country 108888 0
Australia
Phone 108888 0
+61 2 8052 4648
Fax 108888 0
Email 108888 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 have not obtained ethical approval for individual participant data to be publicly shared. Furthermore we are not obtaining consent from participants to make their individual participant data publicly available. Only study investigators will have access to de-identified individual participant data, as approved by ethics.


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
10734Ethical approval  [email protected] 381457-(Uploaded-17-02-2021-16-08-36)-Study-related document.pdf



Results publications and other study-related documents

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

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseProtocol for a novel sodium and blood pressure reduction intervention targeting online grocery shoppers with hypertension - the SaltSwitch Online Grocery Shopping randomized trial.2022https://dx.doi.org/10.1016/j.ahj.2022.06.007
N.B. These documents automatically identified may not have been verified by the study sponsor.