Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12614000395639
Ethics application status
Approved
Date submitted
4/03/2014
Date registered
10/04/2014
Date last updated
11/03/2019
Date data sharing statement initially provided
11/03/2019
Date results information initially provided
11/03/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
The BROAD study. A trial using the whole-foods, plant-based diet in a community programme for people with obesity, or overweight with ischaemic heart disease or diabetes
Scientific title
The BROAD study. A randomised controlled trial using the whole-foods, plant-based diet in a 12-week community-based programme for people with obesity, or overweight with ischaemic heart disease or diabetes
Secondary ID [1] 284201 0
Nil
Universal Trial Number (UTN)
U1111-1153-4792
Trial acronym
BROAD Study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Prevention and treatment of chronic disease using lifestyle modification 291197 0
Ischaemic heart disease 291198 0
Diabetes mellitus type II 291199 0
Overweight and obesity 291200 0
Condition category
Condition code
Cardiovascular 291535 291535 0 0
Coronary heart disease
Metabolic and Endocrine 291536 291536 0 0
Diabetes
Diet and Nutrition 291537 291537 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised controlled trial will determine the benefit of comprehensive lifestyle changes in a sample of New Zealanders with common chronic diseases. Participants will have raised body mass index (BMI) greater than or equal to 30 or BMI greater than or equal to 25 and either ischaemic heart disease (IHD) or type 2 diabetes mellitus (diabetes). Participants who are assigned to the intervention group will participate in a programme of lifestyle change (incorporating a low-fat pure vegetarian diet) for 3 months, and those assigned to the control group will receive their usual-care.

A brief, standardised personality assessment will help identify any personality traits associated with adherence. This trial will evaluate the efficacy of a lifestyle intervention incorporating a low-fat, pure vegetarian diet for New Zealanders on a broad range of health determinants and risk factors. As far as we are aware it will be the first trial of such a lifestyle intervention outside of the USA.

The intervention involves attendance of twice weekly evening sessions of 2.5 hour duration designed to enable participants to learn about the relation of food and nutrition to a range of diseases and recognized disease risk factors. These will include brief lectures, practical demonstrations, videos, cooking classes, and small group work. Participants will also be provided with educational materials, some food items, and some items of kitchen equipment in order to facilitate the lifestyle changes advocated in the intervention. They may be expected to complete some small assignments, recordings, or ‘homework’ activities between evening sessions. This study intervention will differ significantly from lifestyle interventions previously studied by focusing on the ‘how to’ rather than the ‘why to’.

Ongoing adherence will be monitored through the use of food recall diaries monitored monthly for three months in the intervention group, then at months three and six after study initiation. Diet recall will be performed for the control group at study initiation and at six months after study initiation.

Evening sessions will run for three months total, with an additional weekend together for an ‘immersion’ in the lifestyle changes and team-building 2 weeks into the programme. The aim of the intervention is to help participant learn and teach one another how to make positive changes in their dietary (and other lifestyle) behaviours so that they can reduce risk of their established diseases progressing (potentially reversing these if related to lifestyle factors) and prevent developing new diseases.

The lifestyle intervention will advocate a nutritionally complete dietary plan where participants follow a low-fat (10-15% calories from fat) ‘plant-based’ diet. The diet includes every type of fruit, vegetable and grain. Whole grains are encouraged. Very high-fat plant-foods such as nuts, avocados, and olives are discouraged, as are highly-processed foods. Restricting use of sugar and salt will be encouraged as will minimizing or cessation of caffeine. The diet specifically excludes meat (of any kind, including chicken and fish), dairy (including cheese, yoghurt), and refined oils (such as canola, olive, or sunflower oil). Participants will be encouraged to eat until satiation from the foods included in the diet, without regard for total energy intake (i.e. ‘not counting calories’). A very small amount of B12 supplementation will be provided to all participants following this diet, to ensure adequate intake.

Vitamin B12 supplementation will be provided at no cost to those in the intervention group, in the form of drops containing 50mcg per dose, which should be taken daily.

In summary, this study will be conducted by doctors providing participants (and when necessary their families) with an intervention in their community in the form of education on the management of chronic disease by dietary and lifestyle changes. Those conducting the study are also the main investigators.

Update Nov 2015, post initial study extension:
Participants and researchers have agreed to continue approximately 6 further intervention sessions from November 2015 to February 2016, for the participants of both the first randomised group (who are at month 15 of the research) of participants, and the second non-randomised group (who are at month 8 of the research). These sessions will be further meetings of approximately 2 hours length in which we will discuss sustaining the lifestyle changes and providing further support to participants. The participants will each be provided with a cookbook; Prevent and Reverse Heart Disease cookbook, or Happy Herbivore Light and Lean. The Ethics Committee has been informed of these minor additions to the intervention.
Intervention code [1] 288810 0
Lifestyle
Intervention code [2] 289065 0
Prevention
Intervention code [3] 289066 0
Treatment: Other
Comparator / control treatment
Standard treatment was provided for the control group during the first 6 months of the programme, under the usual care provided by general practitioners.

After the initial intervention was offered to the lifestyle change group, significant differences from baseline were seen from preliminary analysis. This included primary end points. As such, the control group was offered to undertake the lifestyle intervention starting April 14th 2015.

The ethics committee that granted original approval was updated prior to the start of this second stage of the intervention and granted approval for the extension of data collection (see data end points).
Control group
Active

Outcomes
Primary outcome [1] 291861 0
Primary 1. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in a decrease in cholesterol?
Timepoint [1] 291861 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Primary outcome [2] 291862 0
Primary 2. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in a decrease in BMI?
Timepoint [2] 291862 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [1] 307684 0
Secondary 1. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in a decrease in cardiovascular risk factors?

Cardiovascular risk assessment will be measured through the Framingham Heart Study criteria, and also the New Zealand modified version of this, created by the New Zealand guidelines group.
Timepoint [1] 307684 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [2] 307685 0
Secondary 2. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in a decrease in cardiovascular events and progression to surgery (and associated transfers to higher level care)?

This will be measured by hospital records and from contact with the GP.
Timepoint [2] 307685 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [3] 307686 0
Secondary 3. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in a decrease in medication requirements/usage?


Medication usage will be assessed using the records available from the GP, and discussions with the patients to confirm this.
Timepoint [3] 307686 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [4] 307687 0
Secondary 4. Does the BROAD lifestyle intervention, compared with “treatment as usual” in the community setting, for patients with BMI greater than or equal to 30, OR BMI greater than or equal to 25 AND either ischaemic heart disease OR type 2 diabetes mellitus result in an improvement in quality of life?

This will be measured using the SF-36
Timepoint [4] 307687 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [5] 307688 0
Secondary 5. Are there measurable personality traits which predict adherence to the BROAD lifestyle intervention?

Personality traits will be measured using the Big Five Inventory (BFI)
Timepoint [5] 307688 0
Measured at 6, 12, 24 and 36 months from start of the intervention.
Secondary outcome [6] 307689 0
Secondary 6. Are there are other unexpected benefits or adverse effects from the BROAD lifestyle intervention?

This will be measured from adverse event reporting from the safety officer, GPs, and through informal qualitative interviewing with the participants throughout the study
Timepoint [6] 307689 0
Measured at 6, 12, 24 and 36 months from start of the intervention.

Eligibility
Key inclusion criteria
Participants self-identify (with assistance from their GP) as willing to undergo a lifestyle change, and have a diagnosis of raised body mass index (BMI) greater than or equal to 30 or BMI greater than or equal to 25 and either ischaemic heart disease (IHD) or type 2 diabetes mellitus (diabetes)

*Ischaemic heart disease: defined as a diagnosis of IHD confirmed by the patient’s GP as well as any one or more of the following: angina requiring medication; prior surgery including stents or coronary artery bypass grafting (CABG); a total cholesterol of >6 pre-treatment with statins; or pre-treatment hypertension as defined by >140 systolic, or >90 diastolic. See exclusion criteria for more information.

*Diabetes mellitus type II: defined as a diagnosis of type 2 diabetes confirmed by the patient’s GP as well as a previous diagnosis based upon findings consistent with the current New Zealand standards for type 2 diabetes: either both >50mmol/mol HbA1c and symptoms, or two repeat tests three months apart >50mmol/mol if no symptoms.

*Raised BMI: A current BMI greater than, or equal to 30kg/m2 is an entrance criteria in of itself, or participants can have a current BMI greater than or equal to 25kg/m2 and IHD or a BMI greater than or equal to 25kg/m2 and diabetes.

Patients must be able and willing to follow all instructions, including attending education sessions twice weekly (on Tuesday and Thursdays), must be able and willing to follow the intervention at home (i.e. be the primary cook, or have the primary cook of the household provide this food), and be aged between 35-70 years old. Participants must be willing to fill out a diet recall, undergo additional blood tests and measurements, and not adjust any additional supplements or remedies they may be taking during the study unless advised to do so by their GP or other doctors. Certain supplements may be stopped.

No healthy volunteers will be considered.
Minimum age
35 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
A patient will not be considered for participation if they meet any of the exclusion criteria. Patients with any of the following will be excluded for safety purposes:
* >50% stenosis in the left main coronary artery (if angiography has been performed)
* Coronary artery bypass grafting within 6 weeks
* Angioplasty within 6 months
* Chronic unresponsive congestive heart failure
* Malignant uncontrolled arrhythmias
* Myocardial infarction within 1 month
* Homozygous hypercholesterolaemia
* Hypotensive response to exercise

Furthermore, those with thyroid disease, life-threatening comorbidity, severe mental health issues, current smoking, alcohol or drug misuse, pregnancy or breastfeeding, or current adherence to a low fat, plant-based diet would be excluded. During the study, it may become necessary to exclude patients if they develop, or it is discovered they have one of the conditions listed above.

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)
A brief synopsis of the study purpose, intended intervention, and outcome measures will be presented to local general practitioners (GPs). GPs will be informed of the inclusion and exclusion criteria for participants and invited to discuss the study briefly with their patients. Participants will be provided with an information sheet from their GP and an invitation to register their interest with the researchers. Participants will be asked to rate their self-efficacy, reflecting perceived ability to successfully undertake a lifestyle change. Answers will be compared to a standard deviation from previous studies for the self-efficacy scale.

Once a patient has registered their interest, had their eligibility confirmed with their GP, and undergone the self-efficacy measure, patients will be invited to undergo further screening. Those who are eligible at this stage and remain interested in participating will then be contacted for an individual semi-structured interview, during which further information regarding their eligibility will be confirmed by a research assistant. Participants will at this point be asked to sign an information release form allowing the researchers to contact their GP to confirm any further details that may affect their eligibility. Once eligibility has been confirmed by the research team, patients will be invited to participate, and written consent sought.

Each will be randomised to either the intervention or control group by the physician co-researcher phoning the programme coordinator. Ultimately, this was done by listing participants by order of interview. Without providing identifying details to the public health physician, allocations were generated by computer programme and these were entered in by the research coordinator for each participant.

The GP of the participant will not be informed by the research team as to which group the participant is allocated in, but as this trial is not able to blind participants, the GP will be able to ask the participant directly.

The participants in the intervention group will then be contacted to attend group sessions held twice weekly during evenings at the same venue. Control group members will be contacted for further participation as appropriate.

Update post study extension:
After the initial lifestyle group competed the intervention, 10 individuals from the control group chose to participate in the next intervention. Those who were initially screened and interviewed but were unavailable to participate were offered an opportunity also and 11 form this group joined this group to make 21 participants. This group began the intervention on April 14th 2015.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A public health physician co-researcher generated allocations using a 1:1 sequence from a computer programme. Married, partnered and related participants were randomised together in place of the first person (a total of 5 pairs were randomised).

Stratification was not used, and allocations were not subsequently be changed.
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
Because of the nature of this study, participants will not be able to be blinded to their allocation into intervention or control groups.
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
The number of participants assumes that, conventionally, the study will have an 80% chance of demonstrating an effect at a confidence level of 95% (p<0.05) and is based around the magnitude of effects from previous studies overseas. The estimate of number of participants also includes a drop-out rate based on previous studies.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
11/06/2014
Actual
11/06/2014
Date of last participant enrolment
Anticipated
20/08/2014
Actual
14/08/2014
Date of last data collection
Anticipated
16/04/2018
Actual
31/07/2018
Sample size
Target
60
Accrual to date
Final
65
Recruitment outside Australia
Country [1] 5838 0
New Zealand
State/province [1] 5838 0
Gisborne

Funding & Sponsors
Funding source category [1] 288815 0
Charities/Societies/Foundations
Name [1] 288815 0
Tairawhiti Complementary and Traditional Therapies Research Trust
Country [1] 288815 0
New Zealand
Funding source category [2] 290975 0
Charities/Societies/Foundations
Name [2] 290975 0
Tairawhiti Community Services Trust
Country [2] 290975 0
New Zealand
Primary sponsor type
Individual
Name
Dr Nicholas Wright
Address
BROAD STUDY
PO BOX 2064
Gisborne
4040
Country
New Zealand
Secondary sponsor category [1] 287510 0
Individual
Name [1] 287510 0
Dr Luke Wilson
Address [1] 287510 0
BROAD STUDY
PO BOX 2064
Gisborne
4040
Country [1] 287510 0
New Zealand
Secondary sponsor category [2] 287511 0
Individual
Name [2] 287511 0
Dr Bruce Duncan
Address [2] 287511 0
421 Ormond Road, Gisborne Hospital, 4010, Gisborne
Country [2] 287511 0
New Zealand
Secondary sponsor category [3] 287512 0
Individual
Name [3] 287512 0
Dr Patrick McHugh
Address [3] 287512 0
421 Ormond Road, Gisborne Hospital, 4010, Gisborne
Country [3] 287512 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 290588 0
Northern B Health and Disability Ethics Committee
Ethics committee address [1] 290588 0
Health and Disability Ethics Committees
C/- Medsafe, Level 6, Deloitte House
10 Brandon St
PO Box 5013
Wellington
6011
Ethics committee country [1] 290588 0
New Zealand
Date submitted for ethics approval [1] 290588 0
10/03/2014
Approval date [1] 290588 0
28/05/2014
Ethics approval number [1] 290588 0

Summary
Brief summary
Our intervention aims to help patients learn and teach one another how to make positive changes in their dietary (and other lifestyle) behaviours. The intervention will advocate a nutritionally complete dietary plan where participants follow a low-fat ‘plant-based’ diet.

We hypothesise that those who participate in the BROAD intervention will lose weight, improve their diabetes control and have an improved heart health and quality of life.
Trial website
www.thebroadstudy.com
Trial related presentations / publications
1. Wright N, Wilson L, Smith M, Duncan B, McHugh P. The BROAD study: A randomised controlled trial using a whole food plant-based diet in the community for obesity, ischaemic heart disease or diabetes. Nutr Diabetes. 2017 Mar 20;7(3):e256.
Public notes

Contacts
Principal investigator
Name 46330 0
Dr Nicholas Wright
Address 46330 0
BROAD STUDY
PO BOX 2064
Gisborne
4040
Country 46330 0
New Zealand
Phone 46330 0
+64 4 496 5999
Fax 46330 0
Email 46330 0
[email protected]
Contact person for public queries
Name 46331 0
Dr Nicholas Wright
Address 46331 0
BROAD STUDY
PO BOX 2064
Gisborne
4040
Country 46331 0
New Zealand
Phone 46331 0
+64 4 496 5999
Fax 46331 0
Email 46331 0
[email protected]
Contact person for scientific queries
Name 46332 0
Dr Nicholas Wright
Address 46332 0
BROAD STUDY
PO BOX 2064
Gisborne
4040
Country 46332 0
New Zealand
Phone 46332 0
+64 4 496 5999
Fax 46332 0
Email 46332 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Already we have published our first dataset which included all available data from both groups (except in depth breakdown of the SF36 quality of life data)
When will data be available (start and end dates)?
Published online with our first publication, subsequent publications will also include datasets. Date first available 20 March 2017, and will be available in perpetuity.
Available to whom?
Public
Available for what types of analyses?
Up to individual researchers
How or where can data be obtained?
Public, free, website, cvs / xcel file


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 Wright N, Wilson L, Smith M, Duncan B, Mchugh P, W... [More Details]

Documents added automatically
No additional documents have been identified.