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Trial registered on ANZCTR


Registration number
ACTRN12613000857707
Ethics application status
Approved
Date submitted
18/06/2013
Date registered
2/08/2013
Date last updated
19/11/2018
Date data sharing statement initially provided
19/11/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
The Preview Study Australia: prevention of diabetes through lifestyle intervention and population studies in Europe and around the world.
Scientific title
The preview study is a randomised, controlled, multi-centre, international clinical trial of 2 types of diet and 2 exercise strategies (4 arms in total) for the prevention of type 2 diabetes in overweight or obese volunteers at high risk of diabetes.
Secondary ID [1] 282693 0
Project no. 312057
Seventh Framework Programme
Secondary ID [2] 282911 0
NTOCO177-7893 WHOrganisation Trial No.
Universal Trial Number (UTN)
Trial acronym
PREVIEW- PREVention of diabetes In Europe and Worldwide
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 289406 0
Diabetes 289407 0
Condition category
Condition code
Metabolic and Endocrine 289732 289732 0 0
Diabetes
Diet and Nutrition 290050 290050 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study consists of two distinct parts, i.e an 8 week weight reduction period followed by a 148 week randomized weight maintenance, diet and exercise intervention.
All participants are put on an energy restricted low calorie diet (LCD) consisting of 800-1000kcal/d with a target macronutrient composition of 15-20% of total energy from fat, 35-40% from protein and 45-50% from carbohydrate. The participants will be provided with nutritionally complete meal replacement LCD products (4 sachets per day) supplied by Cambridge Weight Plan U.K. for 8 weeks, aiming for a minimum 8% reduction in weight.
The post-LCD phase aims to prevent Type 2 Diabetes by modifying lifestyle factors such as diet and physical activity to promote healthy weight maintenance. The participants are randomized into two different diet interventions and two exercise interventions for a total of 148 weeks. The 2 diet interventions are:
1. Moderate Protein (MP) Diet: protein 15% of total energy intake (E%), carbohydrates 55 E%, and a dietary glycaemic index (GI) greater than 56;
2. High protein (HP) Diet: protein 25 E%, carbohydrates 45 E%, GI less than 55.
Both diet interventions focus on healthy food items to be consumed ad libitum with respect to energy. A dietitian will educate participants on portion sizes, healthy eating habits to achieve the macronutrient and GI prescription and self-monitoring in order to maintain weight loss.
The two exercise interventions are:
1. Moderate Intensity (MI): 60-75% of maximal heart rate (HRmax) 150mins total/week (frequency 3-5 times) e.g. brisk walking.
2. High intensity (HI): 76-90% HRmax for 75 mins total/week (frequency 2-3 times) e.g. running.
In the first weeks of the weight maintenance phase the participants will work with an exercise physiologist to plan their physical activity program including a 4week period where exercise levels are slowly introduced to reach the intended prescribed program.
Intervention code [1] 287353 0
Early detection / Screening
Intervention code [2] 287354 0
Prevention
Intervention code [3] 287355 0
Lifestyle
Comparator / control treatment
All participants are randomised into one diet and one exercise group, therefore there will be four intervention groups (MP-MI, MP-HI, HP-MI and HP-HI).
Control group
Active

Outcomes
Primary outcome [1] 289822 0
The incidence of type-2 diabetes in the high protein versus medium protein diet will be measured 3 years after the baseline and based on the WHO/IDF criteria:
1. Fasting plasma glucose greater than 7.0mmol/l
2. 75g oral glucose tolerance test (OGTT) with FBG greater than 7.0 mmol/l and/or 2 hour plasma glucose greater than 11.1 mmol/l or,
3. Glycated haemoglobin (HbA1c) greater than 6.5%, or
4. random plasma glucose greater than 11.1 mmol/l in the presence of classical diabetes symptoms.
Timepoint [1] 289822 0
OGTTs and blood tests will be conducted at baseline, 6, 12, 24 and 36 months to test for type-2 diabetes. Patients will also be requested to report any adverse events or change in medical status. Participants will be asked about any adverse events at group meetings at 2, 4, 6 weeks and 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 18, 24, 30 and 36 months and informal phone/email contact in the last 2 years between visits.
Secondary outcome [1] 303319 0
Thee secondary outcomes will be tested against the four intervention groups based on WHO/IDF criteria (adjusted for diet). The following parameter will be examined: change in HbA1c as a measure of average glucose levels.
Timepoint [1] 303319 0
HbA1c will be measured at baseline, 6, 12, 24 and 36 months.
Secondary outcome [2] 303884 0
Change in insulin sensitivity will be examined in the four intervention groups.
Timepoint [2] 303884 0
Change in HbA1c, as a measure of average blood glucose levels and OGTTS will be conducted at baseline, 6, 12, 24 and 36 months to test for insulin sensitivity.
Secondary outcome [3] 303904 0
Change in anthropometry i.e. change in body weight (scales), body fat mass (DEXA scan), and measured waist, hip and thigh circumference. The proportion of subjects maintaining at least 0, 5, or 10% weight loss relative to initial body weight will be compared in the four intervention groups.
Timepoint [3] 303904 0
Anthropometry will be measured at baseline, 6, 12, 24 and 36 months .
Secondary outcome [4] 303905 0
Change in the risk factors for cardiovascular disease such as blood pressure, lipid profile, c-reactive protein and liver enzymes, will be compared in the four intervention groups.
Timepoint [4] 303905 0
Blood tests and blood pressure measurements will be conducted at baseline, 6, 12, 24 and 36 months to test for type-2 diabetes.
Secondary outcome [5] 303906 0
Changes in perceived quality of life and workability will be compared in the four intervention groups using questionnaires,(WHOQOL-BREF (The WHOQOL Group 1998) and (Work Ability Index (WAI:Tuomi et al 1998), respectively .
Timepoint [5] 303906 0
Questionnaires will be conducted at baseline, 6, 12, 24 and 36 months and compared in the four intervention groups..
Secondary outcome [6] 303949 0
Assessment sleep and chronic stress in the four intervention groups, using the Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI) questionnaires.
Timepoint [6] 303949 0
The questionnaires will be conducted at baseline, 6 12, 24 and 36 months.

Eligibility
Key inclusion criteria
1. Body Mass Index greater than 25kg/m2
2. WHO/IDF (International Diabetes Foundation) definition of pre-diabetes: Impaired fasting glucose (IFG) 5.6-6.9mmol/l or Impaired glucose tolerance (IGT) Venous plasma glucose concentration of 7.8-11.0 mmol/l at 2 hrs after oral administration of 75g glucose (oral glucose tolerance test (OGTT)), with fasting plasma glucose less than 7.0 mmol/l.
Minimum age
25 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Diabetes (other than gestational diabetes).
2. Systolic blood pressure above 160 mmHg and/or diastolic blood pressure above 100mmHg
3. Previous bariatric surgery
4. Significant health problems

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)
Allocation will be concealed. Potential participants will be recruited using a variety of ways i.e. newspaper advertisements, written and electronic media (website questionnaire), local obesity and diabetes associations and direct contact with primary and occupational health care providers. Individuals will be invited to contact the site-centre by email, telephone or SMS. Individuals will be contacted by phone or email for a short pre-screening interview where most inclusion and exclusion criteria will be queried. Based on the interview potential participants will be sent a written description of the study and when written consent is obtained invited to a laboratory-screening day. All potential participants will sign a consent form before laboratory screening begins. Measurements of height, weight, resting blood pressure, an ECG (people over 55 years) and a simplified OGTT consisting of a fasting blood glucose and a 2 hour blood glucose (after 75g glucose) will be used to assess subjects eligibility. Subjects will be informed of their eligibility. The participant will be randomized into one of the four intervention groups by a central computer generated randomization system at the central administration site in Denmark. Randomization of all the participants is done by stratifying the participants according to age-group and sex (men, women). The randomization is done in blocks to ensure an equal number of participants in each group. The randomization will not be revealed to the group until week 9 of the study (after their LCD phase).
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Subject numbers will be generated at the central study site at the University of Helsinki. All data will be collected using an electronic case record form (eCRF) based on the electronic data capture system OpenClinica. A screening number and the date of birth identify the subjects on the eCRF. The randomization number/code is via a web application linked to OpenClinica. Randomization is done by stratifying the subjects according to age group and sex. It will be done in blocks in order to ensure an equal number of participants in each group.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Published data has demonstrated among patients who completed the study the 3 year incidence of type 2 diabetes in adults aged over 40 with a diabetes risk score AUSDIAB OVER 6 is 21%. Our main power calculations are based on two intervention arms (i.e. HP vs MP diet). We hypothesize a risk reduction of 25% in the MP group and will reduce the diabetes incidence to 15.8%. In the HP group the risk reduction, we hypothesize, will achieve a 50% risk reduction to 10.5% at 3 years.
Using these assumptions a conservative estimate of the sample size required to detect this difference in incidence (15.8% vs 10.5%) is at least 649 per arm or 1298 participants in total (for a two-sided comparison with a power of 80% and alpha of 0.05). We estimate a 30% drop-out rate (similar to DIOGenes) during the 148 week intervention period.
Thus, we need at least 1860 subjects (across all study centres) starting the intervention. To further allow for a drop-out after inclusion and for subjects not losing 8% weight during the 8 week weight loss period (estimated 25%), a total of about 2472 subjects will be recruited.
The consortium will therefore recruit a total of 2,500 participants at high risk of diabetes, from the 8 centres ( a total of 310-315 in each centre) to initiate the weight reduction period.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
30/08/2013
Actual
21/01/2014
Date of last participant enrolment
Anticipated
31/01/2014
Actual
27/02/2015
Date of last data collection
Anticipated
1/06/2018
Actual
30/06/2018
Sample size
Target
310
Accrual to date
Final
195
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 287466 0
University
Name [1] 287466 0
The University of Sydney
Country [1] 287466 0
Australia
Primary sponsor type
University
Name
The University of Sydney
Address
Level 6 Charles Perkins Centre D 17
The University of Sydney
NSW 2006
Country
Australia
Secondary sponsor category [1] 286210 0
Other Collaborative groups
Name [1] 286210 0
National Health & Medical Research Council - European Union (NHMRC-EU) Collaborative Project.
Address [1] 286210 0
NHMRC – European Union Collaborative Research Grants
Research Programs
GPO Box 1421
CANBERRA ACT 2601
Country [1] 286210 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 289441 0
Office of Research Integrity/Research Portfolio The University of Sydney
Ethics committee address [1] 289441 0
Office of Research Integrity/Research Portfolio,
Level 6 Jane Foss Russell Building G02
The University of Sydney
NSW 2006
Ethics committee country [1] 289441 0
Australia
Date submitted for ethics approval [1] 289441 0
27/06/2013
Approval date [1] 289441 0
14/07/2013
Ethics approval number [1] 289441 0
2013/535

Summary
Brief summary
The primary goal of the Preview intervention study is to identify the most efficient lifestyle pattern for the prevention of type-2 diabetes in a population of pre-diabetic overweight or obese individuals (i.e those at high risk of diabetes). This will be done by conducting a clinical randomized intervention trial of 3 years duration in a total 310 pre-diabetic adults in Australia.
Trial website
preview.ning.com/sydney
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 40862 0
Prof Jennie Brand Miller
Address 40862 0
School of life and Environmental Sciences Level 6 Charles Perkins Centre, D17, University of Sydney, NSW 2006.
Country 40862 0
Australia
Phone 40862 0
+61 2 9351 3759
Fax 40862 0
+61 2 9036 3024
Email 40862 0
[email protected]
Contact person for public queries
Name 40863 0
Roslyn Muirhead
Address 40863 0
PREVIEW Study, Level 6 Charles Perkins Centre D17 The University of Sydney, Sydney NSW 2006
Country 40863 0
Australia
Phone 40863 0
+61 0286271936
Fax 40863 0
+61 2 90363176
Email 40863 0
[email protected]
Contact person for scientific queries
Name 40864 0
Ros Muirhead
Address 40864 0
PREVIEW Study, Level 6 Charles Perkins Centre D17 The University of Sydney, Sydney NSW 2006
Country 40864 0
Australia
Phone 40864 0
+61 478 472 170
Fax 40864 0
Email 40864 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Undecided
No/undecided IPD sharing reason/comment
This study is part of an international study funded by the European Union and the data is still being analysed. The Principal Investigators have yet to decide on how the data will be archived and how much would be available, and to whom.


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
312Other    https://preview.ning.com



Results publications and other study-related documents

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