Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12617000510347
Ethics application status
Approved
Date submitted
5/04/2017
Date registered
7/04/2017
Date last updated
11/10/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of intermittent energy restriction on the way blood vessels work
Scientific title
The effect of fasting on endothelial function in healthy adults or adults with type 2 diabetes.
Secondary ID [1] 291624 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cardiovascular Disease 302748 0
Obesity 302762 0
Condition category
Condition code
Cardiovascular 302264 302264 0 0
Other cardiovascular diseases
Diet and Nutrition 302277 302277 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
In a randomized cross-over study including 32 adults men and women an intermittent energy restriction regime asking participants to follow a very low calorie diet (2100kJ for women and 2500kJ for men) for two days per week before returning to their normal eating habits for the other 5 days will be prescribed. This is commonly known as the 5:2 diet. Participants will be asked to attend the Sansom Institute for Health Research Clinical Trials Facility on four separate occasions. Body height (once only), body weight & and blood vessel function (using techniques of applying blood pressure cuffs to you upper arm and thigh and an ultrasound of the artery above your elbow) will be measured as part of an initial screening visit participants will also meet with a dietitian who will assess eligibility for the study & provide information about the diet. Dietary compliance will be measured via weighed food diary (weighing everything you eat) for the duration of each fast day during the trial (8 days). The fasting days are required to be consecutive, and the 5:2 regime is to be followed continuously for 4 weeks. Visit 2 will occur two weeks later and will involve a check in with the dietitian to check dietary compliance. The following week participants will be asked to return for a visit following 2 fast days or 2 ad libitum eating days (this will be discussed in visit 2) for assessment of weight and blood vessel function. Visit 4 they will return for measurements as taken in visit 3 following the reverse dietary condition. The order of assessment for visits 3 and 4 is randomised using an online randomisation generator. Participants will also have their liver size measured via ultrasound at the baseline and last visit of the trial. The study runs for a total of 4 weeks.
Intervention code [1] 297698 0
Lifestyle
Intervention code [2] 297710 0
Treatment: Other
Comparator / control treatment
The comparator is testing individuals following 2 ad libitum eating days.
Control group
Active

Outcomes
Primary outcome [1] 301677 0
Investigate the effect of two fasting days compared to two ad libitum eating days on blood vessel function. Blood vessel function will be assessed by Flow Mediated Dilatation, measured via brachial ultrasound.
Timepoint [1] 301677 0
Weeks 3 and 4 of the intervention following 2 fast days or 2 ad libitum eating days depending on the randomisation the participant has received.
Secondary outcome [1] 333534 0
Determine changes in serum lipids.
Timepoint [1] 333534 0
Weeks 3 and 4 of the intervention following 2 fast days or 2 ad libitum eating days depending on the randomisation the participant has received.
Secondary outcome [2] 333564 0
Determine changes in plasma glucose.
Timepoint [2] 333564 0
Weeks 3 and 4 of the intervention following 2 fast days or 2 ad libitum eating days depending on the randomisation the participant has received.
Secondary outcome [3] 333565 0
Determine Changes in Insulin.
Timepoint [3] 333565 0
Weeks 3 and 4 of the intervention following 2 fast days or 2 ad libitum eating days depending on the randomisation the participant has received.
Secondary outcome [4] 339690 0
Determine changes in liver size. Participants will have a very short liver ultrasound (less than 5 minutes) in which two pictures of the liver will be taken. Participants will be placed supping on an ultrasound table with their body tilted 45 degrees to the left in a direction away from the sonographer. The participants skin will be exposed from their waist to their xiphisternum. Measurements will be made from the images later.
Timepoint [4] 339690 0
Measure liver size at baseline and at week 4 of the trial.

Eligibility
Key inclusion criteria
BMI > 18.5 kg/m
Aged 18 - 75 years
Not pregnant or breast feeding
Participant reports they are healthy or have type 2 diabetes managed by diet alone or stable dose metformin
Minimum age
18 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Drinking more than 5 standard drinks per day and unable/unwilling to stop
Participant reports they are unwell
Participating in any ongoing dietary studies
Eating out more than once a fortnight and unable/unwilling to stop for the duration of the study

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)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
Intervention assignment
Crossover
Other design features
Phase
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
23/03/2017
Date of last participant enrolment
Anticipated
30/06/2017
Actual
19/07/2017
Date of last data collection
Anticipated
31/07/2017
Actual
23/08/2017
Sample size
Target
32
Accrual to date
Final
36
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 296114 0
University
Name [1] 296114 0
University of South Australia
Country [1] 296114 0
Australia
Primary sponsor type
University
Name
University of South Australia
Address
GPO Box 2471, Adelaide 5001
Country
Australia
Secondary sponsor category [1] 295011 0
None
Name [1] 295011 0
Address [1] 295011 0
Country [1] 295011 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297368 0
University of South Australia
Ethics committee address [1] 297368 0
GPO Box 2471, Adelaide 5001
Ethics committee country [1] 297368 0
Australia
Date submitted for ethics approval [1] 297368 0
22/11/2016
Approval date [1] 297368 0
19/01/2017
Ethics approval number [1] 297368 0
0000036095

Summary
Brief summary
The vascular endothelium plays an important role in the regulation in several important bodily processes, including arterial tone, thrombosis, and inflammation. Dysfunction in the endothelium can lead to the development of atherosclerotic lesions, a pathophysiological link to acute cardiovascular disorders. A common condition associated with endothelial dysfunction is obesity. Current research suggests that the mechanism of obesity-induced endothelial dysfunction may be multifactorial, as excess adipose tissues has been shown to induce several metabolic changes which have the potential to interfere with normal endothelial function. A recent meta-analysis (Joris, P J et al. 2015) of human studies on the effects of weight loss on FMD of the brachial artery reported that weight loss increased FMD vs. control by 3.29%. It also estimated that each 10kg decrease in body weight increased fasting FMD by 1.11%. Researchers highlighted that effects may depend on subject characteristics, type of weight-loss treatment, and dietary composition. Within the studies included in the meta-analysis, increases in FMD were larger in the higher weight-loss group when subjects consumed low-fat diets compared with low-carbohydrate diets. What has not been investigated however, in this meta-analysis or indeed in any RCT to date, is whether the impact of changed dietary composition (and resulting hypocaloric conditions) through intermittent energy restriction results in a change in FMD. Accordingly, the current study is designed to investigate the effect of intermittent energy restriction on endothelial function, relative to habitual intakes. This research will add value to the scientific field by adding to the existing literature targeting intermittent energy restriction and its potential health benefits. primary aim of this study is to investigate the effect of two fasting days compared to two ad libitum eating days on blood vessel function. Secondary aim is to determine changes in, serum lipids, plasma glucose and insulin. We hypothesize that individuals will have similar endothelial function following two fasting days compared to two ad libitum eating days.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 73834 0
Mrs Michelle Headland
Address 73834 0
University of South Australia
GPO Box 2471, Adelaide 5001
Country 73834 0
Australia
Phone 73834 0
+61 438 7020 99
Fax 73834 0
Email 73834 0
[email protected]
Contact person for public queries
Name 73835 0
A/Prof Jennifer Keogh
Address 73835 0
University of South Australia
GPO Box 2471, Adelaide 5001
Country 73835 0
Australia
Phone 73835 0
+61 8 830 22579
Fax 73835 0
Email 73835 0
[email protected]
Contact person for scientific queries
Name 73836 0
A/Prof Jennifer Keogh
Address 73836 0
University of South Australia
GPO Box 2471, Adelaide 5001
Country 73836 0
Australia
Phone 73836 0
+61 8 830 22579
Fax 73836 0
Email 73836 0
[email protected]

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No Supporting Document Provided



Results publications and other study-related documents

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