Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12613000875707
Ethics application status
Approved
Date submitted
2/08/2013
Date registered
6/08/2013
Date last updated
7/08/2013
Type of registration
Retrospectively registered

Titles & IDs
Public title
Consumption of fish oil and a Mediterranean influenced antioxidant diet on telomere length in older Australians:
Adherence and feasibility from a pilot study
Scientific title
Adherence and feasibility following consumption of fish oil or a Mediterranean influenced antioxidant diet: a pilot study
Secondary ID [1] 282951 0
NIL
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
At risk of cardiovascular disease 289776 0
Condition category
Condition code
Cardiovascular 290121 290121 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
12 week intervention assessing a Mediterranean influenced antioxidant diet (MAx) in which participants were provided 15g walnuts, 7.5g hazelnuts, and 7.5g almonds per day, pre-packed into weekly allowances, and 20ml virgin olive oil per day; commercially available from a large supermarket chain in Australia.
Intervention code [1] 287656 0
Behaviour
Intervention code [2] 287683 0
Prevention
Comparator / control treatment
12 week intervention assessing a fish oil capsule supplemented diet (provided nine capsules per day), with either higher dose n-3 PUFA (~1.5g EPA and 1g DHA), OR a lower dose n-3 PUFA (containing 10% of the active dose; control).
Control group
Active

Outcomes
Primary outcome [1] 290152 0
Adherence to fish oil capsules through fish oil diaries that recorded daily capsule consumption, adverse reactions, and reasons for missed doses.
Timepoint [1] 290152 0
Baseline and 12 weeks
Primary outcome [2] 290153 0
Adherence to the MAx diet through a validated Mediterranean diet score, self-reported daily diaries stating weekly nut consumption, and self-reported remaining olive oil.
Timepoint [2] 290153 0
Baseline, 6 weeks and 12 weeks
Secondary outcome [1] 304025 0
Telomere length measured in peripheral blood mononuclear cells isolated from whole blood and analysed using the qPCR technique.
Timepoint [1] 304025 0
Baseline and 12 weeks.
Secondary outcome [2] 304065 0
Telomerase activity measured using the repeat amplification protocol (TRAPeze 'registered trademark' ELISA Telomerase Detection Kit)
Timepoint [2] 304065 0
Baseline and 12 weeks

Eligibility
Key inclusion criteria
(1) be aged greater than or equal to 60 years; and (2) have any one of the following conditions (indicating increased risk for CVD: i. diabetes; ii. diagnosed familial hypercholesterolaemia; iii. systolic blood pressure greater than or equal to 180 mmHg or diastolic blood pressure greater than or equal to 110 mmHg; iv. serum total cholesterol greater than 7.5 mmol/L or any two of the following: i. current smoker; ii. waist circumference (greater than or equal to 94 cm men; greater than or equal to 80 cm women); iii. BMI (greater than or equal to 25.0 kg/m^2); iv. family history of CVD; and 3) a low intake of fish (less than 1 serving per week) or self-report to consume nuts and olive oil in amounts lower than the proposed Mediterranean style diet; (4) willing to consume 9 fish oil capsules per day or follow a diet containing foods high in antioxidants; (5) able to provide written informed consent; and (6) able to attend clinic visits at Flinders Medical Centre.
Minimum age
60 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
(1) unwilling to comply with study protocol; (2) diagnosed cardiovascular disease or suffered a CV event; (3) currently on a weight loss diet or actively trying to lose weight; (4) allergies to fish/seafood or components of the Mediterranean diet (e.g. nuts); (5) intake of anti-inflammatory medications on a regular basis or if an acute intake, within 1 week of clinic screening visit; and (6) currently taking fish oil.

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)
Participants will be randomized into one of three groups. Group 1 will follow a Mediterranean influenced antioxidant diet (provided 15g walnuts, 7.5g hazelnuts, and 7.5g almonds per day, pre-packed into weekly allowances, and 20ml virgin olive oil per day; commercially available from a large supermarket chain in Australia). Group 2 and Group 3 will consume a fish oil capsule supplemented diet (they will be provided with 9 capsules per day; Melrose, Australia, L156237), with either higher dose n-3 PUFA (~1.5g EPA and 1g DHA), or lower dose n-3 PUFA (containing 10% of the active dose; control). The contents of the fish oil capsules will be double blinded to participants and all study staff.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation schedule will be devised by an independent statistician using ralloc.ado version 3.6.1 in Strata version 11.1. Blocks of size 6, 9, and 12 were chosen at random and treatment allocations were randomly permuted and balanced within blocks.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety
Statistical methods / analysis
Statistical analyses will be performed using SPSS (SPSS 17.0 for Windows, SPSS Inc. Chicago, IL, USA). All baseline data were normal and were expressed as mean (+/-SD) values if continuous and frequency (%) if categorical. Comparisons between groups at baseline were made using the one way analysis of variance (ANOVA; with Tukey’s post hoc test) for independent groups for continuous variables and chi square tests for categorical variables. The level of significance was set at P<0.05 and two tailed P values were used.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
16/07/2012
Actual
27/07/2012
Date of last participant enrolment
Anticipated
Actual
14/01/2013
Date of last data collection
Anticipated
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA
Recruitment hospital [1] 1387 0
Flinders Medical Centre - Bedford Park
Recruitment postcode(s) [1] 7248 0
5042 - Bedford Park

Funding & Sponsors
Funding source category [1] 287727 0
Self funded/Unfunded
Name [1] 287727 0
Country [1] 287727 0
Primary sponsor type
University
Name
Flinders University
Address
Flinders Medical Centre
Nutrition and Dietetics
Flinders Drive, Bedford Park
SA 5042
Country
Australia
Secondary sponsor category [1] 286456 0
None
Name [1] 286456 0
Address [1] 286456 0
Country [1] 286456 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 289683 0
Southern Adelaide Clinical Research Ethics Committee
Ethics committee address [1] 289683 0
Ethics committee country [1] 289683 0
Australia
Date submitted for ethics approval [1] 289683 0
Approval date [1] 289683 0
15/06/2012
Ethics approval number [1] 289683 0
224.12

Summary
Brief summary
Traditional risk markers of CVD include blood lipids, inflammatory markers, and endothelial function. However, shorter telomeres have recently been associated with increased levels of C-reactive protein, being overweight and obese, and increased odds for developing CHD, when measured in peripheral blood mononuclear cells.
Anti-inflammatory dietary habits have been associated with increased telomere length. Specifically, a low fat, high antioxidant diet, with an emphasis on high fruit, vegetable, wholegrain and legume intake, increased telomerase activity; and a small four week intervention of consumption of a Mediterranean diet was found to decrease the percentage of cells with telomere shortening. The Mediterranean diet is high in polyphenols, phytochemicals, and monounsaturated fatty acids that confers antioxidative properties to reduce oxidative stress and inflammation to protect the heart. Recent studies have observed that specific aspects of the diet such as nuts and/or olive oil is protective towards cardiovascular health, and may thus be extracted and incorporated into the diets of other populations. Thus, the association between shorter telomeres and CVD risk factors, and anti-inflammatory diets with telomere biology, suggest that components of diets with anti-inflammatory properties may reduce CVD risk by preventing the loss of telomere length and increasing telomerase activity. To date, no study has compared the effects of fish oil supplementation or a Mediterranean influenced Antioxidant (MAx) diet on telomere length and telomerase activity in the Australian population. Furthermore, while the tolerance and acceptability of fish oil has been studied, acceptability of Mediterranean dietary aspects in an Australian population has not been investigated in a randomised controlled trial. Therefore, investigation into this area is essential to assessing the feasibility of introducing these foods to the population due to the cardiovascular benefits that they accrue.
This pilot study aims to identify (1) the adherence to fish oil and a MAx diet in older Australians and thus feasibility of such dietary interventions, and (2) areas for improvement in study design to aid the development of a larger six month study with 210 participants, which will investigate the effects of these dietary interventions on telomere length and telomerase activity.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 41938 0
Dr Jessica Grieger
Address 41938 0
Flinders Medical Centre, Bedford Drive
Level 7, Nutrition and Dietetics
Bedford Park
SA 5042
Country 41938 0
Australia
Phone 41938 0
+61 8 8204 7075
Fax 41938 0
Email 41938 0
[email protected]
Contact person for public queries
Name 41939 0
Dr Jessica Grieger
Address 41939 0
School of Paediatrics and Reproductive Health
Robinson Institute
Lyell McEwin Hospital
Haydown Road, Elizabeth Vale, SA 5112
Country 41939 0
Australia
Phone 41939 0
+61 8 8313 2132
Fax 41939 0
Email 41939 0
[email protected]
Contact person for scientific queries
Name 41940 0
Dr Jessica Grieger
Address 41940 0
School of Paediatrics and Reproductive Health
Robinson Institute
Lyell McEwin Hospital
Haydown Road, Elizabeth Vale, SA 5112
Country 41940 0
Australia
Phone 41940 0
+61 8 8313 2132
Fax 41940 0
Email 41940 0
[email protected]

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No Supporting Document Provided



Results publications and other study-related documents

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