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Trial registered on ANZCTR


Registration number
ACTRN12612000325808
Ethics application status
Approved
Date submitted
20/03/2012
Date registered
21/03/2012
Date last updated
16/12/2015
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of genetic background on blood pressure response to dietary salt
Scientific title
To examine the effect of the CYP4F2 G1347A polymorphism on blood pressure and plasma and urinary 20-HETE responses to dietary salt in healthy overweight volunteers
Secondary ID [1] 280178 0
nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
metabolic syndrome 286112 0
Condition category
Condition code
Cardiovascular 286307 286307 0 0
Hypertension

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Healthy overweight men aged between 20 and 70 years and overweight healthy post-menopausal women less than 70yrs will give a blood sample from which DNA will be extracted. The DNA will be used to screen for two genetic polymorphisms called CYP4F2 G1347A and CYP4A11 T8590C, using a reverse transcription polymerase chain reaction. These polymorphisms are known to affect 20-HETE levels. A group that are carriers of the A allele of the CYP4F2 G1347A polymophism but who do not have the CYP4A11 T8590C polymorphism and a control group that have neither polymorphism will be studied. Baseline salt intake will be assessed by 24 hr urine collections. A dietitian will counsel both groups to reduce their salt intake to ~ 50mmol/day for 6 weeks. After 3 weeks participants will be asked to take enteric coated sodium chloride tablets (Slow-Sodium) providing 100mmol/day sodium for 3 weeks.
Intervention code [1] 284507 0
Lifestyle
Comparator / control treatment
The comparator group is the group that has neither of the polymorphisms undergoping the same intervention.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 286778 0
Blood pressure measured using an ambulatory blood pressure monitor over a 24hour period at each time point.
Timepoint [1] 286778 0
baseline, 3 weeks and 6 weeks
Primary outcome [2] 286786 0
plasma 20-HETE measured using gas chromatography mass spectrometry
Timepoint [2] 286786 0
baseline, 3 weeks and 6 weeks
Primary outcome [3] 286787 0
urinary 20-HETE measured using gas chromatography mass spectrometry
Timepoint [3] 286787 0
baseline, 3 weeks and 6 weeks
Secondary outcome [1] 296640 0
plasma and urinary isoprostanes measured using gas chromatography mass spectrometry
Timepoint [1] 296640 0
baseline, 3 weeks and 6 weeks

Eligibility
Key inclusion criteria
Healthy overweight men with waist circumference greater than or equal to 102cm and overweight healthy postmenopausal women with a waist circumference greater than or equal to 88cm who have a systolic BP greater or equal to 120mmHg. Volunteers who fit the criteria be screened for two genetic polymorphisms called CYP4F2 G1347A and CYP4A11 T8590C that affect 20-HETE levels. Two groups will be studied. A group that are carriers of the A allele of the CYP4F2 G1347A polymophism but who do not have the CYP4A11 T8590C polymorphism and a control group that have neither polymorphism will be studied
Minimum age
20 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
smoking, BMI>40, taking blood pressure or lipid lowering medication, drinking more than 3 standard drinks/day or 4 standard drinks in a single session, impaired renal function.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Volunteers are allocated according to their genotype. All suitable volunteers undergo the same intervention.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/08/2011
Actual
3/07/2011
Date of last participant enrolment
Anticipated
Actual
9/10/2012
Date of last data collection
Anticipated
Actual
Sample size
Target
40
Accrual to date
Final
53
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 284934 0
Government body
Name [1] 284934 0
National Health and Medical Research Council of Australia
Country [1] 284934 0
Australia
Primary sponsor type
Individual
Name
Professor Anne Barden
Address
School of Medicine & Pharmacology,
Royal Perth Hospital Unit, PO Box X2213, Perth, WA 6847
Country
Australia
Secondary sponsor category [1] 283806 0
Individual
Name [1] 283806 0
Professor Lawrie Beilin
Address [1] 283806 0
School of Medicine & Pharmacology,
Royal Perth Hospital Unit, PO Box X2213, Perth, WA 6847
Country [1] 283806 0
Australia
Other collaborator category [1] 260640 0
Individual
Name [1] 260640 0
Professor Ian Puddey
Address [1] 260640 0
School of Medicine & Pharmacology,
Royal Perth Hospital Unit, PO Box X2213, Perth, WA 6847
Country [1] 260640 0
Australia
Other collaborator category [2] 260641 0
Individual
Name [2] 260641 0
Professor Kevin Croft
Address [2] 260641 0
School of Medicine & Pharmacology,
Royal Perth Hospital Unit, PO Box X2213, Perth, WA 6847
Country [2] 260641 0
Australia
Other collaborator category [3] 260642 0
Individual
Name [3] 260642 0
Dr Natalie Ward
Address [3] 260642 0
School of Medicine & Pharmacology,
Royal Perth Hospital Unit, PO Box X2213, Perth, WA 6847
Country [3] 260642 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 286936 0
University of Western Australia Human Research Ethics committee
Ethics committee address [1] 286936 0
35 Stirling Hwy,
Crawley,
Western Australia, 6009
Ethics committee country [1] 286936 0
Australia
Date submitted for ethics approval [1] 286936 0
Approval date [1] 286936 0
18/12/2009
Ethics approval number [1] 286936 0
RA/4/1/2611

Summary
Brief summary
The effectiveness of treatment to reduce heart disease risk can vary a great deal between individuals. this is partly due to an individuals genetic makeup. Fatty acid metabolites called CYP450metabolites of arachidonic acid can act on blood vessels and the kidney to regulate blood pressure. one of these metabolites known as 20-HETE is known to be affected by dietary salt intake. we will study volunteers with two different genetic make-ups that affect 20-HETE levels differently to see if they affect blood pressure and heart disease risk. We will asses whether having either genetic make up causes a blood pressure and plasma and urinary 20-HETE when participants have different intakes of dietary salt.
Trial website
Trial related presentations / publications
Papers are being prepared for publication
Public notes

Contacts
Principal investigator
Name 33949 0
Prof Anne Barden
Address 33949 0
School of Medicine and Pharmacology Royal Perth Hospital Unit, GPO Box X2213 Perth, Western Australia, 6847.
Country 33949 0
Australia
Phone 33949 0
61892240272
Fax 33949 0
Email 33949 0
[email protected]
Contact person for public queries
Name 17196 0
Prof Anne Barden
Address 17196 0
School of Medicine and Pharmacology
Royal Perth Hospital Unit,
GPO Box X2213
Perth, Western Australia, 6847.
Country 17196 0
Australia
Phone 17196 0
61 8 92240272
Fax 17196 0
61 8 92240246
Email 17196 0
[email protected]
Contact person for scientific queries
Name 8124 0
Prof Anne Barden
Address 8124 0
School of Medicine and Pharmacology
Royal Perth Hospital Unit,
GPO Box X2213
Perth, Western Australia, 6847.
Country 8124 0
Australia
Phone 8124 0
61 8 92240272
Fax 8124 0
61 8 92240246
Email 8124 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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

Documents added automatically
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