ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12613000180718

Ethics application status

Approved

Date submitted

12/02/2013

Date registered

14/02/2013

Date last updated

14/02/2013

Type of registration

Prospectively registered

Titles & IDs

Public title

The effect of olive leaf extract on blood pressure in overweight prehypertensives

Scientific title

The effect of olive leaf extract on blood pressure in overweight prehypertensives

Secondary ID [1]

Nil known

Universal Trial Number (UTN)

U1111-1139-4371

Trial acronym

OLE study

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Hypertension

Condition category

Condition code

Cardiovascular

Hypertension

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

Subjects will consume 20ml phenolic-rich olive leaf extract liquid (OLE) at home daily for six weeks. There will be a four week wash out period between treatments.

Intervention code [1]

Prevention

Intervention code [2]

Treatment: Other

Comparator / control treatment

Control will be a polyphenol free placebo liquid, 20ml of which will be consumed daily for 6 weeks.

Control group

Placebo

Outcomes

Primary outcome [1]

Blood pressure measured via 24 hour ambulatory blood pressure monitors

Timepoint [1]

6 weeks

Secondary outcome [1]

Vascular function assessed by pulse wave velocity (PWV)

Timepoint [1]

6 weeks

Secondary outcome [2]

Lipid profile measured via serum assay

Timepoint [2]

6 weeks

Secondary outcome [3]

Inflammatory cytokines measured via plasma assay

Timepoint [3]

6 weeks

Secondary outcome [4]

Fructosamine measured via plasma assay

Timepoint [4]

6 weeks

Secondary outcome [5]

Glucose measured via plasma assay

Timepoint [5]

6 weeks

Secondary outcome [6]

Nitric oxide measured via plasma assay

Timepoint [6]

6 weeks

Secondary outcome [7]

Insulin measured via plasma assay

Timepoint [7]

6 weeks

Secondary outcome [8]

Haemostatic factors (D-dimer, PAI-1 ag, von Willebrand factor, prothrombin F1+2, factor VIII) measured via plasma assay

Timepoint [8]

6 weeks

Secondary outcome [9]

oxidised LDL measured via plasma assay

Timepoint [9]

6 weeks

Secondary outcome [10]

Obesity markers (adiponectin, CCL-2, complement factor D, CRP, IL-6, IL-10, leptin, resistin, serpin E1 and TNF-a) measured via plasma assay

Timepoint [10]

6 weeks

Eligibility

Key inclusion criteria

Inclusion criteria:
Men
18-65 years;
Non-smokers;
Prepared to consume olive leaf extract liquid
Systolic blood pressure 121-139 mmHg and diastolic blood pressure 81-89 mmHg
Body mass index (BMI) between 25-30 kg/m2 or waist >102 cm

Minimum age

18 Years

Maximum age

65 Years

Sex

Males

Can healthy volunteers participate?

Key exclusion criteria

Exclusion criteria:
Smokers
Using blood pressure, lipid lowering, thyroid disorder, blood clotting medication
Using supplements or functional foods that will affect lipid concentrations (e.g. sterol enriched spreads)
Chronic disease e.g. CHD, diabetes, cancer, digestive disorders
Individuals who are unwilling to refrain from consuming olive containing products for the duration of the study

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)

Subjects will be invited for a screening visit after completing a health and lifestyle questionnaire. If they fit the inclusion criteria they will be matched with another subject of a similar blood pressure and BMI and randomly assigned to a treatment. Products will be supplied in opaque bottles labelled with codes. Products will be bottled and labelled offsite so that the researcher and the subjects do not know which product is which.

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Randomization.com will be used to generate random block sizes.

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
The people analysing the results/data

Intervention assignment

Crossover

Other design features

Phase

Not Applicable

Type of endpoint/s

Efficacy

Statistical methods / analysis

SPSS will be used

Recruitment

Recruitment status

Not yet recruiting

Date of first participant enrolment

Anticipated

18/02/2013

Actual

Date of last participant enrolment

Anticipated

Actual

Date of last data collection

Anticipated

Actual

Sample size

Target

Accrual to date

Final

Recruitment outside Australia

Country [1]

New Zealand

State/province [1]

Auckland

Funding & Sponsors

Funding source category [1]

Commercial sector/Industry

Name [1]

Comvita

Address [1]

Comvita New Zealand Ltd
23 Wilson Road South
Paengaroa
Te Puke 3189
Bay of Plenty

Country [1]

New Zealand

Primary sponsor type

University

Name

Massey University, Institute of Food, Nutrition and Human Health

Address

Massey University, Institute of Food, Nutrition and Human Health

Albany Campus, Private Bag 102904, North Shore City, 0745, Auckland

New Zealand

Country

New Zealand

Secondary sponsor category [1]

University

Name [1]

Department of Food and Nutritional Sciences, University of Reading

Address [1]

PO Box 266
Whiteknight's Campus
University of Reading,
RG6 6AP
UK

Country [1]

United Kingdom

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

University of Reading Research Ethics Committee

Ethics committee address [1]

c/o Cat Ashford, Department of Pharmacy, PO Box 266, University of Reading, Whiteknight's Campus, Reading, Berkshire, RG6 6AP UK

Ethics committee country [1]

United Kingdom

Date submitted for ethics approval [1]

01/12/2012

Approval date [1]

Ethics approval number [1]

Summary

Brief summary

Cardiovascular disease (CVD) is the leading cause of death in New Zealand (40% of all deaths). 37% of New Zealanders suffer from high blood pressure (World Health Organisation 2008 figures), a well established modifiable risk factor for CVD. Above 115/75 mmHg, CVD risk doubles for each increment of 20/10 mmHg that blood pressure is raised. An increase in BMI and waist circumference has been associated with an increase in blood pressure. The leaves of the olive plant are rich in plant compounds known as polyphenols. This particular group of polyphenols are known secoiridoids, which are also present in olive oil and olives though at lower concentrations, are only found in this family of plants. Diets high in polyphenols have been found to reduce the risk of chronic diseases. Studies have shown that consumption of phenolic-rich olive leaf extract (OLE) can significantly reduce blood pressure in individuals suffering from high blood pressure (hypertension), with the magnitude of effect being comparable to a commonly used antihypertensive drug. In such trials OLE also resulted in an improved blood lipid (a reduction in total and LDL cholesterol and triacylglycerides) which also reduces CVD risk. One study testing the effect of OLE on individuals with mild or prehypertension (i.e. those with systolic blood pressure in the range 121–139 mmHg and diastolic blood pressure in the range 81-89 mmHg but not taking antihypertensive medication) also found these same improvements. OLE has been indicated to have the potential to improve other cardiovascular risk markers such as vascular function, inflammation, platelet aggregation, oxidation of LDL and glucose tolerance however much of this evidence is derived from animal, in vitro and ex vivo studies and so well designed and controlled human studies are required to verify that these findings are applicable to humans. Therefore OLE supplementation may be a useful dietary strategy for reducing CVD risk in a cohort of overweight prehypertensive individuals. 
The aim of the study is to determine the effect of OLE intake on blood pressure and other CVD risk markers in overweight subjects with mild hypertension and to link any study outcomes with the presence of OLE phenolics in urine

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

A/Prof Welma Stonehouse

Address

Massey University, Institute of Food, Nutrition and Human Health

Albany Campus, Private Bag 102904, North Shore City, 0745, Auckland

New Zealand

Country

New Zealand

Phone

+64 9 443 9755

Fax

w.stonehouse@massey.ac.nz

Contact person for public queries

Name

Stacey Lockyer

Address

Massey University, Institute of Food, Nutrition and Human Health

Albany Campus, Private Bag 102904, North Shore City, 0745, Auckland

New Zealand

Country

New Zealand

Phone

+64221762729

Fax

s.lockyer@pgr.reading.ac.uk

Contact person for scientific queries

Name

Stacey Lockyer

Address

Massey University, Institute of Food, Nutrition and Human Health

Albany Campus, Private Bag 102904, North Shore City, 0745, Auckland

New Zealand

Country

New Zealand

Phone

+64221762729

Fax

s.lockyer@pgr.reading.ac.uk

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

Source	Title	Year of Publication	DOI
Embase	Impact of phenolic-rich olive leaf extract on blood pressure, plasma lipids and inflammatory markers: a randomised controlled trial.	2017	https://dx.doi.org/10.1007/s00394-016-1188-y

N.B. These documents automatically identified may not have been verified by the study sponsor.

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Documents added manually

Documents added automatically