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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/ct2/show/NCT01796561




Registration number
NCT01796561
Ethics application status
Date submitted
20/02/2013
Date registered
21/02/2013
Date last updated
11/10/2013

Titles & IDs
Public title
The Effect of Olive Leaf Extract on Blood Pressure in Overweight Prehypertensives
Scientific title
Effect of Chronic Polyphenol-rich Olive Leaf Extract Intake on Cardiovascular Risk Markers
Secondary ID [1] 0 0
OLE chronic study
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypertension 0 0
Condition category
Condition code
Cardiovascular 0 0 0 0
Hypertension

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - Olive leaf extract liquid

Active Comparator: Olive leaf extract liquid - 20ml of polyphenol-rich olive leaf extract liquid to be consumed daily for 6 weeks

Placebo Comparator: Placebo liquid - 20ml of polyphenol-free placebo liquid (containing water, glycerin, flavours, colours and aromas) to be consumed daily for 6 weeks


Other interventions: Olive leaf extract liquid
Commercially available polyphenol-rich olive leaf extract liquid
Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Blood pressure measured via 24 hour ambulatory blood pressure monitors
Timepoint [1] 0 0
6 weeks
Secondary outcome [1] 0 0
Vascular function assessed by pulse wave velocity (PWV)
Timepoint [1] 0 0
6 weeks
Secondary outcome [2] 0 0
Lipid profile measured via serum assay
Timepoint [2] 0 0
6 weeks
Secondary outcome [3] 0 0
Inflammatory cytokines measured via plasma assay
Timepoint [3] 0 0
6 weeks
Secondary outcome [4] 0 0
Fructosamine measured via plasma assay
Timepoint [4] 0 0
6 weeks
Secondary outcome [5] 0 0
Glucose measured via plasma assay
Timepoint [5] 0 0
6 weeks
Secondary outcome [6] 0 0
Nitric oxide measured via plasma assay
Timepoint [6] 0 0
6 weeks
Secondary outcome [7] 0 0
Insulin measured via plasma assay
Timepoint [7] 0 0
6 weeks
Secondary outcome [8] 0 0
Haemostatic factors (D-dimer, PAI-1 ag, von Willebrand factor, prothrombin F1+2, factor VIII) measured via plasma assay
Timepoint [8] 0 0
6 weeks
Secondary outcome [9] 0 0
Oxidised LDL measured via plasma assay
Timepoint [9] 0 0
6 weeks
Secondary outcome [10] 0 0
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] 0 0
6 weeks

Eligibility
Key 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?
Yes
Key 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)
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 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
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
1/02/2013
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
1/10/2013
Sample size
Target
Accrual to date
Final
60
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 0 0
New Zealand
State/province [1] 0 0
Auckland

Funding & Sponsors
Primary sponsor type
Other
Name
University of Reading
Address
Country
Other collaborator category [1] 0 0
Other
Name [1] 0 0
Massey University
Address [1] 0 0
Country [1] 0 0

Ethics approval
Ethics application status

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
https://clinicaltrials.gov/ct2/show/NCT01796561
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Welma Stonehouse, PhD
Address 0 0
Massey University
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/ct2/show/NCT01796561