Is olive leaf extract useful to treat mild hypertension?

ISRCTN ISRCTN12535644
DOI https://doi.org/10.1186/ISRCTN12535644
ClinicalTrials.gov number NCT12535644
Secondary identifying numbers P17/038
Submission date
20/06/2018
Registration date
16/07/2018
Last edited
04/01/2024
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Circulatory System
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English Summary

Background and study aims
The most prevalent disease in adults is hypertension (high blood pressure). The guidelines propose to start treatment in primary care with healthy lifestyle advice and medication if blood pressure is not normalized or the patient has a high cardiovascular (heart disease) risk. The olive leaf contains oleuropein, which has traditionally been used to lower blood pressure. The aim of this study is to measure blood pressure in adults with hypertension treated with olive leaf extract.

Who can participate?
Patients aged 25-65 with hypertension

What does the study involve?
Participants are randomly allocated to take either two placebo (dummy) tablets once daily or two tablets of olive leaf extract once daily for 30 days, followed by a 15-day break, after which they take the other tablets for 30 days. Blood pressure is measured before and after each treatment period. A blood sample is taken before the first treatment period, during the 15-day break, and after the second treatment period. Each participant is asked on a weekly basis about the palatability of the tablets.

What are the possible benefits and risks of participating?
No direct benefits are expected for the participants. It is possible that the blood pressure measurement provides useful information for the subsequent treatment of these patients. Some cases of mild digestive intolerance and bitter taste have been reported with olive leaf extract. There is no serious risk to health.

Where is the study run from?
CAP Ernest lluch (Spain)

When is the study starting and how long is it expected to run for?
February 2017 to November 2018

Who is funding the study?
METHARISC Group

Who is the main contact?
1. Prof. Gabriel Coll de Tuero
gcolld@comg.cat
2. Ms Rufina Espín Sanchez
st525357@gmail.com

Contact information

Prof Gabriel Coll de Tuero
Scientific

Maluquer Salvador,11
Girona
17002
Spain

ORCiD logoORCID ID 0000-0001-7578-9569
Phone +34 (0)972421498
Email gcolld@comg.cat
Ms Rufina Espín Sanchez
Scientific

Canigó,9
Vilamalla
17469
Spain

ORCiD logoORCID ID 0000-0002-8873-3465
Phone +34 (0)677871273
Email st525357@gmail.com

Study information

Study designRandomized cross over double-blind trial
Primary study designInterventional
Secondary study designRandomised cross over trial
Study setting(s)GP practice, Workplace
Study typeTreatment, Efficacy
Participant information sheet Not available in web format, please use contact details to request a participant information sheet
Scientific titleMild hypertension treated with olive leaf extract clinical trial
Study hypothesis1. The treatment of mild essential hypertension (HT) with a brief advice on healthy lifestyle and leaf olive extract at doses recommended by the European Medicines Agency (EMA) will reduce the systolic and diastolic blood pressure significantly.
2. The treatment of the Mild HT with a brief advice on lifestyle modifications and olive leaf extract will allow a better control of blood pressure in a higher percentage than the group that receives only brief advice about lifestyle modifications.
Ethics approval(s)

Approved 10/10/2017, Comitè Ètic d´Investigació Clínica IDIAP (Gran Via Corts Catalanes, 587, Barcelona, 08007, Spain; +34 93 482 41 24; idiap@idiapjgol.org), ref: Protocol P17/038

ConditionHypertension
InterventionFrom the population of Figueres city a sample population of 48 individuals will be extracted, by simple random sampling, these will be randomized into two groups A and B:

A. OLE, marketed under the name Olive Oil extract 20% (oleuropein Sura Vitasan 60 capsules, containing 1000 mg extract and 20% oraloleic)
B. Placebo with the same appearance

Each of the participants will receive 2 placebo tablets each day (once daily) or 2 tablets of active principle each day (once daily) of olive leaf extract with 20% oleuropein (1000 mg). Each participant will take the active treatment or placebo for 30 days, followed by a 15-day washout period, after which they will take placebo or active treatment. Each participant will be randomized to start the first period with placebo or active treatment.

A blood sample analysis will be done before the 1st exposure, during the washout period (intermediate), and after the 2nd exposure has finished. Each participant will be asked on a weekly basis for their palatability.
Intervention typeSupplement
Primary outcome measureAmbulatory blood pressure (in mmHg) measured at the beginning and end of each treatment period (placebo or active treatment)
Secondary outcome measuresHypertension control (BP < 140/90 mmHg; in percentage) measured at the beginning and end of each treatment period (placebo or active treatment)
Overall study start date10/02/2017
Overall study end date31/10/2019

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit25 Years
Upper age limit65 Years
SexBoth
Target number of participants24 participants
Total final enrolment24
Participant inclusion criteria1. Men and women aged 25-65
2. Diagnosed with essential hypertension grade 1
3. Without allergy to the components of the leaf extract of the olive or the capsule
4. Low CV risk
5. Who don't take hypertension treatment a month before inclusion
6. Do not have a target organ lesion and/or chronic illnesses (kidney, respiratory, cardiac, liver, haematological, infectious, etc) according to the European Guide for the management of the HTA ESH ESC 2013
7. Informed consent
Participant exclusion criteria1. People with HTA grade 2 and 3
2. Grade 1 with a moderate CV risk, or high or very high according to the ESH-ESC 2013 Guidelines
3. With LOD or with subclinical vascular disease
4. With cognitive or idiomatic difficulty in fulfilling the instructions
5. Having chronic illnesses
6. Taking treatments that interfere or contraindicate the administration of the components of the olive leaf
7. Lactose intolerance
8. Pregnancy or breastfeeding
Recruitment start date15/06/2018
Recruitment end date30/12/2019

Locations

Countries of recruitment

  • Spain

Study participating centre

CAP Ernest lluch
Tramuntana, 2
Figueres
17600
Spain

Sponsor information

Institut Universitari d'Investigació en Atenció primària Jordi Gol i Gorina (IdIAP)
Research organisation

Gran Via de les Corts Catalanes,591 Atic
Barcelona
08007
Spain

Phone +34 (0)934824124
Email idiap@idiapjgol.org
ROR logo "ROR" https://ror.org/0370bpp07

Funders

Funder type

Other

METHARISC Group

No information available

Results and Publications

Intention to publish date30/09/2023
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planThe results of the trial will be published in international journals in the second quarter of 2019. The results will also be presented at national (Spanish Society of hypertension) and International (European Society of Hypertension) congresses.
IPD sharing planThe datasets generated during and/or analysed during the current study will be available upon request from Rufina Espín (st525357@gmail.com) from January 2019. The data will always be provided anonymized for reviews or meta-analysis whenever the principal investigators consider it appropriate. There are no legal restrictions to share this data as long as they are properly anonymized.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Other unpublished results 04/01/2024 No No
Thesis results 04/01/2024 No No

Additional files

ISRCTN12535644 Abstract (unpublished).pdf
ISRCTN12535644 Thesis.pdf

Editorial Notes

04/01/2024: The following changes were made to the trial record:
1. A thesis and unpublished abstract was uploaded as additional files
2. The ClinicalTrials.gov number was added.
3. The study setting 'Workplace' was added.
4. The total final enrolment was changed from 22 to 24.
26/09/2022: The intention to publish date was changed from 30/09/2020 to 30/09/2023.
20/11/2020: The following changes were made to the trial record:
1. The target number of participants was changed from 48 to 24.
2. The recruitment end date was changed from 30/09/2019 to 30/12/2019.
3. The trial participating centre address was added.
30/09/2019: The total final enrolment was added.
10/06/2019: The following changes were made:
1. The recruitment end date was changed from 30/05/2019 to 30/09/2019.
2. The overall trial end date was changed from 30/09/2019 to 31/10/2019.
12/03/2019: The following changes were made to the trial record:
1. The recruitment end date was changed from 28/02/2019 to 30/05/2019
2. The overall end date was changed from 30/06/2019 to 30/09/2019
3. The intention to publish date was changed from 28/02/2020 to 30/09/2020
24/10/2018: The following changes have been made:
1. The recruitment end date has been changed from 15/09/2018 to 28/02/2019.
2. The overall trial end date has been changed from 15/11/2018 to 30/06/2019.
3. The intention to publish date has been changed from 30/06/2019 to 30/02/2020.