Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
N/A
Study information
Scientific title
Effects of virgin olive oil enriched with phenolic compounds on blood pressure and endothelial function: a randomised double-blind crossover controlled trial
Acronym
OLIPA study
Study hypothesis
Increased antioxidant capacity exerted by phenolic compounds improved endothelial function leading to reduced blood pressure in postprandial state.
Ethics approval
Local medical ethics committee (Comité d'Ètica d'Investigació Clínica Hospital Universitari Sant Joan, Reus) approved, 24/04/2008, ref: 08-04-24/4proj5
Study design
Randomised double-blind crossover controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Ischaemic reactive hyperaemia/blood pressure
Intervention
All participants will follow a stabilisation period of 1 week with a low saturated fat diet. The day before to the postprandial test was followed by a polyphenol-free diet. Participants will be randomised individually between two postprandial tests:
1. Virgin olive oil. This will have a polyphenol content of 332.63 mg/kg (or 332.63 ppm measured by HPLC-DAD), an amount similar to oils in the area.
2. Virgin olive oil enriched with polyphenols. This will be enriched with polyphenols from defatted olive paste, which increase the concentrations up to three times, reaching a total content of 1008.14 mg/kg (or 1008.14 ppm measured by HPLC-DAD). These oils are prepared by the research group from Universitat de Lleida.
Participants will be provided with 80 g of bread containing 30 ml of the oil they have been allocated to. For 300 minutes after ingestion, participants will rest and may only drink water. One week later, participants will take the other investigational product in the same manner as before.
Diet monitoring will be conducted through a 3-day dietary record, in weeks 1 and 2. Participants are advised to maintain their usual physical activity and are monitored by a physical activity questionnaire.
Intervention type
Drug
Phase
Not Applicable
Drug names
Virgin olive oil enriched with phenolic compounds
Primary outcome measure
1. Blood pressure, measured at baseline and 120, 240 and 300 minutes on each study day
2. Endothelial function and activation biomarkers, measured at baseline and 120 , 240 and 300 minutes on each study day
Secondary outcome measures
Difference between the two oils (from baseline to 120, 240 and 300 minutes) of the following parameters:
1. The concentration of phenolic compounds in plasma, up to 300 minutes
2. Lipoproteins (total cholesterol, low density lipoprotein [LDL] cholesterol, high density lipoprotein [HDL] cholesterol, triglycerides) and apolipoproteins A1 and B100
3. Liver function tests
4. Angiotensin converting enzymes (ACE) inhibitory activity
5. Biomarkers of oxidation (LDL oxidised lipoperoxides, 8-epi-prostaglandin F2)
6. Biomarkers of inflammation (interleukin 6, high sensitivity C-reactive protein [hsCRP])
7. Antithrombotic activity biomarkers (plasminogen activator inhibitor-1 [PAI-1], factor VII antigen [FVIIag], activated factor VII [FVIIa])
8. Endothelial activation biomarkers (vascular cell adhesion molecules [VCAMs], intercellular adhesion molecules [ICAMs], e-selectin)
9. The relationship between nitrate (NO3)/nitrite (NO2)
10. Glycaemia and insulin resistance by Homeostatic Model Assessment (HOMA) index
11. The genetic profile of genes involved in endothelial function and blood pressure
Overall trial start date
28/01/2009
Overall trial end date
31/03/2010
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Healthy volunteers aged 18 to 75 years, either sex
2. Systolic blood pressure levels upper or equal 120 to 159 mmHg and/or diastolic blood pressure upper or equal 80 to 99 mmHg without antihypertensive treatment
Participant type
Healthy volunteer
Age group
Adult
Gender
Both
Target number of participants
30 (15 men and 15 women)
Participant exclusion criteria
1. Low density lipoprotein cholesterol (LDL-c) levels upper 189 mg/dL
2. Triglycerides upper 350 mg/dL (the threshold level to determine LDL-c by the Friedewald formula)
3. Chronic alcoholism
4. Body mass index (BMI) upper 30 kg/m^2
5. Statin treatment prior to initiating the trial and would not have left at least 2 months before starting the study
6. Antihypertensive treatment prior to initiating the trial and would not have left at least 2 months before starting the study
7. Having diabetes mellitus (if you develop a blood glucose, fasting, upper 126 mg/dL, should be repeated and confirmed)
8. Renal disease (plasma creatinine levels upper 1.4 mg/dL for women and upper 1.5 mg/dL for men
9. Having acute infectious diseases, malignancies, severe liver insufficiency, chronic respiratory insufficiency or associated endocrine diseases
10. Other conditions such as special nutritional requirements or medications that may affect lipid metabolism or blood pressure
11. Participate or participating in a clinical trial in the last 3 months
12. Incapacity to continue in the study
13. History of gastrointestinal disease that can impair the absorption of nutrients
14. Suicide attempt
Recruitment start date
28/01/2009
Recruitment end date
31/03/2010
Locations
Countries of recruitment
Spain
Trial participating centre
C/ Sant Llorenç, 21
Reus
43201
Spain
Sponsor information
Organisation
Rovira i Virgili University (Spain)
Sponsor details
Health Science Faculty
C/ Sant Llorenç
21
Reus
43201
Spain
Sponsor type
University/education
Website
Funders
Funder type
Government
Funder name
Spanish Ministry of Education and Science (Spain) (ref: AGL2005-07881-C02-01/ALI)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
Publication list
2015 results in: http://www.ncbi.nlm.nih.gov/pubmed/25148955
Publication citations
-
Results
Valls RM, Farràs M, Suárez M, Fernández-Castillejo S, Fitó M, Konstantinidou V, Fuentes F, López-Miranda J, Giralt M, Covas MI, Motilva MJ, Solà R, Effects of functional olive oil enriched with its own phenolic compounds on endothelial function in hypertensive patients. A randomised controlled trial., Food Chem, 2015, 167, 30-35, doi: 10.1016/j.foodchem.2014.06.107.