Canola Oil Multicentre Intervention Trial (COMIT)

This study has been completed.
Sponsor:
Collaborator:
University of Manitoba
Information provided by (Responsible Party):
Penny Kris-Etherton, Penn State University
ClinicalTrials.gov Identifier:
NCT01233778
First received: November 1, 2010
Last updated: March 14, 2013
Last verified: March 2013
  Purpose

The objectives of this study are to examine how the consumption of treatment oils (including canola oil, DHA enriched canola-oil, high oleic acid canola oil, flax oil, and safflower oil) influence endothelial function, inflammation, oxidation, body composition, and plasma lipoprotein characterization.


Condition Intervention
Cardiovascular Disease
Dietary Supplement: Canola Oil
Dietary Supplement: High Oleic Acid + DHA Canola Oil
Dietary Supplement: High Oleic Acid Canola Oil
Dietary Supplement: Flax Oil
Dietary Supplement: Safflower Oil

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver)
Primary Purpose: Prevention
Official Title: Canola and Flax Oils in Modulation of Vascular Function and Biomarkers of Cardiovascular Disease Risk

Resource links provided by NLM:


Further study details as provided by Penn State University:

Primary Outcome Measures:
  • Endothelial Health [ Time Frame: End of diet period 1 (week 4) ] [ Designated as safety issue: No ]
    Study subjects will undergo endothelial health assessment by EndoPAT analysis. The EndoPat procedure will occur while the subject is lying down in a relaxed state. Throughout the study, the inflation pressure of the EndoPAT device will be electronically set to 10mm Hg below diastolic BP. Testing begins with 10 min of rest. Following rest, baseline pulse amplitude is measured from each fingertip for 5 min. Next, arterial flow is interrupted for 5 min by a cuff placed on the forearm at an occlusion pressure of 250 mmHg. Following occlusion release, pulse amplitude recording continues for 5 min.

  • Endothelial Health [ Time Frame: End of diet period 2 (week 12) ] [ Designated as safety issue: No ]
    Study subjects will undergo endothelial health assessment by EndoPAT analysis. The EndoPat procedure will occur while the subject is lying down in a relaxed state. Throughout the study, the inflation pressure of the EndoPAT device will be electronically set to 10mm Hg below diastolic BP. Testing begins with 10 min of rest. Following rest, baseline pulse amplitude is measured from each fingertip for 5 min. Next, arterial flow is interrupted for 5 min by a cuff placed on the forearm at an occlusion pressure of 250 mmHg. Following occlusion release, pulse amplitude recording continues for 5 min.

  • Endothelial Health [ Time Frame: End of diet period 3 (week 20) ] [ Designated as safety issue: No ]
    Study subjects will undergo endothelial health assessment by EndoPAT analysis. The EndoPat procedure will occur while the subject is lying down in a relaxed state. Throughout the study, the inflation pressure of the EndoPAT device will be electronically set to 10mm Hg below diastolic BP. Testing begins with 10 min of rest. Following rest, baseline pulse amplitude is measured from each fingertip for 5 min. Next, arterial flow is interrupted for 5 min by a cuff placed on the forearm at an occlusion pressure of 250 mmHg. Following occlusion release, pulse amplitude recording continues for 5 min.

  • Endothelial Health [ Time Frame: End of diet period 4 (week 28) ] [ Designated as safety issue: No ]
    Study subjects will undergo endothelial health assessment by EndoPAT analysis. The EndoPat procedure will occur while the subject is lying down in a relaxed state. Throughout the study, the inflation pressure of the EndoPAT device will be electronically set to 10mm Hg below diastolic BP. Testing begins with 10 min of rest. Following rest, baseline pulse amplitude is measured from each fingertip for 5 min. Next, arterial flow is interrupted for 5 min by a cuff placed on the forearm at an occlusion pressure of 250 mmHg. Following occlusion release, pulse amplitude recording continues for 5 min.

  • Endothelial Health [ Time Frame: End of diet period 5 (week 36) ] [ Designated as safety issue: No ]
    Study subjects will undergo endothelial health assessment by EndoPAT analysis. The EndoPat procedure will occur while the subject is lying down in a relaxed state. Throughout the study, the inflation pressure of the EndoPAT device will be electronically set to 10mm Hg below diastolic BP. Testing begins with 10 min of rest. Following rest, baseline pulse amplitude is measured from each fingertip for 5 min. Next, arterial flow is interrupted for 5 min by a cuff placed on the forearm at an occlusion pressure of 250 mmHg. Following occlusion release, pulse amplitude recording continues for 5 min.


Secondary Outcome Measures:
  • Body Composition [ Time Frame: Week 4, 12, 20, 28 and 36 - End of each diet period ] [ Designated as safety issue: No ]
    To assess regional changes in body fat deposition, subjects will undergo a dual energy X-ray absorptiometry (DXA) scan at baseline (beginning of study) and end of each intervention period. Waist circumference measurements also will be taken at this time to track how much fat is lost from the abdominal area of the body.

  • Production of long chain fatty acids [ Time Frame: Week 4, 12, 20, 28 and 36 - End of each diet period ] [ Designated as safety issue: No ]
    On the 29th day of each diet phase you will be asked to consume three tablespoons of tagged water (known as deuterium). The movement of these tagged materials will allow us to assess the quantity of long chain fatty acids (EPA and DHA) that your body is producing in response to your diet. All of the above tagged materials are non-radioactive, non-toxic, and do not pose any health risk to you. Another fasting blood sample will be obtained when you return the next morning.

  • Plasma Lipids [ Time Frame: Week 4, 12, 20, 28 and 36 - End of each diet period ] [ Designated as safety issue: No ]
    Twelve-hour fasting blood samples (30ml) will be collected on day 1, 2, 29 and 30 for analyses of plasma lipids. Blood samples obtained on day 1 and 2 will be used to measure baseline values for study endpoints, whereas blood samples obtained on the two last days will be used to measure final endpoint values.

  • Plasma Cytokines [ Time Frame: Week 4, 12, 20, 28 and 36 - End of each diet period ] [ Designated as safety issue: No ]
    Twelve-hour fasting blood samples (30ml) will be collected on day 1, 2, 29 and 30 for analyses of C-reactive protein and inflammatory cytokines. Blood samples obtained on day 1 and 2 will be used to measure baseline values for study endpoints, whereas blood samples obtained on the two last days will be used to measure final endpoint values.


Enrollment: 43
Study Start Date: October 2010
Study Completion Date: April 2012
Primary Completion Date: March 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Canola Oil Dietary Supplement: Canola Oil
60g Canola oil daily per 3000kcal diet provided in a supplemental shake
Experimental: High Oleic Acid Canola + DHA Dietary Supplement: High Oleic Acid + DHA Canola Oil
60g high oleic acid canola oil + DHA daily per 3000kcal provided in a supplemental shake
Experimental: High Oleic Canola Oil Dietary Supplement: High Oleic Acid Canola Oil
60g high oleic acid canola oil daily per 3000kcal provided in a supplemental shake
Experimental: Flax & Safflower Oil (60:40) Dietary Supplement: Flax Oil
36g flax oil + 24g safflower oil daily per 3000kcal provided in a supplemental shake
Experimental: Safflower & Corn Oil (75:25) Dietary Supplement: Safflower Oil
45g safflower oil + 15g corn oil daily per 3000kcal provided in a supplemental shake

Detailed Description:

The consequence of total fat consumption on circulating plasma lipids and the incidence of cardiovascular disease has long been a central theme in nutrition research. Less well known is the influence of specific fatty acids on vascular endothelial function and the oxidative and inflammatory responses characteristic of atherogenesis. Omega 3 ( ω-3) fatty acids, including plant derived alpha-linolenic acid (18:3n-3, ALA) and marine derived eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA) have been shown to effectively modulate multiple cardiovascular risk factors in epidemiological, animal model and human clinical investigations. ALA is most commonly consumed as a major component of dietary canola and flaxseed oils and has a recommended intake of 1.1 and 1.6 g/d for women and men, respectively. EPA and DHA are consumed as fatty fish or fish oil and algae supplements with current recommended intakes of 500 mg/d (combined EPA and DHA).

ALA is thought to improve cardiovascular health by modulating circulating lipid concentrations, altering membrane structure and function by enhancing the total ω-3 fatty acid content of cell membrane phospholipids, and reducing inflammatory reactions by blocking the formation of arachidonic acid derived eicosanoids. However, there are extensive knowledge gaps in our understanding of the molecular mechanisms and clinical efficacy of ω-3 fatty acids in human health and disease prevention. Therefore, the purpose of this study is to further examine these relationships.

Feeding protocol and study treatments:

The study will proceed as a double blind, randomized cross-over controlled feeding study. Each treatment phase will be 30 days in duration, separated by 4-week washout periods. Subjects will consume a fixed composition of a precisely controlled basal, weight-maintaining diet (35% energy from fat, 50% carbohydrate, and 15% protein) supplemented with 60g/d of the following treatment oils: 1) canola oil; 2) DHA enriched canola-oil; 3) high oleic acid canola oil; 4) flax/corn oil (40:60); or 5) safflower/corn oil (75:25). Study diets will be prepared in a metabolic kitchen facility at each clinical site. Three isocaloric meals will be prepared each day for every subject. A 7-day rotating menu cycle will be used. Subjects will consume at least 1 of 3 daily meals under supervision. The other meals will be prepared and packed for every subject to be taken out. The study control and intervention oils will be delivered in milkshakes provided twice daily. Subjects will be instructed to consume only the prepared meals and limit their intake of alcohol to 2 drinks/week and caffeinated calorie free beverages to 40oz (5 drinks) per day. Diets will be planned for every subject according to his/her energy requirements and will be nutritionally adequate.

  Eligibility

Ages Eligible for Study:   20 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Aged 20-65 years
  • BMI = 22-32 kg/m2

In addition, eligibility will be based on metabolic syndrome criteria where we define eligibility on the basis of subjects having elevated waist circumference + 1 or more of the remaining 5 criteria:

  • Elevated waist circumference - > 102 cm for men and >88 cm for women
  • Elevated triglycerides - ≥ 1.7 mmol/L ( ≥150mg/dl) ( no upper limit)
  • Reduced HDL - < 1 mmol/L (<40 mg/dl) for men and < 1.3 mmol/L (<50 mg/dl)for women
  • Fasting glucose - ≥ 100 mg/dl (no upper limit)
  • Elevated blood pressure - systolic ≥130 and/or diastolic ≥85 mm HG

    • Unmedicated participants - upper limit of Stage 1 Hypertension: systolic ≤ 159 and/or diastolic ≤ 99 mm HG and participants must be free of end stage/target organ disease symptoms
    • BP medicated participants: acceptable as long as individuals meet the specified blood pressure range of <140/90 mmHg, and have been stable for at least 6 months.

Exclusion Criteria:

  • Smokers**
  • History of thyroid disease, diabetes, kidney or liver disease, heart disease, or other chronic diseases
  • Heavy alcohol consumption (>14 drinks/week)
  • Chronic anti-inflammatory medication use
  • Lactation, pregnancy, or desire to become pregnant during the study
  • Taking lipid lowering medications (cholestyramine, colestipol, niacin, clofibrate, gemfibrozil probucol, HMG CoA reductase inhibitors) within the last three months
  • Not willing to refrain from blood/plasma donation during the study period
  • Gall bladder removal

    • For purposes of the this study non-smoking is defined as >6 months smoke-free; there is some evidence to show that smoking cessation increases HDL levels and 6 months is adequate time for this to stabilize, however this time span was chosen based on the decreased rate of relapse after 6 months.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01233778

Locations
United States, Pennsylvania
Penn State University
University Park, Pennsylvania, United States, 16802
Sponsors and Collaborators
Penn State University
University of Manitoba
Investigators
Principal Investigator: Penny M Kris-Etherton, PhD, RD Penn State University
  More Information

No publications provided

Responsible Party: Penny Kris-Etherton, RD, PhD, Penn State University
ClinicalTrials.gov Identifier: NCT01233778     History of Changes
Other Study ID Numbers: PKE COMIT
Study First Received: November 1, 2010
Last Updated: March 14, 2013
Health Authority: United States: Institutional Review Board
Canada: Research Ethics Board

Keywords provided by Penn State University:
Cardiovascular disease
Omega-3 fatty acids
Inflammation
Endothelial function
Canola oil

Additional relevant MeSH terms:
Cardiovascular Diseases

ClinicalTrials.gov processed this record on September 30, 2014