Magnetic Resonance Imaging-Portfolio Diet Study #7
- Conditions
- HypercholesterolemiaCardiovascular DiseasesMetabolic SyndromeDiabetesObesity
- Interventions
- Behavioral: Portfolio Plus DietBehavioral: DASH-like (high fibre) dietary advice
- Registration Number
- NCT02078635
- Lead Sponsor
- Unity Health Toronto
- Brief Summary
Presently in Canada, 29% of deaths are due to cardiovascular disease (CVD), costing $20.9 billion annually. The investigators have, therefore, brought together an unique network of investigators at different stages in their careers with a range of disciplines (nutrition, cardiology, diabetes, imaging, physics, clinical trials, statistics, laboratory medicine, primary care, genetics, psychology, knowledge translation (KT), and epidemiology) and with international recognition , experience and connections, to undertake a multi-centre study which will test the ability of the dietary Portfolio PLUS approach over 3 years to reduce the progression of plaque build-up in the carotid artery as assessed by Magnetic Resonance Imaging (MRI) in individuals with hypercholesterolemia.
The dietary portfolio of cholesterol-lowering foods (viscous fibres, soy protein, plant sterol and nuts) which has been proven in many of their studies to be an effective cholesterol-lowering diet will be further enhanced by increased levels of monounsaturated fats (MUFA) and low glycemic index foods. Will this enhanced dietary strategy (dietary Portfolio PLUS ) reduce the progression of carotid atheromatous lesions, LDL-C and blood pressure while reducing the number of hyperlipidemic individuals requiring statins?
- Detailed Description
As Western populations age and as body weight increases, the need for dietary strategies to reduce Coronary Heart Disease (CHD) risk continues. The investigators are now in a position to put together a dietary approach which will be a significant advance over current dietary advice for CHD risk reduction. The investigators believe this study using imaging and functional techniques is now needed to 1) demonstrate an improvement in estimated CHD risk based on anatomical changes rather than serum risk factors. 2) encourage popular uptake and clinical use of this combination dietary strategy and 3) stimulate a larger longer term trial with CHD events.
Participants for this study will be recruited in 4 academic centres across Canada (Quebec, Toronto, Winnipeg and Vancouver). They will be in the low or moderate risk category based on the current Canadian Cardiovascular Society's (CCS) Guidelines 2012 and would normally be considered for initial treatment with lifestyle only. All participants will first be screened by ultrasound for the presence of plaque in the carotid arteries and will then be randomized to one of the 2 treatment arms: Portfolio Plus diet (test) or modified DASH diet (control), both given as routine clinical advice with follow up visits at 3-month intervals for 6 months and then twice yearly for the remainder of the 3 year trial.
Prior to starting either diet, participants will undergo screening ultrasound examination of both right and left carotids to enable selection of those individuals whose intima-media thickness would be 5-30% below the cut point considered by the Mannheim Consensus as relevant arterial thickening to ensure a relatively low risk group, yet with some measurable arterial thickening. The main outcome will be MRI assessment of maximum vessel wall volume. This assessment will be repeated at year 3. It will be emphasized at the outset that both the dietary portfolio and the DASH-like diets have been associated with benefits in terms of cholesterol reduction to provide equal encouragement for those randomized to the test and control groups. Portfolio and DASH-like dietary advice will consist of half hour individual sessions with the dietitian at baseline, 3, and 6 months and then at 6-month intervals. Prior to starting each diet, instruction will be given on achieving the dietary goals.
At follow-up visits, the participants' completed 7-day diet records will be discussed and the original advice reinforced. Every effort will be made to obtain study blood samples and carotid imaging data from all subjects at the designated times regardless of adherence to the dietary aspects of the study protocol. All subjects will be included in the intention-to-treat analysis.
Recruitment & Eligibility
- Status
- WITHDRAWN
- Sex
- All
- Target Recruitment
- Not specified
Eligible participants will be:
- Adult males that are within 30% of their target LDL-cholesterol for the low or moderate risk category according to the 2012 Canadian Cardiovascular Society Guidelines.
- Postmenopausal women that are within 30% of their target LDL-cholesterol for the low or moderate risk category according to the 2012 Canadian Cardiovascular Society Guidelines.
Participants will have the following characteristics:
-
BMI 25-40 kg/m2 with body weight that has remained constant (within ±2kg) over the last 3 months preceding the onset of the study.
-
Measurable arterial thickening at screening (carotid intima-media thickness of >1.0mm)
-
Plus at least 1 of the following 3 criteria:
- are treated with statins
- are statin intolerant
- have refused statin treatment after consultation with the appropriate physician
Individuals with the following conditions will be excluded:
-
major cardiovascular event
- stroke or
- myocardial infarction
-
Cardiac conditions that compromise normal function
- mitral valve disease
- heart failure
- angina
-
familial hypercholesterolemia
-
secondary causes of hypercholesterolemia
- hypothyroidism (unless treated and on a stable dose of L-thyroxine)
- renal or liver disease
-
diabetes
-
serum triglycerides >4.5 mmol/L
-
uncontrolled blood pressure
-
major disability
-
disorders requiring continuous medical attention and treatment
- chronic heart failure
- liver disease
- renal failure
- cancer (except non-melanoma skin cancer--basal cell, squamous cell)
-
chronic infections (bacterial or viral)
-
chronic inflammatory diseases ( lupus, ulcerative colitis)
-
other autoimmune diseases (eg celiac disease or gluten sensitivity)
-
major surgery <6 months prior to randomization
-
conditions that make them unsuitable for MRI (e.g. have metal implants or are claustrophobic)
-
alcohol consumption >2 drinks/ day
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Portfolio Plus Diet Portfolio Plus Diet Participants will be advised to follow a low glycemic index dietary portfolio. Specifically, the advice will be to limit saturated fat (to \<7% of total calories and cholesterol to \<200 mg/d) plus inclusion of viscous fibres, soy protein, plant sterols and nuts, 5% extra monounsaturated fat and selection of low glycemic index foods; emphasizing current recommendations for fruit and vegetable intakes (5-10 servings/d) DASH-like (high fibre) diet DASH-like (high fibre) dietary advice The DASH-like dietary advice will emphasize a diet of whole grains, low-fat dairy and current recommendations for fruit and vegetables (5-10 servings/day)
- Primary Outcome Measures
Name Time Method Change from baseline of the maximum vessel wall volume of the carotid arteries At baseline and year 3 Assessed by MRI
- Secondary Outcome Measures
Name Time Method Intra-plaque lipid (lipid-rich necrotic core) baseline and year 3 Assessed by MRI
Intra-plaque hemorrhage (IPH) At baseline and year 3 Assessed by MRI
initiation of statin therapy baseline and year 3 According to current CCS guidelines
blood pressure and pulse rate At months 0, 3, 6, 12, 18, 24, 30, 36
Trial Locations
- Locations (4)
Risk Factor Modification Centre, St. Michael's Hospital
🇨🇦Toronto, Ontario, Canada
Institute of Nutraceuticals and Functional Foods and the Quebec Heart and Lung Institute, Laval University
🇨🇦Quebec City, Quebec, Canada
Healthy Heart Lipid Clinic, St. Paul's Hospital
🇨🇦Vancouver, British Columbia, Canada
Richardson Center for Functional Foods and Nutraceuticals and the St. Boniface Hospital Cardiovascular Center, University of Manitoba
🇨🇦Winnipeg, Manitoba, Canada