Effects of a Long Term Dietary Portfolio and of Sequential Removal of Food Components From the Diet

Not Applicable

Completed

• Conditions: Cardiovascular Diseases; Hypercholesterolemia; Hyperlipidemia
• Interventions: Dietary Supplement: Dietary portfolio of cholesterol-lowering foods

• Registration Number: NCT00438893
• Lead Sponsor: University of Toronto

Brief Summary

The purpose of this study is to evaluate the long term effectiveness of the dietary portfolio, consisting of viscous fibers, soy products, nuts and plant sterols, as well as the effects of removing single food components from the dietary portfolio on cholesterol reduction and other cardiovascular risk factors.

Detailed Description

We have shown in 1-month metabolic studies that a dietary portfolio, consisting of soy products, viscous fibers, almonds and plant sterols in the form of margarine, can lower cholesterol to the same extent as first generation statins (cholesterol-lowering drugs). However, the long-term effectiveness of the dietary portfolio is not known. Furthermore, it is not known to what extent each of the food components contribute to the cholesterol reductions observed. We wish to therefore evaluate the long term effects of the dietary portfolio as well as the effects of removing single food components from the dietary portfolio on cholesterol reduction and other cardiovascular risk factors. We believe the removal of single food components will result in a reduction of the cholesterol-lowering effect to a similar extent as predicted with the cholesterol reductions observed when the food component is consumed alone.

Method:

66 subjects will be recruited for a 6-month to 5 year long-term dietary portfolio study with the option for continuation (re-consenting) at the end of 6, 12 or 24 months. The active dietary components consist of viscous fibers (including oat bran), soy products (including soy milk), almonds and plant sterols (sterol-enriched margarine). Lipids, blood pressure, body weight, and routine biochemical and hematology analyses will be performed over the 5 year period, with lipids and blood pressure measured at 2 monthly intervals. 40-50 subjects on the long term dietary portfolio study, all of whom will have been on the diet for at least 1 year, will be asked to remove a specific food component from their regular dietary portfolio for a 10 week period. After the 10 week period, subjects will be asked return to the normal dietary portfolio with all food components consumed and continue on the long-term dietary portfolio.

Bloods will be taken at weeks 0, 6 and 10 of the food component removal period; and at 2-monthly intervals for 20 weeks prior to and after the 10 week period while on the long-term dietary portfolio with all food components.

Study Timeline

• Study Start: 2003-09-01
• Study First Submitted: 2007-02-20
• Study First Submitted QC: 2007-02-20
• Study First Posted: 2007-02-22
• Primary Completion: 2009-05
• Study Completion: 2009-05
• Status Verified: 2018-10
• Last Update Submitted: 2018-10-10
• Last Update Posted: 2018-10-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 66

Inclusion Criteria

• Healthy adult men and postmenopausal women currently enrolled in the long-term portfolio study
• Body mass index <32 kg/m2
• Constant body weight over last 6 months preceding the onset of the study
• Fasting LDL-cholesterol concentration >4.1 mmol/L at diagnosis

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Exclusion Criteria

• women of child-bearing potential
• major cardiovascular event (stroke or myocardial infarction)
• positive molecular diagnosis of familial hypercholesterolemia
• secondary causes of hypercholesterolemia (hypothyroidism, unless treated & on a stable dose of L-thyroxine, renal or liver disease)
• use of cholesterol-lowering medications
• serum triglycerides >4.5 mmol/L
• blood pressure > 145/90 mmHg
• diabetes and/or major disorders such as liver disease, renal failure or cancer
• major surgery <6 months prior to randomization
• alcohol consumption >2 drinks per day

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
A portfolio of cholesterol-lowering foods	Dietary portfolio of cholesterol-lowering foods	Dietary advice to consume a dietary portfolio of cholesterol-lowering foods

Primary Outcome Measures

Name	Time	Method
LDL cholesterol	At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years
C-reactive protein	At weeks 0, 12, 24, 34, 52; then every 6 months to a total of 5 years
Total cholesterol	At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years
Blood pressure	At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years

Secondary Outcome Measures

Name	Time	Method
Routine Biochemistry and hematology measurements	At week 0, 12, 24 and every 6 months to 5 years
Body Weight	At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years
Compliance to dietary portfolio components	At years, 1, 2, 3, 4 and 5
Apolipoprotein A1 and B	At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years
Lp(a)	At weeks 0, 24, 52; then every 6 months to a total of 5 years
24 hour urinary markers and electrolytes (optional)	At week 0 and end of years 1, 2, 3, 4 and 5
Oxidative stress markers	week 0 and every 6 months to 5 years

Trial Locations

Locations (1)

Clinical Nutrition & Risk Factor Modification Centre, St. Michael's Hospital Health Centre; 🇨🇦 Toronto, Ontario, Canada