Diet and Vascular Health Study (BROCCOLI)

The aim of this study is to examine the effects of a diet rich in broccoli on cardiovascular disease risk using biochemical indicators such as blood lipid profiles, most notably cholesterol; markers of inflammation as well as established physiological measurements such as Pulse wave velocity (PWV), Augmentation index (AIx) and Ambulatory Blood Pressure Measurements (ABPM). Broccoli contains compounds known as glucosinolates which are metabolised to isothiocyanates when consumed. The major glucosinolate in broccoli is known as glucoraphanin which produces the isothiocyanate sulforaphane. The glucosinolates are thought to be the principal component in broccoli that may reduce CVD risk. The investigators will use a standard cultivar of broccoli and a cultivar that has enhanced levels of glucosinolates ('HG broccoli'). This broccoli has been used in previous intervention studies (e.g. ClinicalTrials.gov NCT00535977). Volunteers will be asked to consume 400g of standard broccoli, HG broccoli or peas each week over a 12 week period in a double blinded (for the broccoli) parallel study. The volunteers recruited will, according to the Joint British Societies (JBS 2) Guidelines on the prevention of cardiovascular disease (CVD) in clinical practise, have a 10-20% (mild to moderate) risk of developing cardiovascular disease or having a cardiovascular (CV) event in the next 10 years.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Disease
• Intervention / Treatment: Dietary supplement: Diet and Vascular Health; Dietary supplement: Diet and Vascular Health Study

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Norfolk
    • Norwich, Norfolk, United Kingdom, NR4 7UA
      • Institute of Food Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Men and women aged ≥ 50 years will be recruited onto the study using the JBS 2 cardiac risk assessor calculator (Copyright University of Manchester 1998): Scores of 10-20% will be acceptable for participation in the study.
• Total cholesterol ≥ 5.0mmol/L

• Blood pressure measurements

  • Systolic≥ 120mmHg
  • Diastolic ≥ 80mmHg
  • BMI ≥20
  • Smokers and Non Smokers

Exclusion Criteria:

• Diagnosed diabetics;
• Fasting glucose >6mmol/L;
• Blood pressure <90/50 or 95/55 if symptomatic; >160/100
• Chronic kidney disease;
• Those on any lipid lowering therapies like statins, bile acid sequestrants, cholesterol absorption inhibitors and nicotinic acid;
• Those who have suffered a cardiovascular event like stroke, myocardial infarction or trans ischemic attacks;
• Peripheral vascular disease including Claudication
• Consumption of fish oil supplements (unless volunteer is willing to discontinue their use 4 weeks prior to the start of the)
• Parallel participation in another research project which involves dietary intervention and/or sampling of biological fluids/materials
• Any person related or living with any member of the study team
• Participation in another research project which involves blood sampling within the last four months; Blood from both studies should not exceed 470mL
• BMI <20
• BMI >40
• Fasting total cholesterol > 8.0mmol/L
• Gastrointestinal disease (excluding hiatus hernia) unless symptomatic or study intervention/procedure is contraindicated
• Going on holiday for more than 7 days in any single period or within 2 weeks of their clinical appointment at the CRTU
• Currently suffering from or have suffered from any neck and throat injuries and surgery

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Standard Broccoli	Dietary supplement: Diet and Vascular Health; One group will consume 400g of standard broccoli each week for 12weeks; the second group will consume 400g of the high glucosinolate broccoli each week for 12weeks while the third group will consume 400g of peas each week for 12weeks. The broccoli and the peas will be consumed on top of the volunteer's standard diet.
Experimental: High Glucosinolate Broccoli	Dietary supplement: Diet and Vascular Health; One group will consume 400g of standard broccoli each week for 12weeks; the second group will consume 400g of the high glucosinolate broccoli each week for 12weeks while the third group will consume 400g of peas each week for 12weeks. The broccoli and the peas will be consumed on top of the volunteer's standard diet.
Experimental: Peas	Dietary supplement: Diet and Vascular Health Study; One group will consume 400g of standard broccoli each week for 12weeks; the second group will consume 400g of the high glucosinolate broccoli each week for 12weeks while the third group will consume 400g of peas each week for 12weeks. The broccoli and the peas will be consumed on top of the volunteer's standard diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Examination of the indicators of CVD after the consumption of broccoli, high glucosinolate broccoli and peas.	To examine the effects of a diet rich in broccoli on the systemic indicators of CVD including total cholesterol as well as established physiological measurements such as ambulatory blood pressure (BP), Augmentation Index (AIx) and Pulse Wave velocity (PWV) in subjects with a mild to moderate (10-20%) risk of developing CVD within the next 10 years	Week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The determination of key polymorphic genes of the trial subjects	To determine the genotype of individuals for key polymorphic genes (GSTM1, GSTT1 and GSTP1) and relate them to observed changes in CVD risk.	Baseline

Collaborators and Investigators

• Sponsor: Quadram Institute Bioscience
• Collaborators: University of East Anglia; Clinical Research and Trials Unit (Norfolk & Norwich University Hospital, UK)

Publications and helpful links

General Publications

• Armah CN, Traka MH, Dainty JR, Defernez M, Janssens A, Leung W, Doleman JF, Potter JF, Mithen RF. A diet rich in high-glucoraphanin broccoli interacts with genotype to reduce discordance in plasma metabolite profiles by modulating mitochondrial function. Am J Clin Nutr. 2013 Sep;98(3):712-22. doi: 10.3945/ajcn.113.065235.

Study record dates

Study Major Dates

• Study Start: January 1, 2010
• Primary Completion (Actual): December 1, 2013
• Study Completion (Actual): December 1, 2013

Study Registration Dates

• First Submitted: April 27, 2010
• First Submitted That Met QC Criteria: April 30, 2010
• First Posted (Estimate): May 3, 2010

Study Record Updates

• Last Update Posted (Estimate): July 29, 2014
• Last Update Submitted That Met QC Criteria: July 28, 2014
• Last Verified: July 1, 2014

More Information

Terms related to this study

• Keywords: Cholesterol; Cardiovascular Disease; Arterial Stiffness; Ambulatory blood pressure; Cardiovascular Disease risk (mild to moderate)
• Additional Relevant MeSH Terms: Cardiovascular Diseases
• Other Study ID Numbers: 2009IFR01