The Effects of Types of Fruits and Vegetables on Vascular Function

Blood Pressure Clinical Trial

— CIRCUS  

Official title:

The Effects of Types of Fruits and Vegetables on Vascular Function in Prehypertensive Participants: a Pilot Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03410342
• Other study ID #: 17HH3878
• Secondary ID: Research Ethics
• Status: Completed
• Phase: N/A
• Start date: September 4, 2017
• Est. completion date: June 21, 2021

Study information

• Verified date: March 2022
• Source: University of Cambridge
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The CIRCUS study is a randomised controlled, cross-over trial to evaluate the effects of increased intakes of citrus fruits and cruciferous vegetables on vascular function in 36 untreated, prehypertensive participants.

Description:

The study comprises three 14-day dietary intervention periods, preceded by one week run-in period and separated by one week wash-out periods, 9 weeks in total. The diet will be fully controlled and provided by the researchers. Participants will receive in random order three interventions:

• 1 portion of fruits plus 1 portion of vegetables, of commonly consumed types per day. Intakes are at 25th percentile of UK consumption and will exclude citrus fruits, cruciferous and allium vegetables.

• 4 portions of fruits plus 4 portions of vegetables, of commonly consumed types per day excluding citrus fruits, cruciferous and allium vegetables.

• 4 portions of citrus fruits plus 4 portions of cruciferous vegetables per day.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 36
• Est. completion date: June 21, 2021
• Est. primary completion date: June 21, 2021
• Accepts healthy volunteers: No
• Gender: All
• Age group: 40 Years to 65 Years

Eligibility

Inclusion Criteria:

• 40 - 65 years

• Average systolic blood pressure of 125-140 mmHg at 2 measurements separated by >30 minutes

• No use of antihypertensive medication

• No reported current or previous diabetes mellitus, (secondary) hypertension, or metabolic, cardiovascular, renal, liver, thyroid, gastrointestinal diseases

• Body Mass Index between 20 - 35 kg/m2

• Non-smoker

• Average fruit and vegetable consumption of <4 portions per day (UK average, 40-65 years), or willing to reduce habitual daily fruit and vegetable intake.

Exclusion Criteria:

• Any medication likely to interfere with energy metabolism, appetite regulation and hormonal balance.

• Excessive alcohol intake of > 21 units per week (females) or >28 units per week (male) and not willing to limit alcohol intake to maximum of 1 unit/day

• Physical activity of >=10 hours/week of moderate to vigorous physical activity

• Weight loss or gain of >=3 kg in the preceding 3 months

• Use of dietary supplements or unwilling to stop supplement use >= 2 weeks before enrolment and during intervention

• Pregnancy or lactation

• Intervention specific factors, including:

• Unable or unwilling to consume provided diets during the intervention

• Unsufficient storage space for provided diets

• Food sensitivities or vegetarian/vegan diet by choice

• Participation in another intervention study at the same time

• Living > 15 miles from the Imperial/NIHR Clinical Research Facility at Hammersmith Hospital

• No signed informed consent

Related Conditions & MeSH terms

• Blood Pressure
• Cardiovascular Risk Factor
• Vascular Stiffness

Intervention

Other:
• LFV
1 apple/banana/small bunch of grapes per day plus 1 portion of carrot/pepper/tomato per day
• HFV
4 portions of fruits (apples, bananas, grapes, pears) plus 4 portions of vegetables (carrots, cucumber, sweet peppers, tomatoes), of commonly consumed types per day excluding citrus fruits, cruciferous and allium vegetables.
• CC
4 portions of citrus fruits (clementines, grapefruits, lemons, oranges) plus 4 portions of cruciferous vegetables (broccoli, brussels sprouts, cauliflower, kale, savoy cabbage) per day.

Locations

Country	Name	City	State
United Kingdom	Cambridge Epidemiology & Trials Unit	Cambridge
United Kingdom	Imperial/NIHR Clinical Research Facility	London

Sponsors (2)

Lead Sponsor	Collaborator
University of Cambridge	Imperial College London

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Blood pressure	Changes in systolic and diastolic blood pressure (mmHg) measured by automated oscillometric device (average of 3 measurements).	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Arterial stiffness	Changes (end minus baseline values) in arterial stiffness (pulse wave analysis)	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Markers of cardiometabolic health measured in fasted blood samples	e.g. high-density lipoprotein	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Markers of endothelial function measured in fasted blood samples	e.g. C-Reactive Protein	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Markers of low-grade inflammation measured in fasted blood samples	e.g. Interleukin-6	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Urinary metabolic profiles	(Un)targeted metabolic profiling by NMR and MS	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Circulatory metabolic profiles	(Un)targeted metabolic profiling by NMR and MS	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Established objective markers of food intake	e.g. vitamin C	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Faecal microbiome composition	Measured by 16SrRNA gene sequencing	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Cognitive function	e.g. Stroop-test	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks
Secondary	Self-rated general health and mental well-being	e.g. Positive and Negative Affect Schedule (PANAS) that consists of two 10-item scales to measure both positive and negative affect. Each item is rated on a Likert scale of 1 (not at all) to 5 (very much). Positive and negative affect scores are added seperately to a reange from 10 to 50. Higher positive scores represents higher levels of positive affect. Lower negative scores respresaent lower levels of negative affect.	Measured on the morning after each of three recurring run-in periods and after each of three recurring 2-week intervention periods, 6 times total during 9 weeks