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The Health Effects of Blueberry Anthocyanins in Metabolic Syndrome (the CIRCLES-study) (CIRCLES)

Primary Purpose

Insulin Resistance, Metabolic Syndrome X

Status
Completed
Phase
Not Applicable
Locations
International
Study Type
Interventional
Intervention
Full dose blueberry
Half dose blueberry
Control
Sponsored by
University of East Anglia
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional basic science trial for Insulin Resistance

Eligibility Criteria

50 Years - 74 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • Men and postmenopausal women (≥ 1 year since last menstruation)
  • 50 to 75 years old
  • BMI of ≥ 25 kg/m2
  • 3 characteristics of metabolic syndrome i.e: Waist circumference ≥ 102 cm for men, ≥ 88 cm for women; Triglycerides ≥ 1.7 mmol/L (or drug treatment for elevated triglycerides); HDL-cholesterol < 1.0 mmol/L for men, < 1.3 mmol/L for women (or drug treatment for low HDL-cholesterol); Blood pressure ≥ 130 mm Hg systolic and/or ≥ 85 mm Hg diastolic blood pressure; Fasting blood glucose ≥ 5.56 mmol/L
  • Successful biochemical, haematological and urinalysis assessment at screening

Exclusion Criteria:

  • Current smokers, or ex-smokers ceasing < 6 months ago
  • Existing or significant past medical history of vascular disease or medical conditions likely to affect the study measures
  • Fructose intolerance or known allergies to the intervention treatments
  • On therapeutic diets or having experienced substantial weight loss within 3 months of screening
  • Taking flavonoid containing supplements (and unwilling to cease intake during, and 1 month preceding the trial)
  • Planning on altering consumption of vitamin supplements / fish oil capsules during the course of the study.
  • Prescribed hypoglycaemic, vasodilators or HRT medication.
  • Unsatisfactory biochemical, haematological or urinary assessment at screening, or measures considered to be counter indicative for the study
  • < 3 characteristics of the metabolic syndrome.

NB: REC approved NoSA granted to include those on anti-hypertensives (29JUL2014)

Sites / Locations

  • Harvard School of Public Health
  • Addenbrooke's hospital
  • Norwich Medical School University of East Anglia
  • Norfolk and Norwich University Hospital

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm Type

Active Comparator

Active Comparator

Placebo Comparator

Arm Label

Full dose blueberry

Half dose blueberry

Control

Arm Description

26g of freeze dried blueberry powder; equivalent to 2 portions of fresh blueberries per day. Frequency: 26g per day. Total duration: 6-month.

26g of freeze dried powder; containing 13g of freeze dried blueberry powder and 13g of placebo comparator material; equivalent to 1 portion of fresh blueberries per day. Frequency: 26g per day. Total duration: 6-month.

Matched control powder; matched for appearance, taste and sugar content. Frequency: 26g per day. Total duration: 6-month.

Outcomes

Primary Outcome Measures

Insulin resistance
Assessed, in the fasted state, via HOMA-IR calculation in all participants; indirect assessment.

Secondary Outcome Measures

Insulin resistance
Assessed in a sub-group via hyperinsulinemic euglycaemic clamp.
Blood pressure and blood vessel regulation
Measurements taken of arterial stiffness, endothelial function and blood pressure.
Lung function
Assessed via standard spirometry techniques and biological assessment of exhaled samples.
Cognitive function
Assessed via a validated cognitive test battery.
Liver fat and blood flow assessment
Assessment via 3T MRI in a sub-group of participants.
Bio-availability
Flavonoid and metabolite levels will be assessed in blood and 24 hour urine samples.
Metabolite phenotype effects
The gut microbiome will be assessed from faecal sample collection and the impact on metabolism and of genotype, will be assessed via a targeted approach.
Acute +24 hour effect of single (26g) intervention intake, given with high fat challenge
Insulin resistance, lipaemia, vascular, cognitive and lung function measured pre- and post-intervention in combination with a high fat challenge in a sub-group of participants. Urine samples and blood samples (over a 24 hour period) will be taken for biomarker analysis.

Full Information

First Posted
January 10, 2014
Last Updated
September 28, 2017
Sponsor
University of East Anglia
Collaborators
Harvard School of Public Health (HSPH)
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1. Study Identification

Unique Protocol Identification Number
NCT02035592
Brief Title
The Health Effects of Blueberry Anthocyanins in Metabolic Syndrome (the CIRCLES-study)
Acronym
CIRCLES
Official Title
The Effects of Blueberry Anthocyanins on Insulin Resistance and Vascular, Lung and Cognitive Function in a Population With Metabolic Syndrome.
Study Type
Interventional

2. Study Status

Record Verification Date
January 2017
Overall Recruitment Status
Completed
Study Start Date
January 2014 (undefined)
Primary Completion Date
November 7, 2016 (Actual)
Study Completion Date
November 7, 2016 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
University of East Anglia
Collaborators
Harvard School of Public Health (HSPH)

4. Oversight

Data Monitoring Committee
No

5. Study Description

Brief Summary
The purpose of this study is to determine the dose-dependent impact of 6 month freeze-dried blueberry powder intake on insulin sensitivity and resistance, cardiovascular disease risk factors, and lung and cognitive function in overweight and obese participants with metabolic syndrome. We will also examine acute post-prandial effects of blueberry intake (at baseline and at 6-months).

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Insulin Resistance, Metabolic Syndrome X

7. Study Design

Primary Purpose
Basic Science
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
ParticipantCare ProviderInvestigatorOutcomes Assessor
Allocation
Randomized
Enrollment
144 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
Full dose blueberry
Arm Type
Active Comparator
Arm Description
26g of freeze dried blueberry powder; equivalent to 2 portions of fresh blueberries per day. Frequency: 26g per day. Total duration: 6-month.
Arm Title
Half dose blueberry
Arm Type
Active Comparator
Arm Description
26g of freeze dried powder; containing 13g of freeze dried blueberry powder and 13g of placebo comparator material; equivalent to 1 portion of fresh blueberries per day. Frequency: 26g per day. Total duration: 6-month.
Arm Title
Control
Arm Type
Placebo Comparator
Arm Description
Matched control powder; matched for appearance, taste and sugar content. Frequency: 26g per day. Total duration: 6-month.
Intervention Type
Other
Intervention Name(s)
Full dose blueberry
Intervention Description
Full dose: 26g of freeze dried blueberry powder to be incorporated into the habitual diet. Dietary restrictions will be observed (i.e. avoidance of blueberry, and restricted intake of anthocyanin rich foods) for 21 days prior to the first assessment visit and throughout the study.
Intervention Type
Other
Intervention Name(s)
Half dose blueberry
Intervention Description
Half dose: 26g of freeze dried powder (containing 13g of freeze dried blueberry powder and 13g of placebo comparator material) to be incorporated into the habitual diet. Dietary restrictions will be observed (i.e. avoidance of blueberry, and restricted intake of anthocyanin rich foods) for 21 days prior to the first assessment visit and throughout the study.
Intervention Type
Other
Intervention Name(s)
Control
Intervention Description
Control: 26g of placebo comparator material to be incorporated into the habitual diet. Dietary restrictions will be observed (i.e. avoidance of blueberry, and restricted intake of anthocyanin rich foods) for 21 days prior to the first assessment visit and throughout the study.
Primary Outcome Measure Information:
Title
Insulin resistance
Description
Assessed, in the fasted state, via HOMA-IR calculation in all participants; indirect assessment.
Time Frame
Chronic (0 to 6 month)
Secondary Outcome Measure Information:
Title
Insulin resistance
Description
Assessed in a sub-group via hyperinsulinemic euglycaemic clamp.
Time Frame
Chronic (0 to 6 month)
Title
Blood pressure and blood vessel regulation
Description
Measurements taken of arterial stiffness, endothelial function and blood pressure.
Time Frame
Chronic (0 to 6 month)
Title
Lung function
Description
Assessed via standard spirometry techniques and biological assessment of exhaled samples.
Time Frame
Chronic (0 to 6 month)
Title
Cognitive function
Description
Assessed via a validated cognitive test battery.
Time Frame
Chronic (0 to 6 month)
Title
Liver fat and blood flow assessment
Description
Assessment via 3T MRI in a sub-group of participants.
Time Frame
Chronic (0 to 6 month)
Title
Bio-availability
Description
Flavonoid and metabolite levels will be assessed in blood and 24 hour urine samples.
Time Frame
Chronic (0 to 6 month)
Title
Metabolite phenotype effects
Description
The gut microbiome will be assessed from faecal sample collection and the impact on metabolism and of genotype, will be assessed via a targeted approach.
Time Frame
Chronic (0 to 6 month)
Title
Acute +24 hour effect of single (26g) intervention intake, given with high fat challenge
Description
Insulin resistance, lipaemia, vascular, cognitive and lung function measured pre- and post-intervention in combination with a high fat challenge in a sub-group of participants. Urine samples and blood samples (over a 24 hour period) will be taken for biomarker analysis.
Time Frame
Chronic (0 to 6 month)

10. Eligibility

Sex
All
Minimum Age & Unit of Time
50 Years
Maximum Age & Unit of Time
74 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Men and postmenopausal women (≥ 1 year since last menstruation) 50 to 75 years old BMI of ≥ 25 kg/m2 3 characteristics of metabolic syndrome i.e: Waist circumference ≥ 102 cm for men, ≥ 88 cm for women; Triglycerides ≥ 1.7 mmol/L (or drug treatment for elevated triglycerides); HDL-cholesterol < 1.0 mmol/L for men, < 1.3 mmol/L for women (or drug treatment for low HDL-cholesterol); Blood pressure ≥ 130 mm Hg systolic and/or ≥ 85 mm Hg diastolic blood pressure; Fasting blood glucose ≥ 5.56 mmol/L Successful biochemical, haematological and urinalysis assessment at screening Exclusion Criteria: Current smokers, or ex-smokers ceasing < 6 months ago Existing or significant past medical history of vascular disease or medical conditions likely to affect the study measures Fructose intolerance or known allergies to the intervention treatments On therapeutic diets or having experienced substantial weight loss within 3 months of screening Taking flavonoid containing supplements (and unwilling to cease intake during, and 1 month preceding the trial) Planning on altering consumption of vitamin supplements / fish oil capsules during the course of the study. Prescribed hypoglycaemic, vasodilators or HRT medication. Unsatisfactory biochemical, haematological or urinary assessment at screening, or measures considered to be counter indicative for the study < 3 characteristics of the metabolic syndrome. NB: REC approved NoSA granted to include those on anti-hypertensives (29JUL2014)
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Aedin Cassidy, PhD
Organizational Affiliation
University of East Anglia
Official's Role
Principal Investigator
Facility Information:
Facility Name
Harvard School of Public Health
City
Boston
State/Province
Massachusetts
ZIP/Postal Code
02115
Country
United States
Facility Name
Addenbrooke's hospital
City
Cambridge
State/Province
Cambridgeshire
ZIP/Postal Code
CB2 0QQ
Country
United Kingdom
Facility Name
Norwich Medical School University of East Anglia
City
Norwich
State/Province
Norfolk
ZIP/Postal Code
NR4 7TJ
Country
United Kingdom
Facility Name
Norfolk and Norwich University Hospital
City
Norwich
State/Province
Norfolk
ZIP/Postal Code
NR4 7UY
Country
United Kingdom

12. IPD Sharing Statement

Citations:
PubMed Identifier
34883305
Citation
Curtis PJ, Berends L, van der Velpen V, Jennings A, Haag L, Chandra P, Kay CD, Rimm EB, Cassidy A. Blueberry anthocyanin intake attenuates the postprandial cardiometabolic effect of an energy-dense food challenge: Results from a double blind, randomized controlled trial in metabolic syndrome participants. Clin Nutr. 2022 Jan;41(1):165-176. doi: 10.1016/j.clnu.2021.11.030. Epub 2021 Nov 27.
Results Reference
derived
PubMed Identifier
31136659
Citation
Curtis PJ, van der Velpen V, Berends L, Jennings A, Feelisch M, Umpleby AM, Evans M, Fernandez BO, Meiss MS, Minnion M, Potter J, Minihane AM, Kay CD, Rimm EB, Cassidy A. Blueberries improve biomarkers of cardiometabolic function in participants with metabolic syndrome-results from a 6-month, double-blind, randomized controlled trial. Am J Clin Nutr. 2019 Jun 1;109(6):1535-1545. doi: 10.1093/ajcn/nqy380. Erratum In: Am J Clin Nutr. 2019 Nov 1;110(5):1262.
Results Reference
derived

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The Health Effects of Blueberry Anthocyanins in Metabolic Syndrome (the CIRCLES-study)

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