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

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ClinicalTrials.gov Identifier: NCT02035592
Recruitment Status : Completed
First Posted : January 14, 2014
Last Update Posted : September 29, 2017
Sponsor:
Collaborator:
Harvard School of Public Health
Information provided by (Responsible Party):
University of East Anglia

Tracking Information
First Submitted Date  ICMJE January 10, 2014
First Posted Date  ICMJE January 14, 2014
Last Update Posted Date September 29, 2017
Study Start Date  ICMJE January 2014
Actual Primary Completion Date November 7, 2016   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: January 10, 2014)
Insulin resistance [ Time Frame: Chronic (0 to 6 month) ]
Assessed, in the fasted state, via HOMA-IR calculation in all participants; indirect assessment.
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: January 10, 2014)
  • Insulin resistance [ Time Frame: Chronic (0 to 6 month) ]
    Assessed in a sub-group via hyperinsulinemic euglycaemic clamp.
  • Blood pressure and blood vessel regulation [ Time Frame: Chronic (0 to 6 month) ]
    Measurements taken of arterial stiffness, endothelial function and blood pressure.
  • Lung function [ Time Frame: Chronic (0 to 6 month) ]
    Assessed via standard spirometry techniques and biological assessment of exhaled samples.
  • Cognitive function [ Time Frame: Chronic (0 to 6 month) ]
    Assessed via a validated cognitive test battery.
  • Liver fat and blood flow assessment [ Time Frame: Chronic (0 to 6 month) ]
    Assessment via 3T MRI in a sub-group of participants.
  • Bio-availability [ Time Frame: Chronic (0 to 6 month) ]
    Flavonoid and metabolite levels will be assessed in blood and 24 hour urine samples.
  • Metabolite phenotype effects [ Time Frame: Chronic (0 to 6 month) ]
    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 [ Time Frame: Chronic (0 to 6 month) ]
    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.
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title  ICMJE The Health Effects of Blueberry Anthocyanins in Metabolic Syndrome (the CIRCLES-study)
Official Title  ICMJE The Effects of Blueberry Anthocyanins on Insulin Resistance and Vascular, Lung and Cognitive Function in a Population With Metabolic Syndrome.
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).
Detailed Description Not Provided
Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Condition  ICMJE
  • Insulin Resistance
  • Metabolic Syndrome X
Intervention  ICMJE
  • Other: Full dose blueberry

    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.

  • Other: Half dose blueberry

    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.

  • Other: Control

    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.

Study Arms  ICMJE
  • Active Comparator: Full dose blueberry

    26g of freeze dried blueberry powder; equivalent to 2 portions of fresh blueberries per day.

    Frequency: 26g per day.

    Total duration: 6-month.

    Intervention: Other: Full dose blueberry
  • Active Comparator: Half dose blueberry

    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.

    Intervention: Other: Half dose blueberry
  • Placebo Comparator: Control

    Matched control powder; matched for appearance, taste and sugar content.

    Frequency: 26g per day.

    Total duration: 6-month.

    Intervention: Other: Control
Publications * 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.

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status  ICMJE Completed
Estimated Enrollment  ICMJE
 (submitted: January 10, 2014)
144
Original Estimated Enrollment  ICMJE Same as current
Actual Study Completion Date  ICMJE November 7, 2016
Actual Primary Completion Date November 7, 2016   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

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)

Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 50 Years to 74 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United Kingdom,   United States
Removed Location Countries  
 
Administrative Information
NCT Number  ICMJE NCT02035592
Other Study ID Numbers  ICMJE R21478-C
Has Data Monitoring Committee No
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party University of East Anglia
Study Sponsor  ICMJE University of East Anglia
Collaborators  ICMJE Harvard School of Public Health
Investigators  ICMJE
Principal Investigator: Aedin Cassidy, PhD University of East Anglia
PRS Account University of East Anglia
Verification Date January 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP