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Effect of Black Tea on Vascular Function (Heraclitus)

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT01945970
First Posted: September 19, 2013
Last Update Posted: March 22, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Collaborator:
Sprim Advanced Life Sciences
Information provided by (Responsible Party):
Unilever R&D
September 8, 2013
September 19, 2013
December 23, 2016
February 17, 2017
March 22, 2017
September 2013
November 2013   (Final data collection date for primary outcome measure)
Flow Mediated Dilation, Acute-upon-chronic, Black Tea [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 8. ]

Flow mediated dilation (FMD) measurement included the following steps:

  • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
  • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
  • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
  • When the artery had returned to baseline a second 1 minute scan was taken
  • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
  • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
Change in flow mediated dilation from baseline on day 1 to post consumption on day 8. [ Time Frame: Day 1 and day 8 ]
The 'acute upon chronic effect' of black tea on flow mediated dilation.
Complete list of historical versions of study NCT01945970 on ClinicalTrials.gov Archive Site
  • Flow Mediated Dilation, Acute, Black Tea [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 1 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Flow Mediated Dilation, Chronic, Black Tea [ Time Frame: From before consumption day 1 to before consumption day 8. ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Flow Mediated Dilation, Acute-upon-chronic, Positive Control [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 8 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Flow Mediated Dilation, Acute, Positive Control [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 1 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Flow Mediated Dilation, Chronic, Positive Control [ Time Frame: From before consumption on day 1 to before consumption day 8 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Change in flow mediated dilation from baseline on day 1 to post consumption on day 1. [ Time Frame: Day 1 ]
    The 'acute effect' of black tea extract on flow mediated dilation.
  • Change in flow mediated dilation from post consumption on day 1 to post consumption on day 8. [ Time Frame: Day 1 and day 8 ]
    The 'chronic effect' of black tea on flow mediated dilation.
  • Change in flow mediated dilation from baseline on day 1 to post consumption on day 8. [ Time Frame: Day 1 and day 8 ]
    The 'acute upon chronic effect' of positive control on flow mediated dilation.
  • Change in flow mediated dilation from baseline on day 1 to post consumption on day 1. [ Time Frame: Day 1 ]
    The 'acute effect' of positive control on flow mediated dilation.
  • Change in flow mediated dilation from post consumption on day 1 to post consumption day 8. [ Time Frame: Day 1 and day 8 ]
    The 'chronic effect' of positive control tea extract on flow mediated dilation
  • Systolic Blood Pressure, Black Tea [ Time Frame: From before consumption on day 1 to before consumption on day 8 ]
    Change in Systolic blood pressure
  • Diastolic Blood Pressure Black Tea [ Time Frame: From before consumption on day 1 to before consumption day 8 ]
    Change in Diastolic blood pressure
  • Systolic Blood Pressure, Positive Control [ Time Frame: From before consumption (baseline) day 1 to before consumption day 8 ]
    Change in systolic blood pressure
  • Diastolic Blood Pressure, Positive Control [ Time Frame: From before consumption on day 1 to before consumption day 8 ]
    Change in Diastolic Blood pressure
  • Endothelium Independent Dilation, Acute-upon-chronic, Black Tea [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 8 ]

    FMD measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Endothelium Independent Dilation, Chronic, Black Tea [ Time Frame: From before consumption on day 1 to before consumption day 8 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Endothelium-Independent Dilation, Acute, Black Tea [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 1 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Endothelium Independent Dilation, Acute-upon-chronic, Positive Control [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 8 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Endothelium Independent Dilation, Chronic, Positive Control [ Time Frame: From before consumption on day 1 to before consumption day 8 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • Endothelium Independent Dilation, Acute, Positive Control [ Time Frame: From before consumption on day 1 to 2 hours post consumption on day 1 ]

    Flow mediated dilation (FMD) measurement included the following steps:

    • 1 minute base scan to measure the baseline diameter of artery (Resting stage)
    • 5 minutes of forearm occlusion at 300±30 mmHg (cuff occlusion stage), just below the elbow 2-5 cm from antecubital crease)
    • 4 minutes FMD scan, which started immediately after release of occlusion (reactive hyperaemia stage)
    • When the artery had returned to baseline a second 1 minute scan was taken
    • 25 µg sublingual glyceryl trinitrate (GTN) was given to the subject
    • 5 minutes GTN scan to assess the endothelium-independent dilation FMD and response to GTN was calculated as maximal percent increase in diameter above baseline (mean value of measures obtained during 1 minute before cuff inflation).
  • The effect on changes in blood pressure (systolic and diastolic will be analysed). [ Time Frame: Day 1 and day 8 ]
    Blood pressure will be measured before each FMD measurements.
  • The effects on changes in endothelium-independent dilation (after glyceryl trinitrate). [ Time Frame: Day 1 and day 8 ]
    Calculated as for endothelium dependent flow mediated dilation
 
Effect of Black Tea on Vascular Function
Randomized Double Blind Placebo Controlled Crossover Study to Assess the Effect of Black Tea on Flow-Mediated Dilation in Healthy, Non-tea Drinking Males
Epidemiological studies indicate that regular consumption of three cups of black tea per day reduces the risk of stroke or myocardial infarction. In a number of previous nutrition intervention studies tea has been shown to improve vascular function as assessed by Flow Mediated Dilation (FMD).
The current study tests a specific Black tea extract against a placebo in population that has previously show to be sensitive to the effect of black tea on Flow Mediated dilation. A tea extract that has previously been shown to improve FMD is included as the positive control.
Interventional
Not Provided
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Vascular Function
  • Other: Black tea extract
    Black tea extract
  • Other: Positive control
    Positive control
  • Other: Placebo
    Placebo
  • Experimental: Black tea extract
    Spray dried aqueous extract of a representative batch of black tea
    Intervention: Other: Black tea extract
  • Active Comparator: Positive control
    Spray dried aqueous extract of a batch of tea extract that has shown to improve FMD previously
    Intervention: Other: Positive control
  • Placebo Comparator: Placebo
    Food grade colouring, artificial tea flavour and an amount of caffeine matched to the caffeine in the Black tea extract
    Intervention: Other: Placebo
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
30
December 2013
November 2013   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Apparently healthy male volunteers with no history of cardiovascular disease
  • Having body mass index (BMI) of between 18.0 and 30.0 kg/m2 (inclusive)
  • Non-smokers (> 2 years)
  • Non-tea drinkers (less or equal 1 cup/week)
  • Limited alcohol intake (less or equal 21 units/week)
  • Systolic blood pressure less or equal 160 mmHg and/or diastolic blood pressure less or equal 100 mmHg at screening
  • Brachial artery can be imaged using ultrasound and at screening FMD value is within the expected range as judged by the PI
  • Judged to be in good health on the basis of medical history, physical examination and routine laboratory tests (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, glucose, highly sensitive C-reactive protein).
Sexes Eligible for Study: Male
40 Years to 65 Years   (Adult)
Yes
Contact information is only displayed when the study is recruiting subjects
Italy
 
 
NCT01945970
REF-BEV-1134
No
Not Provided
Not Provided
Unilever R&D
Unilever R&D
Sprim Advanced Life Sciences
Principal Investigator: Lorenzo Ghiadoni, MD University of Pisa, Internal medicine
Unilever R&D
February 2017

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