The Chronic Effects of Beetroot Juice in Hypertensive Subjects

Study Overview
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Brief Summary
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We are interested in the effect of diet on blood pressure. Our previous research has shown that beetroot juice lowers blood pressure in healthy people. We now want to see if beetroot juice has this effect in people with high blood pressure. Beetroot juice is naturally rich in nitrate (also found in most other vegetables but particularly in green leafy vegetables). We think that it is the nitrate that lowers the blood pressure.

Official Title
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The Chronic Effects of Beetroot Juice on Circulating Plasma Nitrate and Nitrite Levels and Blood Pressure in Hypertensive Subjects

Conditions
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Hypertension

Intervention / Treatment
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* Dietary Supplement: beetroot juice
* Dietary Supplement: Nitrate-free beetroot juice


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: A subject will be eligible for inclusion in this study only if all of the following criteria apply: Healthy adult male and females between 18 and 85 years of age, inclusive. To be eligible, female subjects will be required to state that they are not pregnant, and will not become pregnant during the course of the study. Body mass index (BMI) between 18 and 40 kg/m2 A signed and dated written informed consent prior to admission to the study The subject is able to understand and comply with protocol requirements, instructions and protocol---stated restrictions. and either of the following categories of blood pressure Category 1---Pre---hypertensive SBP 130---139 or DBP 85---89 on no antihypertensives and will not commence antihypertensives during the course of the study. Category 2---Grade 1 hypertensive SBP 140---159 or DBP 90---99 on no anti---hypertensives, no target organ damage (TOD), low cardiovascular disease (CVD) risk Category 3---Uncontrolled severe resistant (Grade 3) hypertensive with evidence of difficulty treating to target BP (140/85 or 130/80), with satisfactory adherence to at least one antihypertensive, but insufficient efficacy or intolerance of medications. (Category 3 patients may also be on aspirin and/or a stable dose of cholesterol---lowering medications e.g statins). Exclusion Criteria: A subject will not be eligible for inclusion in this study if any of the following criteria apply: History of symptomatic coronary artery disease, stroke, or other known atherosclerotic disease. History of chronic viral hepatitis (including presence of hepatitis B surface antigen or hepatitis C antibody), or other chronic hepatic disorders. History of increased liver function tests (ALT, AST) due to acute or chronic liver conditions, 3x above the upper limit of normal or bilirubin 1.5x above the upper limit of normal at screening. Renal impairment with creatinine clearance (eGFR) of <50 ml/min at screening. Current poorly controlled diabetes mellitus, defined as HbA1c >10% at Screen. Subjects with LDLc, >7.5 mmol/l. Fasting TG level >6mmol/l. History of heart failure defined as NYHA class II --- IV or those with known severe LV dysfunction (EF<30%) regardless of symptomatic status History of malignancy within the past 5 years, other than non---melanoma skin cancer. Current life---threatening condition other than vascular disease (e.g., very severe chronic airways disease, HIV positive, life---threatening arrhythmias) that may prevent a subject from completing the study. Alcohol or drug abuse within the past 6 months. Use of an investigational device or investigational drug within 30 days or 5 half---lives (whichever is the longer) preceding the first dose of study medication. Subjects who will commence or who are likely to commence treatment with non---steroidal anti--- inflammatory drugs (NSAIDs) (other than aspirin), from screening until study completion. Any non---stable dosing of ongoing medication regimens throughout the study trial. The subject has a three---month prior history of regular alcohol consumption exceeding an average weekly intake of > 28 units (or an average daily intake of greater than 3 units) for males, or an average weekly intake of > 21 units (or an average daily intake of greater than 2 units) for females. 1 unit is equivalent to a half---pint (284mL) of beer/lager; 25mL measure of spirits or 125mL of wine; or a positive alcohol breath test at the screening visit A positive urine test for drugs of abuse (not related to known medications the subject is taking, i.e., codeine for pain management) or alcohol at screening or prior to study medication administration. Any other subject whom the Investigator deems unsuitable for the study (e.g., due to either medical reasons, laboratory abnormalities, expected study medication noncompliance, or subject's unwillingness to comply with all study---related study procedures). Subjects with rheumatoid arthritis, connective tissue disorders and other conditions known to be associated with chronic inflammation (e.g. Inflammatory Bowel Disease). Subjects with any acute infection, or significant trauma (burns, fractures). Subjects who have donated more than 500 mL of blood within 56 days prior to the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Beetroot Juice<br> | Dietary Supplement: beetroot juice<br>* Beetroot juice 4 weeks 250ml daily<br>|
| Placebo Comparator: Nitrate-free beetroot juice<br> | Dietary Supplement: Nitrate-free beetroot juice<br>* Nitrate-free beetroot juice 4 weeks 250ml daily<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in Change in Clinic Systolic Blood Pressure From Baseline |  | 4 weeks | 
| Difference in Change in Clinic Diastolic Blood Pressure From Baseline |  | 4 weeks | 
| Difference in Change in Ambulatory Systolic Blood Pressure From Baseline |  | 4 weeks | 
| Difference in Change in Ambulatory Diastolic Blood Pressure From Baseline |  | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in Change in Plasma Nitrite Concentration From Baseline |  | 4 weeks | 
| Difference in Change in Endothelial Function From Baseline | as measured by flow-mediated dilatation [%change in diameter of vessel] - an increase in diameter demonstrates an improvement in endothelial function | 4 weeks | 
| Difference in Change in Arterial Stiffness From Baseline | carotid-femoral pulse wave velocity [m/s] measured by Vicorder | 4 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hypertension, nitrite, blood pressure, endothelial function