Dietary Nitrate on Blood Pressure and Cardiovascular Disease Risk Factors

Hypertension Clinical Trial

Official title:

The Role of Dietary Nitrate on Blood Pressure and Cardiovascular Disease Risk Factors: a Randomized, Controlled Trial in Individuals With Elevated Blood Pressure

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT03478631
• Other study ID #: DINO3
• Status: Not yet recruiting
• Phase: Phase 3
• First received: March 20, 2018
• Last updated: March 26, 2018
• Start date: August 2018
• Est. completion date: August 2020

Study information

• Verified date: March 2018
• Source: St. Michael's Hospital, Toronto
• Contact: Elena Jovanovski, MSc
• Phone: 416 864 6060
• Email: JovanovskiE[@]smh.ca
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The project aims to determine the effect of a high-nitrate dietary intervention on blood pressure and markers of vascular function compared to a low-nitrate intervention in people with elevated blood pressure. Half of the participants will receive the high-nitrate dehydrated vegetable intervention, while the other half will receive the low-nitrate dehydrated vegetable intervention.This project will advance the current hypothesis on the therapeutic link between dietary nitrate and high blood pressure, and potentially derive impactful recommendations for individuals at risk of hypertension.

Description:

Diets rich in fruits and in particular, vegetables, reduce blood pressure (BP) and the risk of cardiovascular events. Increasingly, attention is being given to high-nitrate containing vegetables, with emerging evidence that it might represent a source of vasoactive nitric oxide. Clinical data to date uniformly suggest an acute vasoprotective role of dietary nitrate administration and a BP-lowering effect. Whether the vascular effects extend to long-term intake and in individuals with elevated blood pressure is not well known. The investigators hypothesize that consumption of a dietary intervention high in nitrate from vegetable sources will have a greater effect on BP and related vascular parameters than a similar intervention that is low in dietary nitrates.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 90
• Est. completion date: August 2020
• Est. primary completion date: August 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 30 Years to 60 Years

Eligibility

Inclusion Criteria:

• BMI 18.5-35 kg/m2

• Seated systolic blood pressure =130 and <160 mmHg

Exclusion Criteria:

• current use of antihypertensive agents

• history of major cardiovascular events in the last 1 year (stroke or myocardial infarction)

• stage II hypertension as per JNC7 criteria (systolic BP/ diastolic BP =160/100 mmHg) - angina pectoris

• gastrointestinal (i.e. inflammatory bowel disease, celiac), liver or kidney disease

• cardiac condition that compromises normal function (e.g. mitral valve disease, heart failure)

• serum triglyceride >4.5mmol/L

• major disability or disorder requiring continuous medical attention

• planned initiation in antihypertensive therapy

• herb or supplement use that may affect primary outcome

• consuming >3 servings of vegetables/day (based on semi-quantitative food frequency questionnaire)

• alcohol use >2 drinks/day

• chronic or prescribed use of medications including prescription NSAIDs, antacids, warfarin, medications affecting NO synthesis (ie. sildenafil, organic nitrates, etc)

• use of antibiotics within 3-months of the study start

• participants should also be willing to refrain from using mouthwash (ie chlorhexidine) for the duration of their participation in the study

Related Conditions & MeSH terms

• Blood Pressure, High
• Cardiovascular Diseases
• Hypertension

Intervention

Other:
• High-nitrate dehydrated vegetable powder
A mixed combination of vegetable powders that are naturally high in nitrate content, such as beet, spinach, and kale
• Low-nitrate dehydrated vegetable powder
A mixed combination of vegetable powders that are naturally low in nitrate content, such as peas, tomato, broccoli, carrots, and brussel sprouts

Locations

Country	Name	City	State
Canada	Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital	Toronto	Ontario

Sponsors (2)

Lead Sponsor	Collaborator
St. Michael's Hospital, Toronto	Canadian Institutes of Health Research (CIHR)

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Symptoms Diary	Record of any adverse symptoms experienced and the level of severity	Screening, baseline, 8 and 16 weeks
Other	Aspartate Aminotransferase (AST)	Liver function test	Screening, baseline, 8 and 16 weeks
Other	Creatinine	Kidney function test	Screening, baseline, 8 and 16 weeks
Other	Sachet Count	Record of the amount of sachets and contents returned	8 and 16 weeks
Other	7-Day Food Record	Record of food intake 7 days prior to study visit day	Baseline, 8 and 16 weeks
Other	Nitrate Food Frequency Questionnaire	Assess consumption of nitrate-rich meats and vegetables	Biweekly (screening, 0,2,4,6,8,10,12,14,16,18 weeks)
Other	Habitual Physical Activity Questionnaire	Questions to assess level of physical activity	Baseline, Week 16
Other	Body Weight	Body Weight in kg	Screening, baseline, 8 and 16 weeks
Other	24h Urinary Nitrite and Nitrate levels (exploratory outcome, TBD)	Marker of treatment compliance	16 weeks
Other	24h Urinary Potassium levels (exploratory outcome, TBD)	Urine samples collected for estimation of potassium intake	16 weeks
Other	24h Urinary Sodium levels (exploratory outcome, TBD)	Urine samples collected for estimation of sodium intake	16 weeks
Other	Cyclic guanosine monophosphate (cGMP) (exploratory outcome, TBD)	Change in cGMP vs. control at 16 weeks	Baseline and 16 weeks
Other	Plasma nitrate/nitrite (exploratory outcome, TBD)	Change in plasma nitrate and nitrite vs. control at 16 weeks	Baseline and 16 weeks
Primary	Systolic Blood Pressure	Change in systolic blood pressure vs. control at 16 weeks	Baseline, 8 and16 weeks
Secondary	Mean 24h and Daytime Ambulatory Systolic, Diastolic and Mean Arterial Blood Pressure	Change in mean 24h and daytime ambulatory systolic, diastolic and mean arterial blood pressure vs. control at 16 weeks	Baseline and 16 weeks
Secondary	Aortic Systolic and Diastolic Blood Pressure	Change in aortic systolic and diastolic blood pressure vs. control at 16 weeks	Baseline, 8 and 16 weeks
Secondary	Pulse Wave Velocity (PWV)	Change in PWV vs. control at 16 weeks	Baseline and 16 weeks
Secondary	Augmentation Index (AI)	Change in AI vs. control at 16 weeks	Baseline, 8 and 16 weeks
Secondary	High Sensitivity C-reactive protein (hs-CRP)	Change in hs-CRP vs. control at 16 weeks	Baseline and 16 weeks
Secondary	Plasma Lipids	Change in Total-C, LDL-C, HDL-C vs. control at 16 weeks	Baseline and 16 weeks