Dietary Nitrate on Blood Pressure and Cardiovascular Disease Risk Factors

Unity Health Toronto

Status and phase: Unknown; Phase 3

Conditions: Blood Pressure, High; Hypertension

Treatments: Other: High-nitrate dehydrated vegetable powder; Other: Low-nitrate dehydrated vegetable powder

Study type: Interventional

Funder types: Other

Identifiers

NCT03478631

DINO3

Details and patient eligibility

About

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.

Full 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.

Enrollment: 90 estimated patients

Sex: All

Ages: 30 to 60 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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90 participants in 2 patient groups

High Nitrate Dehydrated Vegetables

Experimental group

Description:

Participants are given high-nitrate dehydrated vegetable powders contained in opaque sachets. Participants are advised to consume three sachets per day, over the course of three meals, for 16 weeks.

Treatment:

Other: High-nitrate dehydrated vegetable powder

Low-Nitrate Dehydrated Vegetables

Active Comparator group

Description:

Participants are given low-nitrate dehydrated vegetable powders contained in three opaque sachets. Participants are advised to consume three sachets per day, over the course of three meals, for 16 weeks.

Treatment:

Other: Low-nitrate dehydrated vegetable powder