A 2 Week, Crossover Trial of Dietary Nitrate in Obstructive Sleep Apnoea Syndrome (OSAS).

Dietary Nitrate for OSAS: a Randomized, Placebo-controlled, Crossover Trial.

Acute consumption of dietary nitrate (as beetroot juice) has been shown to decrease systemic blood pressure in multiple populations as well as increase organ perfusion in areas of interest such as the pancreas and brain. Obstructive sleep apnoea syndrome (OSAS) is associated with high blood pressure, dysglycaemia and impaired vigilance. The effect of dietary nitrate in OSAS has not been reported.

Study Overview

• Status: Completed
• Conditions: Obstructive Sleep Apnoea Syndrome
• Intervention / Treatment: Dietary supplement: Dietary nitrate; Dietary supplement: Placebo

Detailed Description

Acute consumption of dietary nitrate (as beetroot juice) has been shown to decrease systemic blood pressure in multiple populations as well as increase organ perfusion in areas of interest such as the pancreas and brain. Obstructive sleep apnoea syndrome (OSAS) is associated with high blood pressure, dysglycaemia and impaired vigilance. The effect of dietary nitrate in OSAS has not been reported.

The investigators hypothesize that chronic nitrate consumption might decrease blood pressure and dysglycaemia and improve vigilance compared to a placebo beetroot juice.

This study is a randomized, double-blind placebo-controlled, crossover trial. At baseline, mid-point and endpoint ambulatory blood pressure will be assessed in conjunction with demographics, questionnaires, vigilance and blood draw. After baseline measures, each subject will be randomized to consume nitrate rich beetroot juice for 14 consecutive nights when assessments will be repeated followed by 14 nights of placebo and endpoint assessments or the converse.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Ireland
  • Dublin, Ireland, D15
    • Connolly Hospital, Blanchardstown

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Clinically stable,
• Untreated OSAS out-patients

Exclusion Criteria:

• Using continuous positive airways pressure therapy
• Pulmonary hypertension
• Active CVD
• Active musculo-skeletal conditions
• Taking vasodilators
• Diabetes mellitus

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Nitrate rich beetroot juice; Concentrated, beetroot juice is a rich source of dietary nitrate.	Dietary supplement: Dietary nitrate; 140ml of nitrate rich beetroot juice provides 12.9mmol nitrate and will be consumed on a daily basis during the intervention by the study subjects.; Other Names: Beetroot juice
Placebo Comparator: Nitrate depleted placebo beetroot juice; Placebo beetroot juice is identical to active beetroot juice in every way except nitrate content.	Dietary supplement: Placebo; 140ml of nitrate depleted beetroot juice provides 0.5mmol nitrate and will be consumed on a daily basis during the intervention by the study subjects.; Other Names: Nitrate depleted beetroot juice

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in ambulatory nocturnal blood pressure	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in 24h blood pressure	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in plasma nitrate and nitrite	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in fasting glucose	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in OSAS symptomatology	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in 2h post OGT glucose	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in overnight oximetry	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in exhaled nitric oxide	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29
Difference in vigilance scores derived from the Conner's Continuous Performance Test.	Comparison of the change after nitrate-rich beetroot juice compared to placebo.	Day 1, day 15, day 29

Collaborators and Investigators

• Sponsor: Royal College of Surgeons, Ireland
• Collaborators: University College Dublin; Connolly Hospital Blanchardstown
• Investigators: Principal Investigator: Liam Cormican, MD, Connolly Hospital

Study record dates

Study Major Dates

• Study Start: January 1, 2015
• Primary Completion (Actual): September 1, 2015
• Study Completion (Actual): September 1, 2015

Study Registration Dates

• First Submitted: January 7, 2015
• First Submitted That Met QC Criteria: July 30, 2015
• First Posted (Estimate): August 4, 2015

Study Record Updates

• Last Update Posted (Estimate): October 23, 2015
• Last Update Submitted That Met QC Criteria: October 22, 2015
• Last Verified: August 1, 2015

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Respiratory Tract Diseases; Apnea; Respiration Disorders; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Disease; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Syndrome
• Other Study ID Numbers: Chronic NO3- in OSAS

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No