Clinical trial NCT02515071: A 2 Week, Crossover Trial of Dietary Nitrate in Obstructive Sleep Apnoea Syndrome (OSAS).
Official title: Dietary Nitrate for OSAS: a Randomized, Placebo-controlled, Crossover Trial.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Obstructive Sleep Apnoea Syndrome
Lead sponsor: Royal College of Surgeons, Ireland
Sponsor class: OTHER
Collaborators: name: University College Dublin
name: Connolly Hospital Blanchardstown
First posted: 2015-08-04
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: SUPPORTIVE_CARE

Brief summary: 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.

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.

Eligibility criteria: 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

Primary outcomes:
measure: Difference in ambulatory nocturnal blood pressure
timeFrame: Day 1, day 15, day 29
Secondary outcomes:
measure: Difference in 24h blood pressure
timeFrame: Day 1, day 15, day 29
measure: Difference in plasma nitrate and nitrite
timeFrame: Day 1, day 15, day 29
measure: Difference in fasting glucose
timeFrame: Day 1, day 15, day 29
measure: Difference in OSAS symptomatology
timeFrame: Day 1, day 15, day 29
measure: Difference in 2h post OGT glucose
timeFrame: Day 1, day 15, day 29
measure: Difference in overnight oximetry
timeFrame: Day 1, day 15, day 29
measure: Difference in exhaled nitric oxide
timeFrame: Day 1, day 15, day 29
measure: Difference in vigilance scores derived from the Conner's Continuous Performance Test.
timeFrame: Day 1, day 15, day 29
Other outcomes:
Locations:
city: Dublin
country: Ireland
facility: Connolly Hospital, Blanchardstown
Study officials:
affiliation: Connolly Hospital
name: Liam Cormican, MD
role: PRINCIPAL_INVESTIGATOR
References: