Obstructive Sleep Apnoea Syndrome
Conditions
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.
Interventions
DIETARY_SUPPLEMENTDietary 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.
DIETARY_SUPPLEMENTPlacebo
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.
Sponsors
University College Dublin
Connolly Hospital Blanchardstown
Royal College of Surgeons, Ireland
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SUPPORTIVE_CARE
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Difference in ambulatory nocturnal blood pressure | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Difference in plasma nitrate and nitrite | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in fasting glucose | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in OSAS symptomatology | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in 24h blood pressure | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in overnight oximetry | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in exhaled nitric oxide | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in vigilance scores derived from the Conner's Continuous Performance Test. | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
| Difference in 2h post OGT glucose | Day 1, day 15, day 29 | Comparison of the change after nitrate-rich beetroot juice compared to placebo. |
Countries
Ireland
Outcome results
None listed