None listed
Conditions
Brief summary
In order to better assess the role of CPAP in mitigating cardiovascular risk factors of participants with obstructive sleep apnoea (OSA), this study aims to assess the effect of a night of active and a night of sham CPAP on beat to beat blood pressure and vascular function. To measure vascular function, non-invasive and benign ultrasound based techniques will be used to assess peripheral artery vascular function in the brachial artery, along with intracranial arterial function utilising transcranial Doppler assessments. Finally, we will measure urinary catecholamines from urine collections pre and post sleep. Blood pressure will be monitored continuously throughout the night using a finapress device while participants are simultaneously having their sleep monitored by polysomnography. The results of this study have the ability to further understand the physiological effects of missing one night of CPAP treatment in patients with OSA.
Interventions
Participants will be subjected to both active continuous positive airway pressure (CPAP) (their usual settings) and sham CPAP while undergoing polysomnography on two separate nights in a randomised order. Each night will be separated by at least one week, but no more than 6 weeks between visits. Participants will use their own clinically fitted mask (i.e. nasal mask, full face mask etc). Each sleep study will be for a duration of ~8h. The sleep study will be conducted at The Centre for Slee
Participants will be subjected to both active continuous positive airway pressure (CPAP) (their usual settings) and sham CPAP while undergoing polysomnography on two separate nights in a randomised order. Each night will be separated by at least one week, but no more than 6 weeks between visits. Participants will use their own clinically fitted mask (i.e. nasal mask, full face mask etc). Each sleep study will be for a duration of ~8h. The sleep study will be conducted at The Centre for Sleep Science at The University of Western Australia.
Sponsors
The University of Western Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
25 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
Participants will be individuals with obstructive sleep apnoea and who have been established on Continuous positive airway pressure (CPAP) therapy within the last three years. They will also need to be compliant with CPAP therapy (average nightly use > 4 hours per night at the last review). Only participants whose CPAP therapy has been shown to be effective (i.e., residual AHI <10/hr on CPAP machine download or polysomnographic assessment of control of OSA while using CPAP) will be included.
Exclusion criteria
1. Current smoker 2. Alcohol consumption more than 21 standard units per week 3. Significant cardiovascular disease including unstable angina, cardiac failure (NYHA > level 2), important arrhythmia (e.g. atrial fibrillation (AF), 2nd, 3rd degree heart block), history of myocardial infarction (MI) within last 3 months and previous history of stroke. 4. Severely and inadequately controlled hypertension (i.e. BP >180/110 mmHg). 5. Severe respiratory disease but excluding those with more than moderate obstructive lung disease i.e. reduced ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC ratio) and FEV1 < 50% or moderate restrictive lung disease i.e. FVC or total lung capacity (TLC < 50%). However stable lung disease with less severe disease can be recruited. 6. Severe nocturnal desaturation documented on polysomnography (PSG) > 2% night sleep-time with arterial oxygen saturation of <85%. 7. Central (non-obstructive) sleep apnoea (central events > 50% AHI or > 15 events/hour). 8. Predominant Cheyne-Stokes respiration. 9. Other serious medical disorders (disabling neurological disorders, life threatening malignancy, renal failure requiring dialysis, peripheral artery diseases and etc.) 10. Change of medication in the last 3 months 11. Morbid obesity (BMI> 40kg/m2). 12. OSA not primary sleep disorder, i.e. exclude if primary insomnia diagnosis, narcolepsy or primary restless legs/ periodic limb movement syndrome (PLMS). 13. Professional drivers. 14. Raynaud's phenomenon.
Outcome results
None listed