None listed
Conditions
Brief summary
Obstructive sleep apnoea (OSA) is increasingly recognized to be a risk factor for cardiovascular disease. Case reports have shown that these patients can manifest as suspected angina with no obstructive coronary artery disease (NOCAD). Recently, this condition has been demonstrated to be associated with coronary microvascular dysfunction and vasospastic angina in the Chinese and Japanese population. This association is unknown in the Australian population. The underlying mechanism remains poorly understood and appropriate therapies are limited. We will examine the relationship between symptomatic angina with NOCAD and OSA. The planned projects will provide more insights into the relationship between OSA and coronary/peripheral haemodynamics as well as whether therapy for OSA impacts on the angina burden.
Interventions
Participants with angina and no obstructive coronary artery disease from NOCAD1 study will be screened and recruited. Recruited participants will undergo type 2 ambulatory sleep study at participants' residence for the diagnosis of obstructive sleep apnoea.
Participants who have obstructive sleep apnoea and fulfilled the study inclusion/exclusion criteria as outlined for CPAP therapy will be randomly assigned to either "initial CPAP therapy" or "delayed CPAP therapy (no CPAP)" for 6 months, fo
Participants with angina and no obstructive coronary artery disease from NOCAD1 study will be screened and recruited. Recruited participants will undergo type 2 ambulatory sleep study at participants' residence for the diagnosis of obstructive sleep apnoea. Participants who have obstructive sleep apnoea and fulfilled the study inclusion/exclusion criteria as outlined for CPAP therapy will be randomly assigned to either "initial CPAP therapy" or "delayed CPAP therapy (no CPAP)" for 6 months, followed by crossover between group's therapy for further 6 months to assess the difference in effects on angina burden and quality of life. Participants on CPAP therapy will received autoPAP (Philips Respironics, Murrayville, PA) for 1 week, followed by fixed CPAP pressure, set at 90th percentile of autoPAP pressure, as determined by Sleep Physician. Delivery of CPAP device and its accessories by Philips SleepEasy Device Consultant, including education and supports in conjunction with a Sleep Physician. This will take place at the Lyell McEwin Hospital Cardiology Clinical Trial Unit. Data will be available electronically via remote downloading using Encoreanywhere program. Participant's adherence is monitored by accessing device analytics which will be downloaded remotely. Satisfactory adherence towards CPAP therapy will be assessed by Sleep Physician at 1 months, 3 months and 6 months. Minimum amount of usage time should be > 4 hours per night. Participants will be contacted to troubleshoot any difficulties and if any problems arose. There will be 6 months of no CPAP therapy prior to follow-up outcome assessment after cessation of CPAP therapy.
Sponsors
University of Adelaide
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Met NOCAD1 study inclusion criteria: - Clinical diagnosis of angina - Persistent angina - Coronary angiography demonstrating normal or no obstructive coronary disease (<50% diameter stenosis) 2. Participants for CPAP therapy with obstructive sleep apnoea diagnosis - AHI>20 - AHI<20; REM-AHI>45 3. Patients are able and willing to give appropriate informed consent.
Exclusion criteria
1. Met NOCAD1 study exclusion criteria: - Admission for an acute coronary syndrome within the preceding month - Prior coronary artery bypass grafting - Contra-indications to coronary haemodynamic assessment - patients with permanent pacemaker or de brillator, severe renal or hepatic insu ciency, severe asthma, left ventricular systolic dysfunction (ejection fraction <50%) - Alternative coronary explanations for the chest pain - obstructive coronary artery disease (Flow limiting coronary stenosis i.e. derived fractional flow reserve (FFR) <0.80), spontaneous coronary spasm (but not catheter related spasm), spontaneous coronary artery dissection - Other cardiovascular disorders - pulmonary hypertension, pulmonary embolism, hypertrophic cardiomyopathy, or valvular heart disease. 2. Non-English speaking patient 3. Unable to give consent due to cognitive impairment 4. Patient is or may be pregnant 5. Severe comorbidity with severe disability or likelihood of death 6. Significant memory, perceptual or behavioural disorder 7. Neurological deficit preventing self administration of CPAP mask 8. Contra-indication to CPAP use e.g. pneumothorax 9. Severe respiratory disease defined as - Severe chronic obstructive pulmonary disease (FEV1/FVC<70% and FEV1 <50% predicted) - Resting SaO2 <90%. 10. Prior use of CPAP treatment of OSA 11. Increased risk of a sleep-related accident and/or excessive daytime sleepiness, defined by any one of the following: - Driver occupation (eg truck, taxi) - ‘fall asleep’ accident or ‘near miss’ accident in previous 12 months - High Epworth Sleepiness Scale score (>15) 12. Severe nocturnal desaturation documented during sleep study as >10% overnight recording time with arterial oxygen saturation of <80% 13. Cheyne-Stokes Respiration (CSResp)
Outcome results
None listed