None listed
Conditions
Brief summary
Obstructive sleep apnea (OSA) is a common sleep disorder, and is linked with excessive and inappropriate sleepiness, impaired cognition, increased risk of motor vehicle crashes and workplace accidents. However, not all patients with OSA display daytime impairments and it is still not completely known how OSA affects the brain. A key to understanding this is by investigating the brain activity of patients with OSA, and how this may change following CPAP therapy, the gold standard clinical treatment for OSA. This can be easily done through non-invasive EEG recordings from electrodes placed on the scalp that are a routine part of sleep studies when screening for OSA. This study uses advanced high-density electroencephalography (hdEEG) to investigate whether areas of ‘tired’ neurons that fall asleep in the awake brain underlie daytime impairments in OSA. The purpose of this study is to examine the effect of regular CPAP use versus short-term CPAP withdrawal on daytime function and brain wave activity recorded in patients diagnosed with moderate to severe OSA. We will investigate brain activity during sleep and during awake daytime performance testing.
Interventions
The study intervention, continuous positive airway pressure (CPAP) therapy, is the routine gold standard treatment for obstructive sleep apnea. Its mode of delivery is through a CPAP device and a face and/or nasal mask worn by the patient nightly whilst sleeping. The study consists of a randomised crossover design with overnight use of therapeutic CPAP (ie. the 'CPAP on' condition) or temporary treatment withdrawal (ie. the 'CPAP off' condition, duration of withdrawal: 7-10 days). These conditio
The study intervention, continuous positive airway pressure (CPAP) therapy, is the routine gold standard treatment for obstructive sleep apnea. Its mode of delivery is through a CPAP device and a face and/or nasal mask worn by the patient nightly whilst sleeping. The study consists of a randomised crossover design with overnight use of therapeutic CPAP (ie. the 'CPAP on' condition) or temporary treatment withdrawal (ie. the 'CPAP off' condition, duration of withdrawal: 7-10 days). These conditions will be allocated in random order. The experimental visit comprises 2 continuous nights: 1 baseline PSG night with standard laboratory PSG setup, and 1 night with a high-density EEG sensor cap). The high-density EEG sensornet cap comprises 256 interconnected scalp EEG electrodes worn on the head. It records brain activity. The cap will be applied in the morning of the 2nd day of the experimental visit, and will be kept on throughout the day and overnight. The sensornet cap will be removed when the final block of neurocognitive assessments is completed on the morning of the 3rd day. Participants will be given an 8-hour sleep opportunity on each night. During the 'CPAP on' condition, the CPAP device will be used for the entire duration of sleep opportunity, with a dedicated and trained overnight sleep technologist providing support to maximise adherence. Neurocognitive assessments and driving simulators will be administered on the 2nd day of the experimental visit. The total duration of neurocognitive assessments and driving simulators administered on the 2nd day is 7.0 hours. The first and last blocks of the day (ie. Baseline block and block T4, respectively) involve 30 min of neurocognitive assessments each. Blocks T1, T2 and T3 involve a 90 min driving simulator, followed by 30 min of neurocognitive assessments. There will be a 1-week washout period between experimental visits.
Sponsors
Woolcock Institute of Medical Research
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
35 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
The participant's apnea-hypopnea index (AHI) must be greater than or equal to 15/hr to be eligible for the study. The symbol has been replaced with text below. ____________________________ Males and females; Community-dwelling aged 35-65 years; Polysomnography confirmed moderate to severe OSA based on the apnea-hypopnea index (AHI) greater than or equal to 15/hr; Able to give informed consent; Fluent in English; Established CPAP users for a duration of at least 3 months (on average 4 hours use per night on at least 5 nights per week) Ability to perform neurobehavioural tests and driving simulator task. Current driver’s license Vulnerable to driving impairment without CPAP therapy/upon withdrawal of therapy, Assessed via positive response(s) to questions reporting driving accidents or impairments prior to established CPAP therapy, and/or physician's opinion.
Exclusion criteria
Clinically significant co-morbidity; Major neurological problems (e.g. stroke, epilepsy, head injury); Severe mental health disorder (e.g. current major depression, schizophrenia, bipolar disorder); Regular use of sleep-affecting medication; benzodiazepines, opioids, antidepressants. Shift worker or have traveled overseas within the last 2 weeks. Professional drivers. Sleep physician has advised against CPAP withdrawal
Outcome results
None listed