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Trial registered on ANZCTR


Registration number
ACTRN12617000336381
Ethics application status
Approved
Date submitted
27/02/2017
Date registered
3/03/2017
Date last updated
11/08/2022
Date data sharing statement initially provided
11/03/2019
Date results information initially provided
11/08/2022
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effects of continuous positive airway pressure (CPAP) treatment on brain activity during sleep in obstructive sleep apnea (OSA).
Scientific title
The effects of continuous positive airway pressure (CPAP) treatment on brain activity during sleep in obstructive sleep apnea (OSA): A high-density electroencephalography (EEG) investigation
Secondary ID [1] 290607 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obstructive sleep apnea 301096 0
sleep disorders 301097 0
Condition category
Condition code
Respiratory 300869 300869 0 0
Sleep apnoea
Neurological 301855 301855 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Patients with a confirmed diagnosis of OSA will undergo overnight sleep study (polysomnography, PSG) with simultaneous high density EEG recordings of brain activity before and after 3 months of continuous positive airway pressure (CPAP) treatment. CPAP is the current gold-standard treatment for OSA. Participants will follow the routine clinical care pathway: this includes 1) mask fitting and CPAP education session in the afternoon followed by an overnight in-lab CPAP titration study that night, then follow up care with the CPAP Educator to monitor adherence either in person or over the phone during the treatment period approximately at weeks 2, 6 and 12 weeks after initiating treatment .
No parameters of the treatment are determined based on participation in this study. Study participants undergo CPAP treatment as prescribed by their treating physician .
Intervention code [1] 296470 0
Not applicable
Comparator / control treatment
No control group. Patients are being followed on their routine clinical pathway for CPAP use, and will be assessed before and after CPAP treatment. This is not a clinical trial.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 300278 0
Regional distribution of electroencephalography (EEG) spectral power during sleep as measured by high-density EEG recordings during overnight polysomnography (PSG, sleep study).
Timepoint [1] 300278 0
Change following 3 months of treatment with CPAP, relative to baseline measures.
Primary outcome [2] 301280 0
Regional distribution of sleep spindle events during NREM sleep as measured by high-density EEG recordings during overnight PSG
Timepoint [2] 301280 0
Change following 3 months CPAP treatment, relative to baseline measures.
Primary outcome [3] 301300 0
EEG slowing during resting wakefulness, as measured using high-density EEG recordings during a Karolinska Drowsiness Test
Timepoint [3] 301300 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [1] 329591 0
Objective sleep quality during overnight PSG. Sleep will be staged and scored by a trained sleep technician. Sleep efficiency will be calculated by quantifying the proportion of time spent asleep between Lights Out and Lights On.
Timepoint [1] 329591 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [2] 329592 0
Sleep apnea severity measured by overnight PSG. Sleep will be staged and scored by a trained sleep technician. Abnormal sleep disordered breathing events identified will be quantified per hour of sleep.
Timepoint [2] 329592 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [3] 329593 0
Sleep stages during all-night PSG
Timepoint [3] 329593 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [4] 329594 0
Heart rate variability as measured by overnight electrocardiography (ECG).
Timepoint [4] 329594 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [5] 329652 0
Sustained attention using the 10-minute psychomotor vigilance task (PVT).
Timepoint [5] 329652 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [6] 332265 0
Overnight declarative memory consolidation using a 32-word pair learning task.
Timepoint [6] 332265 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [7] 332266 0
Overnight declarative memory consolidation using a novel word learning task which includes a lexical decision making task
Timepoint [7] 332266 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [8] 332267 0
Overnight procedural memory consolidation using a finger tapping sequence task
Timepoint [8] 332267 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [9] 332268 0
An internally developed and validated neurobehavioural performance test battery sensitive to the effects of untreated OSA and response to treatment will be administered to measure working memory using the n-back task.
Timepoint [9] 332268 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [10] 332269 0
An internally developed and validated neurobehavioural performance test battery sensitive to the effects of untreated OSA and response to treatment will be administered to measure executive function using the Stroop test.
Timepoint [10] 332269 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [11] 332310 0
An internally developed and validated neurobehavioural performance test battery sensitive to the effects of untreated OSA and response to treatment will be administered to measure visuo-spatial scanning using the letter cancellation task.
Timepoint [11] 332310 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [12] 332311 0
Resting wake EEG activity (recorded during the Karolinska Drowsiness Test) administered before and after overnight sleep recordings
Timepoint [12] 332311 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [13] 332312 0
Symptoms of subjective sleepiness measured using the Epworth sleepiness scale
Timepoint [13] 332312 0
Change following 3 months CPAP treatment, relative to baseline measures.
Secondary outcome [14] 332313 0
Subjective ratings of mood using the Depression Anxiety and Stress Scale
Timepoint [14] 332313 0
Change following 3 months CPAP treatment, relative to baseline measures.

Eligibility
Key inclusion criteria
A diagnosis of moderate OSA defined by an apnea-hypopnea index (AHI) of greater than 15/hr as measured by PSG and confirmed by sleep physician. Participants must be recommended for CPAP treatment by their treating physician and be willing to commence 3 months of CPAP use. Participants must fluent in English and also have the ability to perform neurobehavioural tests and provide informed consent.
Minimum age
40 Years
Maximum age
65 Years
Sex
Males
Can healthy volunteers participate?
No
Key exclusion criteria
Clinically significant co-morbidity; history of head injury or psychiatric/neurological disorder (including stroke); use of CNS active agents; heavy alcohol consumption (40g daily); current shift-worker or travelled overseas within the last 2 weeks; previously used CPAP.

Study design
Purpose
Duration
Selection
Timing
Statistical methods / analysis
The aim of this pilot study is to evaluate changes in neurophysiological, clinical, cognitive and physiological outcomes in patients with obstructive sleep apnoea following 3 months of standard clinical treatment with continuous positive airway pressure (CPAP).

We aim to evaluate differences pre-to-post treatment for the following outcome variables:

i) Changes in electroencephalography (EEG) spectral power and waveform features (e.g. sleep spindles, K complexes, slow waves) as measured by high-density EEG recording equipment. Quantitative EEG analysis techniques will be applied to all sleep and wake recordings after identification and exclusion of artefacts. Sleep stage specific power spectra, SWA, sleep spindle characteristics and scaling exponents from detrended fluctuation analysis will be quantified. Regional analysis of high density EEG data will be performed through EGI Netstation software, PhiTools PRANA and MATLAB software.


ii) Sleep macroarchitecture (e.g. total sleep time, sleep efficiency, arousals, apnea hypopnea index, etc.) as measured by polysomnography (PSG). All PSG variables will be scored by an experienced sleep technician using PhiTools PRANA software.

iii) Performance on neurocognitive measures of memory, attention, working memory and executive functioning. Raw scores and standardized z-scores based on age and education normative data will be calculated.

iv) Heart rate variability analysis will be conducted using PRANA using an all-night ECG signal recorded during overnight PSG

v) Subjective ratings of mood and sleep as measured by self-report questionnaires.

Data entry will be performed by suitably qualified staff, supervised by the study manager. Statistical tests will be paired t-tests to examine at pre and post treatment changes in outcomes measures. Associations between sleep physiological measures and cognitive/mood outcomes will also be explored with correlational analyses.

Statistical analysis will be performed using SPSS.

This is a small pilot study. It is not a clinical trial. We aim to recruit 12 participants for pilot data and feasibility in order to inform potential larger trials.


Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
1/03/2017
Date of last participant enrolment
Anticipated
2/12/2019
Actual
29/03/2018
Date of last data collection
Anticipated
2/03/2020
Actual
23/08/2018
Sample size
Target
14
Accrual to date
Final
15
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment hospital [1] 6976 0
Woolcock Institute of Medical Research - Glebe
Recruitment postcode(s) [1] 14679 0
2037 - Glebe

Funding & Sponsors
Funding source category [1] 295037 0
Other
Name [1] 295037 0
CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research
Country [1] 295037 0
Australia
Primary sponsor type
Other
Name
Woolcock Institute of Medical Research
Address
431 Glebe Point Road
Glebe
NSW 2037
Country
Australia
Secondary sponsor category [1] 294607 0
None
Name [1] 294607 0
Address [1] 294607 0
Country [1] 294607 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296395 0
University of Sydney Human Research Ethics Committee
Ethics committee address [1] 296395 0
Research Integrity & Ethics Administration
Level 2, Margaret Telfer Building (K07)
The University of Sydney
NSW 2006 Australia
Ethics committee country [1] 296395 0
Australia
Date submitted for ethics approval [1] 296395 0
08/07/2016
Approval date [1] 296395 0
19/10/2016
Ethics approval number [1] 296395 0
2016/712

Summary
Brief summary
This research study which will investigate the effect of continuous positive airway pressure (CPAP) treatment on brain wave activity recorded using high density electroencephalography (EEG) in patients diagnosed with moderate to severe obstructive sleep apnea. The study will examine changes in sleep and wake brain activity profiles and how these may relate to neurobehavioural function including memory following CPAP treatment.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 70698 0
Dr Angela D'Rozario
Address 70698 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe NSW 2037
Country 70698 0
Australia
Phone 70698 0
+61291140435
Fax 70698 0
Email 70698 0
angela.drozario@sydney.edu.au
Contact person for public queries
Name 70699 0
Dr Angela D'Rozario
Address 70699 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe NSW 2037
Country 70699 0
Australia
Phone 70699 0
+61291140435
Fax 70699 0
Email 70699 0
angela.drozario@sydney.edu.au
Contact person for scientific queries
Name 70700 0
Dr Angela D'Rozario
Address 70700 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe NSW 2037
Country 70700 0
Australia
Phone 70700 0
+61291140435
Fax 70700 0
Email 70700 0
angela.drozario@sydney.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
IPD will not be available


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseRegion-specific changes in brain activity and memory after continuous positive airway pressure therapy in obstructive sleep apnea: a pilot high-density electroencephalography study.2023https://dx.doi.org/10.1093/sleep/zsad255
N.B. These documents automatically identified may not have been verified by the study sponsor.