Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12606000486527
Ethics application status
Approved
Date submitted
16/10/2006
Date registered
24/11/2006
Date last updated
7/07/2022
Date data sharing statement initially provided
7/07/2022
Date results information initially provided
7/07/2022
Type of registration
Retrospectively registered

Titles & IDs
Public title
Measurement location for the indices of obstructive apnea / hypopnea frequency during Continuous Positive Airway Pressure (CPAP) therapy
Scientific title
The effect of location of airflow measurement on the ability to assess Apnea Hypopnea Index (AHI) during Continuous Positive Airway Pressure (CPAP) therapy in patients with Obstructive Sleep Apnea (OSA) undergoing subtherapeutic CPAP and AutoCPAP therapy.
Secondary ID [1] 288426 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obstructive Sleep Apnea 1463 0
Condition category
Condition code
Respiratory 1559 1559 0 0
Sleep apnoea

Intervention/exposure
Study type
Observational
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Subjects will receive an identical two-night titration protocol in random order up to 3 weeks apart. On one night, an auto-adjusting CPAP device will automatically titrate pressure throughout the night within the range of 4cmH2O – 20cmH2O (cmH2O is a centimeter (centimetre) of water used to determine pressures during mechanical ventilation). On the other night, sub-therapeutic pressure will be delivered with the same device set in fixed pressure mode (2/3 of the subject’s currently prescribed CPAP level (either home fixed CPAP level or the 95th percentile of pressure on current AutoCPAP device)). Subjects will undergo full polysomnography with additional flow measurements from four sites: mask, nares, CPAP machine airflow outlet and the analogue output of the CPAP device.There is no control group in this study. Auto-titrating CPAP therapy is increasingly used to treat sleep disordered breathing, however, the standard care remains fixed pressure CPAP therapy. This is an observational study as both conditions under which data is collected in this study represent actual clinical presentations of clinical patients receiving CPAP therapy.
Intervention code [1] 1402 0
None
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 2154 0
Assessment of differences in Apnea Hypopnea Index (AHI) measured at four sites during overnight polysomnography (PSG) of subjects established on CPAP therapy. AHI will be measured during a two-night titration protocol (random order) using polysomnography in the sleep laboratory. Subjects will be connected to the CPAP device for the entirety of the PSG recording on both nights.
Timepoint [1] 2154 0
Polysomnography data will be recorded from Lights Out to Lights On (approximately 8 hour recording) during overnight PSG.
Secondary outcome [1] 3741 0
Sleep architecture
Timepoint [1] 3741 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [2] 3742 0
Sleep efficiency
Timepoint [2] 3742 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [3] 3743 0
Total sleep time
Timepoint [3] 3743 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [4] 3744 0
Arousal index – cortical (EEG) and autonomic (Pulse Transit Time)
Timepoint [4] 3744 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [5] 3745 0
Flow limitation events (frequency of oxygen desaturation of >3% per hour during sleep)Minimum oxygen saturation during sleep
Timepoint [5] 3745 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [6] 3746 0
Autoset T data
Timepoint [6] 3746 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [7] 3747 0
Optimum CPAP Pressure
Timepoint [7] 3747 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.
Secondary outcome [8] 3748 0
Near infra red spectroscopy data (cerebral blood volume/cerebral oxygen saturation).
Timepoint [8] 3748 0
Secondary outcomes will be measured throughout the entire 8 hour PSG recording on both nights during a two-night protocol (random order) in the sleep laboratory.

Eligibility
Key inclusion criteria
Subjects must satisfy the following inclusion criteria:Previously diagnosed with moderate-severe obstructive sleep apnea (RDI>15)Compliant CPAP use for at least 3 months durationCompliance: CPAP use > 4 hours per night for at least 5 nights per week No significant problems with CPAP therapy such as mask/mouth leak or severe nasal congestion. English speaking.
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Other sleep disorders including:PLMD Untreated RLS >10 Central apnoeas/hr on diagnostic sleep studyNeurological disordersPsychiatric disordersSignificant medical complaint including:Severe cardiovascular disease Congestive heart failure Significant lung disease (e.g., chronic obstructive pulmonary disease) Daytime hypoxemia and respiratory failure from any cause Prominent nocturnal desaturation other than from OSA (e.g., obesity hypoventilation syndrome).

Study design
Purpose
Screening
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
8/11/2005
Actual
8/11/2005
Date of last participant enrolment
Anticipated
Actual
11/04/2006
Date of last data collection
Anticipated
Actual
28/04/2006
Sample size
Target
34
Accrual to date
Final
34
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 1700 0
Commercial sector/Industry
Name [1] 1700 0
DiagnoseIT Pty Ltd
Country [1] 1700 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
DiagnoseIT Pty Ltd, Sydney, NSW, Australia
Address
PO Box 36 Tintenbar
NSW 2478
Country
Australia
Secondary sponsor category [1] 1500 0
None
Name [1] 1500 0
NIL
Address [1] 1500 0
Country [1] 1500 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 3154 0
Sydney South West Area Health Service
Ethics committee address [1] 3154 0
Level 11, KGV Building Missenden Road CAMPERDOWN NSW 2050
Ethics committee country [1] 3154 0
Australia
Date submitted for ethics approval [1] 3154 0
Approval date [1] 3154 0
03/08/2005
Ethics approval number [1] 3154 0
X05-0176

Summary
Brief summary
Subjects who have been using chronic CPAP therapy will be invited to participate in the study. The study will take place after the subjects have been instructed on the details of the trial and have provided informed consent. Subjects are randomised to one of two nights in the sleep laboratory. Under polysomnography and using an auto-titrating CPAP (AutoCPAP) systems, the subjects will be studied either under a sub-therapeutic pressure level for one night of recording (simulating a sub-standard therapy night – encountered by clinical patients), or on the AutoCPAP device in the therapeutic auto-titrating mode (which is also a commonly applied therapeutic device). The study is observational in that the purpose and endpoints are collected as described below, under conditions in the laboratory simulating ‘normal’ clinical occurrences. Sleep and breathing parameters will be collected using standard laboratory methodologies, with the addition of flow measurement from four different sites: nares via a cannula; the CPAP machine flow outlet; the electronic output from the CPAP machine and the standard nasal mask via an oxygen port. Integrity of the flow signal as well as the presence of ‘break-through’ apnea / hypopnea phenomena are evaluated.
Trial website
Trial related presentations / publications
Denotti, A. L., Wong, K. K., Dungan, G. C., 2nd, Gilholme, J. W., Marshall, N. S. and Grunstein, R. R. Residual sleep-disordered breathing during autotitrating continuous positive airway pressure therapy. Eur Respir J, 2012, 39: 1391-7.
Public notes

Contacts
Principal investigator
Name 27336 0
Prof Ronald R Grunstein
Address 27336 0
Woolcock Institute
PO Box M77 Missenden Road
Sydney
2050
Country 27336 0
Australia
Phone 27336 0
0291140438
Fax 27336 0
0291140014
Email 27336 0
[email protected]
Contact person for public queries
Name 10591 0
Dr Angela D'Rozario
Address 10591 0
PO Box M77
Missenden Road
Camperdown NSW 2050
Country 10591 0
Australia
Phone 10591 0
0291140435
Fax 10591 0
0291140014
Email 10591 0
[email protected]
Contact person for scientific queries
Name 1519 0
Dr Angela D'Rozario
Address 1519 0
PO Box M77
Missenden Road
Camperdown NSW 2050
Country 1519 0
Australia
Phone 1519 0
0291140435
Fax 1519 0
0291140010
Email 1519 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Individual participant underlying published results only.
When will data be available (start and end dates)?
Data will be made available upon request, after publication, with no end date determined.
Available to whom?
Data will be made available upon request, after publication and will be determined upon negotiation with researchers who provided a methodologically sound proposal.
Available for what types of analyses?
Any purpose.
How or where can data be obtained?
Secure data transfer and signed data access agreement. Contact: [email protected]


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Study results articleYes Published online November 10, 2011 https://doi.org... [More Details]

Documents added automatically
SourceTitleYear of PublicationDOI
Dimensions AIResidual sleep-disordered breathing during autotitrating continuous positive airway pressure therapy2011https://doi.org/10.1183/09031936.00093811
N.B. These documents automatically identified may not have been verified by the study sponsor.