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Trial registered on ANZCTR


Trial ID
ACTRN12605000271606
Ethics application status
Approved
Date submitted
31/08/2005
Date registered
2/09/2005
Date last updated
4/01/2011
Type of registration
Retrospectively registered

Titles & IDs
Public title
Obstructive Sleep Apnoea and Cardiovascular Disease
Scientific title
The effects of short term hypoxia on arterial stiffness in subjects with obstructive sleep apnoea.
Secondary ID [1] 132 0
Sydney South West Area Health Service Ethic Committee: X03-0003
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obstructive Sleep Apnoea (OSA) 358 0
Condition category
Condition code
Respiratory 420 420 0 0
Sleep apnoea

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Subjects will be exposed to short term hypoxia aiming for a target saturation of 80% while haemodynamic and ventilatory parameters are measured. They will breathe through a mouthpiece connected to special equipment which delivers different gas mixtures and enables the delivery of the hypoxic exposure. Heart rate, blood pressure, arterial stiffness ( via pulse wave analysis), and peripheral vasoconstriction (via peripheral arterial tonometry PAT) will be measured. Initially there will be a 10 minute baseline period followed by the 20 minute period of hypoxia and then a 10 minute recovery period. A proportion of subjects will then be studied after being commenced on treatment with continuous positive airway pressure (CPAP).
Intervention code [1] 317 0
None
Comparator / control treatment
Control group
Uncontrolled

Outcomes
Primary outcome [1] 482 0
Measure the effect that short term hypoxia has on the change in augmentation index (AIx, an index of arterial stiffness)
Timepoint [1] 482 0
Measured continuously during the 40 minute protocol.
Secondary outcome [1] 1039 0
Changes in heart rate
Timepoint [1] 1039 0
This will be measured continously during the 40 minute protocol.
Secondary outcome [2] 1040 0
Changes in blood pressure
Timepoint [2] 1040 0
This will be measured continously during the 40 minute protocol.
Secondary outcome [3] 1041 0
Changes in peripheral arterial tonometry
Timepoint [3] 1041 0
This will be measured continously during the 40 minute protocol.
Secondary outcome [4] 1042 0
Changes in ventilation with hypoxic exposure
Timepoint [4] 1042 0
This will be measured continously during the 40 minute protocol.

Eligibility
Key inclusion criteria
Severe OSA based on polysomnography (Respiratory Disturbance Index (RDI) 25 ).
Minimum age
Not stated
Maximum age
Not stated
Gender
Males
Can healthy volunteers participate?
No
Key exclusion criteria
History of other cardiovascular or respiratory disease including hypertension, hypercholesterolemia, ischaemic heart disease or diabetesSmoker Treatment with cardiovascular or respiratory medication.

Study design
Purpose of the study
Diagnosis
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Phase 3
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 473 0
Government body
Name [1] 473 0
National Health and Medical Research Council
Address [1] 473 0
Country [1] 473 0
Australia
Primary sponsor type
Government body
Name
NHMRC
Address
Country
Australia
Secondary sponsor category [1] 380 0
Government body
Name [1] 380 0
NHMRC
Address [1] 380 0
Country [1] 380 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 1447 0
Royal Prince Alfred Hospital
Ethics committee address [1] 1447 0
Ethics committee country [1] 1447 0
Australia
Date submitted for ethics approval [1] 1447 0
Approval date [1] 1447 0
Ethics approval number [1] 1447 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 35440 0
Address 35440 0
Country 35440 0
Phone 35440 0
Fax 35440 0
Email 35440 0
Contact person for public queries
Name 9506 0
Ms Wendy Taylor
Address 9506 0
PO Box M77
Missenden Road
Camperdown NSW 2050
Country 9506 0
Australia
Phone 9506 0
+61 2 95156578
Fax 9506 0
+61 2 95505865
Email 9506 0
wtaylor@woolcock.org.au
Contact person for scientific queries
Name 434 0
Dr Hima Vedam
Address 434 0
PO Box M77
Missenden Road
Camperdown NSW 2050
Country 434 0
Australia
Phone 434 0
+61 404072392
Fax 434 0
Email 434 0
himav@mail.med.usyd.edu.au