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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of continuous positive airway pressure in heart failure and obstructive sleep apnoea on left ventricular function
Scientific title
The effect of continuous positive airway pressure in heart failure and obstructive sleep apnoea on left ventricular function
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Heart failure / obstructive sleep apnoea 1387 0
Condition category
Condition code
Cardiovascular 1480 1480 0 0
Other cardiovascular diseases
Respiratory 1481 1481 0 0
Sleep apnoea

Study type
Description of intervention(s) / exposure
Non randomised parallel study. Intervention group: Continuous positive airway pressure (CPAP) device used for treating obstructive sleep apnoea to be used each sleeping period at home. This is a standard treatment device for treating obstructive sleep apnoea. It involves sleeping with a nasal or full face mask attached to the pressure machine. The pressure is individually determined for each subject via titration. Duration for both groups 6 months.
Intervention code [1] 1374 0
Treatment: Devices
Comparator / control treatment
Control Group: usual medical treatment ie continued medication for heart failure as per primary care physician instructions.
Control group

Primary outcome [1] 2052 0
Left Ventricular Ejection Fraction
Timepoint [1] 2052 0
Measured at 6 months followup after baseline
Secondary outcome [1] 3537 0
Daytime sleepiness
Timepoint [1] 3537 0
Measured at baseline and at 6 months.
Secondary outcome [2] 3538 0
Quality of life
Timepoint [2] 3538 0
Measured at baseline and at 6 months.

Key inclusion criteria
Adults with heart failure (Left ventricular ejection fraction < 45%) and Obstructive Sleep Apnoea (Apnoea/hypopnoea index > 10/hr).
Minimum age
18 Years
Maximum age
Not stated
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Renal failure, respiratory failure, pyschiatric history, alcohol dependancy.

Study design
Purpose of the study
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
Other design features
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 397 0
New Zealand
State/province [1] 397 0

Funding & Sponsors
Funding source category [1] 1619 0
Name [1] 1619 0
Wellington Medical Research Foundation
Address [1] 1619 0
Country [1] 1619 0
New Zealand
Primary sponsor type
Otago University
New Zealand
Secondary sponsor category [1] 1420 0
Name [1] 1420 0
Research Administrator, Christine Groves, Wellington School of Medicine
Address [1] 1420 0
Country [1] 1420 0
New Zealand

Ethics approval
Ethics application status
Ethics committee name [1] 3067 0
WellSleep-Wellington Ethics Committee
Ethics committee address [1] 3067 0
Ethics committee country [1] 3067 0
New Zealand
Date submitted for ethics approval [1] 3067 0
Approval date [1] 3067 0
Ethics approval number [1] 3067 0

Brief summary
The study is designed to provide evidence of whether patients with heart failure and obstructive sleep apnoea gain benefit from Continuous Positive Airway Pressure treatment not only in terms of treating Obstructive Sleep Apnoea but on heart function as well. The study hypothesis is that CPAP will have a beneficial effect on heart function as measured by an increase in left ventricular ejection fraction.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 27601 0
Address 27601 0
Country 27601 0
Phone 27601 0
Fax 27601 0
Email 27601 0
Contact person for public queries
Name 10563 0
Dr Alister Neill
Address 10563 0
Wellington School of Medicine
Po Box 7343
Country 10563 0
New Zealand
Phone 10563 0
+64 4 3855999
Fax 10563 0
Email 10563 0
Contact person for scientific queries
Name 1491 0
Dr Alister Neill
Address 1491 0
Wellington School of Medicine
Po Box 7343
Wellington South
Country 1491 0
New Zealand
Phone 1491 0
+64 4 3855999
Fax 1491 0
Email 1491 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary