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Trial registered on ANZCTR

Trial ID
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
A randomized controlled trial of the effect of substantial weight loss on obstructive sleep apnoea as measured by the apnoea/hypopnoea index.
Scientific title
A randomized controlled trial of the effect of substantial weight loss on obstructive sleep apnoea as measured by the apnoea/hypopnoea index.
Secondary ID [1] 253243 0
OSA and weight loss
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obstructive sleep apnoea 256 0
Condition category
Condition code
Respiratory 288 288 0 0
Sleep apnoea

Study type
Description of intervention(s) / exposure
Sixty patients with severe obstructive sleep apnoea (OSA), defined as an apnoea/hypopnoea index greater than 20, will be randomized to best medical care or to Lap-Band placement plus best medical care.
Intervention code [1] 175 0
Treatment: Surgery
Comparator / control treatment
Best medical care plus active lifestyle program
Control group

Primary outcome [1] 335 0
Change in apnoea/hypopnoea index as measured by diagnostic polysomnography
Timepoint [1] 335 0
At 2-years from randomization.
Secondary outcome [1] 760 0
Polysomnography and Sleep: Change in CPAP pressure and requirements
Timepoint [1] 760 0
At 2-years
Secondary outcome [2] 761 0
Differences in other measures derived from the diagnostic polysomnograph including: arousal index, proportion of REM sleep, stage 111 and 1V, lowest oxygen saturation and longest apnoea.
Timepoint [2] 761 0
At 2-years
Secondary outcome [3] 762 0
Biochemical: changes in fasting blood glucose, insulin and C-peptide (insulin resistance and beta cell function using homeostatic model assessment), fasting tri-glycerides, total cholesterol, HDL-cholesterol, ALT, AST, microalbuminuria, and CRP.
Timepoint [3] 762 0
Changes in 2-years
Secondary outcome [4] 763 0
Clinical: changes in blood pressure, differences in medication required in managing sleep apnoea, diabetes, dyslipidaemia, hypertension and other comorbidity of OSA or obesity, change in associated obesity comorbidity, ovulatory dysfunction, diabetes, enzyme markers of liver function, asthma and gastroesophageal reflux, weight change as measured by change of weight (kg), BMI, percentage excess weight loss and the percentage of excess BMI lost, (At 2-years the incidence of major adverse events would not be expected to be high. However, any differences in mortality, major vascular morbidity, major complications, and the development of clear evidence of serious obesity related disease, will constitute major adverse events and be reported. The study has not been powered for the detection in differences of major adverse events of safety.)
Timepoint [4] 763 0
Changes at 2-years
Secondary outcome [5] 764 0
Functional Status: Epworth Sleepiness Score, Berlin questionnaire, Pittsburgh sleep quality index, SF36, Multi-dimensional Body-Self Relations Questionnaire, Beck Depression Inventory, employment status.
Timepoint [5] 764 0
At 24 months
Secondary outcome [6] 765 0
Complications: any complications of the Lap-Band including peri-operative morbidity or mortality or late complications including band obstruction, intolerance, gastric slippage or pouch development, erosion, access port leaks, infection and tubing problems, any complication or lack of tolerance of therapy for OSA and medical therapy used in the treatment of OSA, obesity or their related comorbidities.
Timepoint [6] 765 0
At 24 months
Secondary outcome [7] 766 0
Costs of all therapy required for management of OSA or obesity related conditions will be reported, including hospital, medical, and allied professional costs and the costs of CPAP therapy, pharmaceuticals and prescribed nutrient supplements.
Timepoint [7] 766 0
At 24 months

Key inclusion criteria
Have a body mass index between 32 and 50kg/m2, able to indicate several genuine attempts top lose significant weight, be recently diagnosed (6-months) with moderate to severe symptomatic obstructive sleep apnoea (AHI>20/hr) and have been advised to use nasal CPAP therapy for treatment (Satisfactory implementation or compliance with CPAP therapy would not be required as an entry criterion), be willing to be randomized into one of the two treatment programs and be able to understand the options, study requirements, and to comply with the requirements of both programs.
Minimum age
18 Years
Maximum age
60 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Failure to have made at least 3 significant attempts at weight loss, , history of previous abdominal surgery which would potentially preclude laparascopic placement of the band , obesity hypoventilation syndrome requiring BIPAP therapy (i.e. raised CO2 levels) or contraindication to a diagnostic sleep study, history of surgery to the airway for snoring or OSA, finding of a significant upper airway deformity or obstruction that was not obesity related (e.g. enlarged tonsils or nasal obstruction), medical problems which contra-indicate the application of either arm of the study including acute myocardial infarction within the past 6 months, dementia, active psychosis, concurrent experimental drug use, autoimmune disease, pregnancy, lactation, illicit drug use, excessive alcohol intake, use of drugs known to affect body composition, cytotoxic drugs, internal malignancy or major organ failure), sex if gender stratification is necessary due to numbers randomized . Gender stratification may be necessary as approximately equal numbers of men and women will be admitted to the study. If 26 of one gender have been randomly allocated the remaining subjects will be of the opposite gender.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Intervention recorded and stored in numbered, sealed opaque envelopes organized and maintained by staff member not involved in patient care or scheduling and opened in sequence as randomized.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Subjects will be block randomized into 3 unequal blocks. Each block will contain equal numbers in both treatment arms. The sequence within blocks will be determined by the staff member in control of concealment drawing the allocation out of a hat and the number in each blocking group will be known only to this staff member.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Active, not recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 344 0
Government body
Name [1] 344 0
Address [1] 344 0
Level 5, 20 Allara Street
Canberra ACT 2601
Country [1] 344 0
Funding source category [2] 345 0
Commercial sector/Industry
Name [2] 345 0
Inamed Health
Address [2] 345 0
5540 Ekwill Street
Santa Barbara CA 93111
Country [2] 345 0
United States of America
Funding source category [3] 2572 0
Name [3] 2572 0
Affinity Health
Address [3] 2572 0
The Avenue Hospital
The Avenue, Windsor Vic 3181
Country [3] 2572 0
Funding source category [4] 2573 0
Commercial sector/Industry
Name [4] 2573 0
Applied Medical
Address [4] 2573 0
1/32 Windorah Street
Stafford City
QLD 4053
Country [4] 2573 0
Primary sponsor type
Monash University School of Primary Health Care
Monash University
School of Primary Health Care
Building 1, 270 Ferntree Gully Road
Notting Hill Vic 3168
Secondary sponsor category [1] 272 0
Name [1] 272 0
Address [1] 272 0
Country [1] 272 0

Ethics approval
Ethics application status
Ethics committee name [1] 1291 0
Alfred Hospital
Ethics committee address [1] 1291 0
Commercial Road Melbourne VIC 3004
Ethics committee country [1] 1291 0
Date submitted for ethics approval [1] 1291 0
Approval date [1] 1291 0
Ethics approval number [1] 1291 0
Ethics committee name [2] 1292 0
The Avenue Hospital
Ethics committee address [2] 1292 0
The Avenue, Windsor Vic 3181
Ethics committee country [2] 1292 0
Date submitted for ethics approval [2] 1292 0
Approval date [2] 1292 0
Ethics approval number [2] 1292 0
Trial 058
Ethics committee name [3] 4492 0
Monash University SCERH
Ethics committee address [3] 4492 0
Building 3D, Clayton Campus Wellington Road
Clayton VIC
Ethics committee country [3] 4492 0
Date submitted for ethics approval [3] 4492 0
Approval date [3] 4492 0
Ethics approval number [3] 4492 0

Brief summary
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 35147 0
Address 35147 0
Country 35147 0
Phone 35147 0
Fax 35147 0
Email 35147 0
Contact person for public queries
Name 9364 0
Mr Tony Xu
Address 9364 0
School of Primary Health Care
Building 1, 270 Ferntree Gully Road
Notting Hill 3168
Country 9364 0
Phone 9364 0
+61 3 8575 2287
Fax 9364 0
+61 3 8575 2233
Email 9364 0
Contact person for scientific queries
Name 292 0
Associate Professor John Dixon
Address 292 0
School of Primary Health Care
Building 1, 270 Ferntree Gully Road
Notting Hill 3168
Country 292 0
Phone 292 0
+61 3 9902 4511
Fax 292 0
+61 3 8575 2233
Email 292 0