Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621000395831
Ethics application status
Approved
Date submitted
19/01/2021
Date registered
9/04/2021
Date last updated
9/04/2021
Date data sharing statement initially provided
9/04/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
Oral Appliance Therapy (OAT) for Obstructive Sleep Apnoea (OSA) on cardiovascular risk markers
Scientific title
A pre-post study of effect of Oral Appliance Therapy for Obstructive Sleep Apnoea on Endothelial Function, Arterial Stiffness, and Autonomic Function
Secondary ID [1] 303186 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obstructive sleep apnoea 320336 0
Condition category
Condition code
Respiratory 318254 318254 0 0
Sleep apnoea

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Oral Appliance Therapy (OAT) is a recommended therapy for OSA. The therapy entails wearing a customised dental device during sleep. The device is digitally milled from dental impressions obtained by a dentist, and hence each device is customised to an individual's dentition. All participants will receive OAT implemented by a dentist with experience in OAT according to standard clinical protocols and monitoring.
Participants will attend an initial dental visit to obtain impressions to manufacture the device (~1 hour). The device will be fitted by the dentist at a second visit (~40 minutes).
Participants will be instructed to wear the device whenever they sleep for the duration of the trial (6 months).
Participants will have follow-up dental visits at mid-point (3 months) and end of the trial (6 months, ~30 minutes per visit). Participants will have opportunity for additional dental visits on an ad hoc basis if there are any issues which require assessment by the dentist, such as issues with device fit.
All devices are fitted with an objective compliance monitor, a small temperature-sensing chip which is embedded within the appliance material. Compliance data will be downloaded from the chip using a reading station at study visits.
Participants will have had a diagnostic sleep study performed for clinical purposes before entering the study. During the sleep study multiple physiological signals are monitored including respiration to assess for obstructive breathing events. At the end of the study (6 months), participants will have a repeat overnight sleep study (1 x 8 hours) in a clinical sleep laboratory, administered by the sleep laboratory staff and under their sleep specialist. The participant will use OAT for the duration of the study.
Intervention code [1] 319506 0
Treatment: Devices
Comparator / control treatment
No control group (all participants receive oral appliance therapy)
Control group
Uncontrolled

Outcomes
Primary outcome [1] 326235 0
change in endothelial function (flow mediated dilation of brachial artery by ultrasound)
Timepoint [1] 326235 0
6 months post intervention commencement
Secondary outcome [1] 390656 0
change in 24-hour blood pressure (peripheral and central measure by Oscar 2 ambulatory blood pressure monitor with SphygmoCor)
Timepoint [1] 390656 0
3 months post intervention commencement
Secondary outcome [2] 390657 0
change in arterial stiffness (pulse wave velocity)
Timepoint [2] 390657 0
3 and 6 months post intervention commencement
Secondary outcome [3] 390658 0
change in autonomic function (heart rate variability, ECG)
Timepoint [3] 390658 0
3 and 6 months post intervention commencement
Secondary outcome [4] 390659 0
change in autonomic function (blood pressure variability, Human Non-Invasive Blood Pressure System, NIBP)
Timepoint [4] 390659 0
3 and 6 months post intervention commencement
Secondary outcome [5] 390660 0
change in autonomic function (baroreceptor reflex function, Human Non-Invasive Blood Pressure System, NIBP)
Timepoint [5] 390660 0
3 and 6 months post intervention commencement
Secondary outcome [6] 390661 0
Adherence to therapy (data download from sensor chip in appliance)
Timepoint [6] 390661 0
daily usage over 6 month intervention period
Secondary outcome [7] 390662 0
Oral appliance therapy efficacy: change in sleep apnea events as assessed by overnight polysomnography
Timepoint [7] 390662 0
6 months post intervention commencement
Secondary outcome [8] 390663 0
change in subjective daytime sleepiness (Epworth Sleepiness Score)
Timepoint [8] 390663 0
3 and 6 months post intervention commencement
Secondary outcome [9] 390664 0
change in health-related quality of life (SF-36 questionnaire)
Timepoint [9] 390664 0
3 and 6 months post intervention commencement
Secondary outcome [10] 390665 0
change in disease-related quality of life (Functional Outcomes of Sleep Questionnaire)
Timepoint [10] 390665 0
3 and 6 months post intervention commencement
Secondary outcome [11] 390667 0
Oral appliance therapy efficacy: change in oxygen saturation assessed by home oximetry
Timepoint [11] 390667 0
6 months post intervention commencement

Eligibility
Key inclusion criteria
Obstructive Sleep Apnoea (with ODI(4%) > 10 events/hour)
BMI < 35 kgm2
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Use of any OSA therapy in the prior 3 months
Contra-indications to OAT (as determined by dentist e.g. periodontal disease, insufficient number of teeth to retain the device)
Women who are lactating or pregnant
Established cardio- or cerebro-vascular disease (E.g. stroke, coronary heart disease, heart failure, cardiomyopathy, congenital heart disease)
Central Sleep Apnoea (>10% central events)
Co-existing sleep disorder of lung disease (e.g. COPD)
Inability to provide informed consent

Study design
Purpose of the study
Treatment
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
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Changes in cardiovascular measurements from baseline to post treatment (3 and 6 months) will be assessed using factorial ANOVA. Subgroup analysis of those with and without baseline cardiovascular risk factors (hypertension, high Framingham risk score) will be made. Relationships between treatment efficacy and usage and changes in outcome variables will be assessed using correlation and regression analyses.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
19/01/2021
Date of last participant enrolment
Anticipated
31/12/2021
Actual
Date of last data collection
Anticipated
15/07/2022
Actual
Sample size
Target
105
Accrual to date
2
Final
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment hospital [1] 18456 0
Royal North Shore Hospital - St Leonards
Recruitment hospital [2] 18457 0
Royal Prince Alfred Hospital - Camperdown
Recruitment postcode(s) [1] 32566 0
2065 - St Leonards
Recruitment postcode(s) [2] 32567 0
2050 - Camperdown

Funding & Sponsors
Funding source category [1] 307592 0
Charities/Societies/Foundations
Name [1] 307592 0
Rebecca L Cooper Medical Foundation
Country [1] 307592 0
Australia
Primary sponsor type
Government body
Name
Northern Sydney Local Health District
Address
Douglas Building, Level 5 Reserve Rd, St Leonards NSW 2065
Country
Australia
Secondary sponsor category [1] 308283 0
None
Name [1] 308283 0
Address [1] 308283 0
Country [1] 308283 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 307647 0
Northern Sydney Local Health District
Ethics committee address [1] 307647 0
Douglas Building, Level 5 Reserve Rd, St Leonards NSW 2065
Ethics committee country [1] 307647 0
Australia
Date submitted for ethics approval [1] 307647 0
Approval date [1] 307647 0
23/12/2020
Ethics approval number [1] 307647 0

Summary
Brief summary
The purpose of this pre-post comparison study is to provide preliminary evidence for any effect of Oral Appliance Therapy (OAT) for Obstructive Sleep Apnoea (OSA) on a range of intermediary cardiovascular risk markers in sleep clinic patients with OSA.
Intermediary cardiovascular risk markers (peripheral and central blood pressure, arterial stiffness, endothelial function, autonomic function, and blood biomarkers) will be assessed at 3 and 6 months post OAT implementation. Efficacy of OAT in controlling OSA at the end of the study and adherence to OAT over the study period will be assessed via usage data downloaded from embedded adherence chip. Analysis will be performed to assess the influence of baseline cardiovascular risk status (hypertension, Framingham risk score) and treatment effectiveness (efficacy and usage) on changes in cardiovascular risk markers over the treatment period.
The recruitment target (including allowance for drop outs) will be 105 participants. This is to ensure sufficient complete responders to OAT are recruited in the sample. There are known variations in OAT efficacy. Previous research suggests that <40% of OSA patients are complete responders to treatment, 30% have minimal clinical response and the remainder have some clinical benefit. We aim to have a minimum of 30 complete responders in the sample. Data from this observational study will be used to inform future trials of OSA therapy for cardiovascular disease prevention.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 107994 0
Dr Kate Sutherland
Address 107994 0
Dept of Respiratory and Sleep Medicine
Royal North Shore Hospital
Pacific Highway
St Leonards NSW 2065
Australia
Country 107994 0
Australia
Phone 107994 0
+61 2 9463 2924
Fax 107994 0
Email 107994 0
[email protected]
Contact person for public queries
Name 107995 0
Dr Kate Sutherland
Address 107995 0
Dept of Respiratory and Sleep Medicine
Royal North Shore Hospital
Pacific Highway
St Leonards NSW 2065
Australia
Country 107995 0
Australia
Phone 107995 0
+61 2 9463 2924
Fax 107995 0
Email 107995 0
[email protected]
Contact person for scientific queries
Name 107996 0
Dr Kate Sutherland
Address 107996 0
Dept of Respiratory and Sleep Medicine
Royal North Shore Hospital
Pacific Highway
St Leonards NSW 2065
Australia
Country 107996 0
Australia
Phone 107996 0
+61 2 9463 2924
Fax 107996 0
Email 107996 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


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
No additional documents have been identified.