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Trial registered on ANZCTR


Registration number
ACTRN12610000680066
Ethics application status
Approved
Date submitted
18/08/2010
Date registered
18/08/2010
Date last updated
25/02/2014
Type of registration
Prospectively registered

Titles & IDs
Public title
An investigation of affective and neuropsychological functioning and driving simulator performance in shift workers and patients with obstructive sleep apnoea
Scientific title
A comparison of rotating shift workers and untreated obstructive sleep apnoea sufferers to a matched control group on driving simulator performance, and affective and neuropsychological functioning.
Secondary ID [1] 252478 0
nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
circadian rhythm disruption 257977 0
untreated obstructive sleep apnoea 257979 0
Condition category
Condition code
Public Health 258141 258141 0 0
Health promotion/education
Respiratory 258142 258142 0 0
Sleep apnoea

Intervention/exposure
Study type
Observational
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
One afternoon of testing involving 1) neuropsychological assessments: Logical Memory, Trails A & B, Digit Span, Stroop; 2) mood evaluation: Beck Depression Inventory, Profile of Mood States, State-Trait Anxiety Inventory; 3) driving simulation task; and 4) reaction time and sustained attention tasks: Psychomotor Vigilance Task (PVT), Oxford Sleep Resistance task (Osler-2). Testing will last for approximately four hours, commencing at 13:00.

The order of testing will be the same for every participant: Logical Memory, Trails A & B, Digit Span, Stroop, Beck Depression Inventory, Profile of Mood States, State-Trait Anxiety Inventory, Logical Memory Recall, first Osler-2, driving simulation, PVT, second Osler-2
Intervention code [1] 257030 0
Not applicable
Comparator / control treatment
The three groups will be compared across all tasks: rotating shift workers, untreated obstructive sleep apnoea sufferers, and a matched control group.
Control group
Active

Outcomes
Primary outcome [1] 259004 0
Driving simulation performance: 30 minutes on the AusEd driving simulator task - measured by: average steering deviation from participant's median lane position (cm), average speed deviation outside the 60-80km/h speed zone, median reaction time for braking after sudden appearance of trucks, & number of crashes of all types.
Timepoint [1] 259004 0
In the battery of tasks following the first Osler-2 task and prior to the Psychomotor Vigilance Task
Primary outcome [2] 259005 0
Neuropsychological assessments: working memory measured by Logical Memory and Digit Span; cognitive flexibility measured by Trails A & B; response inhibition measured by Stroop; sustained attention measured by the Osler-2; and reaction time measured by the PVT.
Timepoint [2] 259005 0
Logical Memory, Trails A & B, Digit Span, and Stroop will be administered at the beginning of the afternoon. Logical Memory Recall will follow on from the evaluation of mood. The Osler-2 will be presented twice: following the Logical Memory Recall and following the PVT.
Primary outcome [3] 259006 0
Mood evaluation: mood will be assessed using the Beck Depression Inventory, the Profile of Mood States, and the State-Trait Anxiety Inventory.
Timepoint [3] 259006 0
Questionnaires will be given after the neuropsychological assessment battery of Logical Memory, Trails A & B, Digit Span, and Stroop, and prior to the Logical Memory Recall.
Secondary outcome [1] 265236 0
Ocular measures of drowsiness (via Optalert system)
Timepoint [1] 265236 0
Assessed during the performance of driving simulation, PVT and Osler-2 tasks.
Secondary outcome [2] 265237 0
Karolinska Sleepiness Scale (KSS) scores
Timepoint [2] 265237 0
Assessed prior to and upon completion of each of the driving simulation, PVT and Osler-2 tasks.
Secondary outcome [3] 265238 0
Stop Driving Questionnaire score
Timepoint [3] 265238 0
Administered upon completion of the driving simulation task
Secondary outcome [4] 265239 0
Sleepiness Symptoms Questionnaire
Timepoint [4] 265239 0
Administered upon completion of the driving simulation task.
Secondary outcome [5] 265240 0
Driving History Questionnaire
Timepoint [5] 265240 0
Administered upon completion of the testing session.

Eligibility
Key inclusion criteria
1) Current driver licence for all participants
2) Obstructive sleep apnoea participants: moderate to severe obstructive sleep apnoea (apnoea hypopnoea index > 20/hr and Epworth Sleepiness Scale score >8).
3) Shiftwork participants: at least 3 months of rotating shifts
Minimum age
18 Years
Maximum age
65 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1) Chronic neurological illness or significant medical co-morbidity
2) Chronic psychiatric illness
3) Visual acuity problems not correctable with glasses
4) Regular use of sedating medication
5) Inability to give informed consent
6) Inability to speak or write English.

Shiftworker participants only: a Multivariable Apnoea Prediction Score (>0.5).
Control participants only: a Multivariable Apnoea Prediction Score (>0.5) and/or Epworth Sleepiness Scale score (>10).

Study design
Purpose
Duration
Selection
Timing
Statistical methods / analysis

Recruitment
Recruitment status
Completed
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] 257483 0
Government body
Name [1] 257483 0
VicRoads
Address [1] 257483 0
60 Denmark Street Kew, Victoria 3101
Country [1] 257483 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Institute for Breathing and Sleep
Address
Austin Hospital PO Box 5555 Heidelberg, Victoria 3084
Country
Australia
Secondary sponsor category [1] 256719 0
None
Name [1] 256719 0
Address [1] 256719 0
Country [1] 256719 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 259511 0
Austin Health Human Research Ethics Committee
Ethics committee address [1] 259511 0
Research Ethics Unit Austin Hospital PO Box 5555 Heidelberg, Victoria 3084
Ethics committee country [1] 259511 0
Australia
Date submitted for ethics approval [1] 259511 0
18/12/2009
Approval date [1] 259511 0
03/03/2010
Ethics approval number [1] 259511 0
H2010/03831

Summary
Brief summary
This study will investigate the mood, cognitive and performance impairments in obstructive sleep apnoea patients and shift workers compared to a control group. A series of questionnaires and tasks that measure driving ability, attention, reaction time, and higher thinking functions will be undertaken. The study hopes to determine whether different patterns of neuropsychological function and sleepiness predict simulated driving performance and accident risk.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 30975 0
Dr Mark Howard
Address 30975 0
Institute of Breathing and Sleep Bowen Centre Dept. Respiratory and Sleep Medicine Austin Hospital PO Box 5555 Heidelberg Victoria 3084
Country 30975 0
Australia
Phone 30975 0
+61 3 9496 3528
Fax 30975 0
Email 30975 0
mark.howard@austin.org.au
Contact person for public queries
Name 14222 0
Miss Justine Westlake
Address 14222 0
Institute of Breathing and Sleep
Bowen Centre
Dept. Respiratory and Sleep Medicine
Austin Hospital
PO Box 5555
Heidelberg Victoria 3084
Country 14222 0
Australia
Phone 14222 0
+61 3 9496 3528
Fax 14222 0
Email 14222 0
justine.westlake@austin.org.au
Contact person for scientific queries
Name 5150 0
Miss Justine Westlake
Address 5150 0
Institute of Breathing and Sleep
Bowen Centre
Dept. Respiratory and Sleep Medicine
Austin Hospital
PO Box 5555
Heidelberg Victoria 3084
Country 5150 0
Australia
Phone 5150 0
+61 3 9496 3528
Fax 5150 0
Email 5150 0
justine.westlake@austin.org.au

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