The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12619000027112
Ethics application status
Approved
Date submitted
22/08/2018
Date registered
11/01/2019
Date last updated
13/11/2019
Date data sharing statement initially provided
11/01/2019
Type of registration
Retrospectively registered

Titles & IDs
Public title
Assessing the health effects of six months of simulated wind farm infrasound: A community-based randomised controlled trial.
Scientific title
Assessing the health effects of six months of simulated wind farm infrasound: A community-based randomised controlled trial
Secondary ID [1] 293563 0
Australian NH&MRC Targeted Call for Research Grant Grant APP113615
Universal Trial Number (UTN)
Trial acronym
Linked study record
Concurrently we are conducting this registered trial that is sleep laboratory based and investigates short term effects of infrasound on human health. ACTRN12617000001392

Health condition
Health condition(s) or problem(s) studied:
Sleep disturbance

305796 0
Wind Turbine Syndrome 309601 0
Condition category
Condition code
Neurological 305014 305014 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will be randomised to one of two groups. One group exposed to six months continuous infrasound speaker exposure and the other group exposed to sham (no sound) speaker exposure. The key exposure of windfarm simulated infrasound at 93dB pK (test exposure) will be generated by specially manufactured speaker boxes which will be placed in each of the participants’ bedrooms and will operate continuously for the duration of the study. Microphones continuously monitor the presence and level of infrasound in the bedroom for the duration of the study.
Intervention code [1] 299808 0
Other interventions
Comparator / control treatment
No added sound (sham, negative control). Speaker boxes identical to the infrasound generating boxes used for the wind farm exposure will be placed in the participants’ bedrooms.

Control group
Placebo

Outcomes
Primary outcome [1] 304180 0
Changes in wake after sleep onset (WASO) as determined by 4 EEG channel polysomnography with the Alice PDx portable recorder, This will be defined using standard electroencephalography (EEG) based criteria. We will compare the effects of infrasound and sham.
Timepoint [1] 304180 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement. The primary timepoint will be the 6 month measurement.
Secondary outcome [1] 341146 0
Sleep latency (Time to onset of 1st sleep at night as determined by a polysomnography)
Timepoint [1] 341146 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement.
Secondary outcome [2] 350439 0
Sleep Stage Shifts (The total number of sleep stage transitions over the whole night as determined by a polysomnography)
Timepoint [2] 350439 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement.
Secondary outcome [3] 350440 0
Sleep staging (A measure of sleep architecture using the proportions of recorded sleep time that are scored as being stage 1 2 3 or REM sleep as recorded on a polysomnography)
Timepoint [3] 350440 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement.
Secondary outcome [4] 350441 0
Arousal frequency (the Arousal Index is a measure of the number or cortical arousals captured via the EEG on a polysomnography per hour of scored sleep)
Timepoint [4] 350441 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement.
Secondary outcome [5] 350442 0
Power spectral analysis for sleep microarchitecture analysis

Quantitative EEG analysis techniques will be applied to all sleep EEG signals from polysomnography recordings after identification and exclusion of artefacts. Sleep stage specific power spectra using a fast Fourier transform routine and scaling exponents from detrended fluctuation analysis will be quantified. Sleep spindle characteristics including density (no. of spindles/min of NREM), duration, and morphology (frequency, amplitude and symmetry), and dynamics of slow wave activity (SWA) across the night will also be computed. The topographical and regional distribution of sleep EEG oscillations (i.e. SWA, K-complexes and sleep spindles) will be examined to detect changes in cortical activity across key brain regions that may occur from the study interventions. EEG data will be collected using established data acquisition processes using hospital approved sleep recording systems in the sleep laboratory. Analysis of EEG data will be performed through internally developed and validated software as well as PhiTools PRANA software.
Timepoint [5] 350442 0
Single overnight polysomnography study will be measured at 3 months and 6 months after the initial baseline measurement.
Secondary outcome [6] 354322 0
Sleep parameters measured by actigraphy
Timepoint [6] 354322 0
At 6 months after the initial baseline measurement.
Secondary outcome [7] 354323 0
Neurocognitive test (n-back score and Tower of London score)
Timepoint [7] 354323 0
At 6 months after the initial baseline measurement.
Secondary outcome [8] 354324 0
Insomnia Severity Index (ISI) score (range: 0 to 28)
Timepoint [8] 354324 0
At 6 months after the initial baseline measurement.
Secondary outcome [9] 354325 0
Epworth Sleepiness Scale (ESS) score (range: 0 to 24)
Timepoint [9] 354325 0
At 6 months after the initial baseline measurement.
Secondary outcome [10] 354326 0
Noise Annoyance Visual Analog Scale (range: 0 to 10)
Timepoint [10] 354326 0
At 6 months after the initial baseline measurement.
Secondary outcome [11] 354327 0
General Health Symptoms Visual Analog Scale (range: 0 to 10)
Timepoint [11] 354327 0
At 6 months after the initial baseline measurement.
Secondary outcome [12] 354328 0
Kessler 10 (K10) score (range: 10 to 50)
Timepoint [12] 354328 0
At 6 months after the initial baseline measurement.
Secondary outcome [13] 354329 0
Depression, Anxiety and Stress Scale (DASS-21) score (range: 0 to 42 depression, anxiety and stress)
Timepoint [13] 354329 0
At 6 months after the initial baseline measurement.
Secondary outcome [14] 354330 0
Warwick Edinburgh Mental Wellbeing Scale score
(range: 14 to 70)
Timepoint [14] 354330 0
At 6 months after the initial baseline measurement.
Secondary outcome [15] 354331 0
Stress marker - Hair cortisol (ng/50mg)
Timepoint [15] 354331 0
At 6 months after the initial baseline measurement.
Secondary outcome [16] 354332 0
Anthropometric measures - Body Mass Index by portable stadiometer for the height component and by portable digital scale for the weight component
Timepoint [16] 354332 0
At 6 months after the initial baseline measurement.
Secondary outcome [17] 354333 0
Blood Pressure (mmHg) by portable digital self-inflating sphygmomanometer
Timepoint [17] 354333 0
Average of 3 measurements taken at 6 months after the initial baseline measurement.
Secondary outcome [18] 354334 0
Arterial Stiffness - Pulse Wave Velocity (m/s)
Timepoint [18] 354334 0
At 6 months after the initial baseline measurement.
Secondary outcome [19] 354335 0
Blood test - Interleukin 6 (IL-6) (pg/ml)
Timepoint [19] 354335 0
At 6 months after the initial baseline measurement.
Secondary outcome [20] 354339 0
Video Head Impulse Test
Timepoint [20] 354339 0
At 6 months after the initial baseline measurement.
Secondary outcome [21] 354340 0
Ocular Vestibular Evoked Myogenic Potentials
Timepoint [21] 354340 0
At 6 months after the initial baseline measurement.
Secondary outcome [22] 354341 0
Tandem Walking test
Timepoint [22] 354341 0
At 6 months after the initial baseline measurement.
Secondary outcome [23] 365504 0
Cervical Vestibular Evoked Myogenic Potentials
Timepoint [23] 365504 0
At 6 months after the initial baseline measurement.
Secondary outcome [24] 365505 0
Matted Romberg Test
Timepoint [24] 365505 0
At 6 months after the initial baseline measurement.
Secondary outcome [25] 365506 0
Unterburger Test
Timepoint [25] 365506 0
At 6 months after the initial baseline measurement.
Secondary outcome [26] 365509 0
Blood Test - Tumor Necrosis Factor-alpha (TNF-a) (pg/ml)
Timepoint [26] 365509 0
At 6 months after the initial baseline measurement.
Secondary outcome [27] 365510 0
Blood Test - HbA1c – NGSP (%) IFCC (mmol/mol)
Timepoint [27] 365510 0
At 6 months after the initial baseline measurement.
Secondary outcome [28] 365511 0
Blood Test - Highly sensitive C reactive protein (hs-CRP) (mg/L)
Timepoint [28] 365511 0
At 6 months after the initial baseline measurement.

Eligibility
Key inclusion criteria
1. Aged 18 or above
2. Noise sensitive individuals -defined as Weinstein’s Noise Sensitivity Scale (WNS) Score >58 (which was the median score in a reported study)
3. Normal hearing based on phone questionnaire
4. Regular sleep of minimum 5.5 hours / 24 hours for 7 days as demonstrated by 1 week of actigraphy
5. Fluent in English, to be able to answer computerised questionnaires and undergo neurocognitive assessments in English

Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Rotating shift worker
2. Planning to be away from home for more than a month during the study period
3. Major psychiatric disorders
4. Use of any hypnotic medications or other medications that interfere with sleep within the last month
5. Anyone in the household pregnant or breastfeeding or planning to during the study period
6. Children younger than 5 years of age living or regularly spending time in the home.


Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Secure randomisation will be achieved through Research Tools(TM) by entering secure participant data in order to access a unique participant randomisation number. The unique participant number will be assigned in ascending chronological order. Screening of suitable participants will be undertaken in three phases. The first phase will be done over the phone to check if the participant has normal hearing and does not wear a hearing aid. The second phase will be conducted via an online screening questionnaire. The third phase will combine a non- invasive technique (wrist actigraphy and sleep diary) for the at-home measurement of normal sleep/wake cycles.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Participants will be assigned the type of exposure (infrasound speaker or sham speaker) in a random order. A statistician who assists the Data Safety Monitoring Board (DSMB) and who will never meet any participant or play role in selection or testing of participants has computer generate the randomisation list in blocks of 12, with 12 blocks of 12 = 144 randomisation numbers..
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Expectations on the part of participants and investigators may influence the effect of the exposure (infrasound) and, more particularly, may influence the measurement of those effects, especially the subjective (self-reported) outcomes. To avoid the potential for this measurement bias, it is important that both participants and the investigators who are measuring outcomes are blinded to the intervention group. Fortunately, as infrasound is, by definition, inaudible, this is readily achieved by the use of a sham device that appears the same as the infrasound device, but which does not produce any sound. Only the unblinded acoustic engineer will have knowledge of the exposure and they will never meet a participant.

Phase
Not Applicable
Type of endpoint/s
Safety
Statistical methods / analysis
Generalised linear mixed models will be utilised for statistical analysis. WASO will be the dependent variable in the primary analysis. All other outcomes will be tested separately as dependent variables. Exposure (infrasound vs sham) will be the main fixed effect. As multiple outcome measures will be made (at baseline and at 3 & 6 month follow-ups) a “time” fixed effect will also be included and exposure-by-time interactions will be tested. The differences specifically at the 6 month time period will be the primary endpoint. In sub-analyses we will also test whether changes in outcomes are influenced by whether people thought windfarms have health effects (expectancy) to establish whether this attribute modifies the propensity to experience WTS symptoms with exposure.

Recruitment
Recruitment status
Stopped early
Data analysis
No data analysis planned
Reason for early stopping/withdrawal
Participant recruitment difficulties
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)
NSW
Recruitment postcode(s) [1] 18260 0
2570 - Camden
Recruitment postcode(s) [2] 18261 0
2571 - Picton
Recruitment postcode(s) [3] 22066 0
2904 - Macarthur

Funding & Sponsors
Funding source category [1] 298177 0
Government body
Name [1] 298177 0
NHMRC
Country [1] 298177 0
Australia
Primary sponsor type
Other
Name
Woolcock Institute of Medical Research
Address
431 Glebe Point Road
Glebe 2037
NSW
Country
Australia
Secondary sponsor category [1] 297275 0
None
Name [1] 297275 0
Address [1] 297275 0
Country [1] 297275 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299192 0
Sydney Local Health District Ethics Review Committee (Royal Prince Alfred Hospital Zone)
Ethics committee address [1] 299192 0
Research Development Office
Royal Prince Alfred Hospital
Missenden Road
Camperdown NSW 2050
Ethics committee country [1] 299192 0
Australia
Date submitted for ethics approval [1] 299192 0
25/08/2017
Approval date [1] 299192 0
06/09/2017
Ethics approval number [1] 299192 0
X17-0235 and HREC 17/RPAH/351

Summary
Brief summary
The study hypothesis is that exposure to infrasound, compared with the sham exposure, is associated with impaired sleep quality.

We will randomly allocate participants to one of two groups. One group will receive speakers that generate wind farm simulated infrasound and the other group will receive speakers that generate no sound (sham). The speakers will be installed in the bedroom, will operate continuously and remain in place for 6 months.

In addition, to impairment of sleep quality we will assess whether six months exposure to wind farm simulated infrasound is associated with other health effects such as annoyance, impaired neurobehavioural and neurocognitive performance, impaired vestibular function, increased arterial stiffness, increased blood pressure, mood, anxiety and stress. Secondly, to investigate whether experiencing an excess of symptoms that have been attributed to Wind Turbine Syndrome is related to baseline levels of stress and anxiety.
Trial website
https://www.windfarmstudy.com
Trial related presentations / publications
Public notes
Attachments [1] 2256 2256 0 0
Attachments [3] 2944 2944 0 0
/AnzctrAttachments/374136-2675_005.pdf (Ethics approval)
Attachments [4] 2945 2945 0 0

Contacts
Principal investigator
Name 79602 0
Prof Guy Marks
Address 79602 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe
NSW 2037
Country 79602 0
Australia
Phone 79602 0
+61 2 9114 4066
Fax 79602 0
+61 2 9114 0011
Email 79602 0
Contact person for public queries
Name 79603 0
Dr Brett Toelle
Address 79603 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe
NSW 2037
Country 79603 0
Australia
Phone 79603 0
+61 2 9114 4062
Fax 79603 0
+61 2 9114 0011
Email 79603 0
Contact person for scientific queries
Name 79604 0
Dr Brett Toelle
Address 79604 0
Woolcock Institute of Medical Research
431 Glebe Point Road
Glebe
NSW 2037
Country 79604 0
Australia
Phone 79604 0
+61 2 9114 4062
Fax 79604 0
+61 2 9114 0011
Email 79604 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Deidentified individual record data
When will data be available (start and end dates)?
Data will be available from date of publication of the main report and for 10 years from the date of publication.
Available to whom?
Researchers who provide a scientifically valid and ethically approved protocol
Available for what types of analyses?
Available for analyses contained within an ethically approved protocol
How or where can data be obtained?
Data will be provided to the researcher directly by the Principal Investigator subject to receipt of the ethics approval and the ethically approved protocol.


What supporting documents are/will be available?

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.