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Trial registered on ANZCTR


Registration number
ACTRN12619000287134
Ethics application status
Approved
Date submitted
22/02/2019
Date registered
26/02/2019
Date last updated
4/02/2020
Date data sharing statement initially provided
26/02/2019
Date results information initially provided
4/02/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Using impulse oscillometry, multiple-breath nitrogen washout and exhaled nitric oxide together to assess asthma inflammation
Scientific title
Using impulse oscillometry, multiple-breath nitrogen washout and exhaled nitric oxide before and after salbutamol inhalation to determine the site and degree of airways inflammation in patients with asthma
Secondary ID [1] 297495 0
None
Universal Trial Number (UTN)
U1111-1223-1286
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 311683 0
Condition category
Condition code
Respiratory 310312 310312 0 0
Asthma

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
One dose of inhaled salbutamol (600mcg) given by research staff via metered-dose inhaler (with spacer) over 10 minutes at one study visit.
Intervention code [1] 313735 0
Treatment: Drugs
Intervention code [2] 313759 0
Diagnosis / Prognosis
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 319199 0
Change in exhaled nitric oxide measured by exhaled nitric oxide analyser
Timepoint [1] 319199 0
Change from baseline to 30 min post dosing.
Secondary outcome [1] 367247 0
Change in area of reactance measured by impulse oscillometry.
Timepoint [1] 367247 0
Change from baseline to 30 min post dosing.
Secondary outcome [2] 367248 0
Change in lung clearance index measured by multiple breath nitrogen washout.
Timepoint [2] 367248 0
Change from baseline to 30 min post dosing.
Secondary outcome [3] 367249 0
Change in Scond (index of ventilation heterogeneity in the conducting airways) measured by multiple breath nitrogen washout.
Timepoint [3] 367249 0
Change from baseline to 30 min post dosing.
Secondary outcome [4] 367250 0
Change in Sacin (index of ventilation heterogeneity in the acinar airways) measured by multiple breath nitrogen washout.
Timepoint [4] 367250 0
Change from baseline to 30 min post dosing.
Secondary outcome [5] 367252 0
Change in forced vital capacity measured by spirometry.
Timepoint [5] 367252 0
Change from baseline to 30 min post dosing.
Secondary outcome [6] 367254 0
Change in R5-R20 measured by impulse oscillometry.
Timepoint [6] 367254 0
Change from baseline to 30 min post dosing.

Eligibility
Key inclusion criteria
Physician-diagnosed asthma requiring a minimum of treatment with regular inhaled corticosteroid.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Diagnosis of COPD, bronchiectasis, lung cancer.
Other co-morbidity likely to affect study participation.
Current smoker (any cigarette smoking within past two months).
Previous ICU admission for acute asthma.

Study design
Purpose of the study
Diagnosis
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Not applicable
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Not applicable
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Phase 4
Type of endpoint(s)
Efficacy
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 outside Australia
Country [1] 21300 0
New Zealand
State/province [1] 21300 0
Otago

Funding & Sponsors
Funding source category [1] 302058 0
University
Name [1] 302058 0
University of Otago
Address [1] 302058 0
University of Otago
362 Leith Street
Dunedin
New Zealand
9054
Country [1] 302058 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
University of Otago
362 Leith Street
Dunedin
New Zealand
9054
Country
New Zealand
Secondary sponsor category [1] 301869 0
None
Name [1] 301869 0
None
Address [1] 301869 0
None
Country [1] 301869 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 302740 0
Southern Health and Disability Ethics Committee
Ethics committee address [1] 302740 0
Health and Disability Ethics Committees
Ministry of Health
133 Molesworth Street
PO Box 5013
Wellington
6011
Ethics committee country [1] 302740 0
New Zealand
Date submitted for ethics approval [1] 302740 0
22/11/2018
Approval date [1] 302740 0
20/12/2018
Ethics approval number [1] 302740 0
18/STH/248

Summary
Brief summary
It has been argued that, because of the complex relationship between FENO and airway calibre, FENO should not be measured alone but should instead be integrated into an ‘inflammometer’ that comprises FENO measurement and physiological measurement of airways obstruction. Unfortunately, measures of small airways obstruction are not routinely used in clinical practice and this region of the lung has been described as the ‘silent zone’ as a consequence.

Impulse oscillometry and multiple breath nitrogen washout are physiological tests that can measure variables related to small airways obstruction in a research setting and they have become more reliable and user-friendly in recent years. We intend to explore the relationship between FENO and measures of small airways obstruction in patients with asthma. In particular, the relationship between FENO and measures related to small airways obstruction using impulse oscillometry has not previously been examined. This is important because, like FENO, impulse oscillometry is a simple, easy test for patients. If we could determine a relationship between FENO and measures obtained from impulse oscillometry, it might ultimately be possible to integrate the two into an ‘inflammometer’ that could be used clinically.

In this study, we will test the hypothesis that, in the presence of a stable airway inflammatory state, there is a relationship between baseline physiological measures of small airways obstruction and the change in FENO on subsequent bronchodilation with inhaled ß2-agonist.

We will recruit 40 participants with physician-diagnosed asthma. They will be asked to withhold short-acting inhaled asthma treatment for 6 hours and long-acting inhaled asthma treatment for 12-24 hours prior to a single visit to the Otago Respiratory Research Unit. At that visit, we will obtain informed consent, collect demographic data from participants and they will complete an asthma control questionnaire. Then impulse oscillometry, FENO measurement, multiple breath nitrogen washout and spirometry will be undertaken (1) at baseline and (2) after inhaled ß2-agonist therapy (bronchodilation).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 91230 0
Dr Jack Dummer
Address 91230 0
Department of Medicine
Dunedin School of Medicine
University of Otago
PO Box 56
Dunedin 9054
Country 91230 0
New Zealand
Phone 91230 0
+64 34709362
Fax 91230 0
Email 91230 0
jack.dummer@otago.ac.nz
Contact person for public queries
Name 91231 0
Dr Jack Dummer
Address 91231 0
Department of Medicine
Dunedin School of Medicine
University of Otago
PO Box 56
Dunedin 9054
Country 91231 0
New Zealand
Phone 91231 0
+64 34709362
Fax 91231 0
Email 91231 0
jack.dummer@otago.ac.nz
Contact person for scientific queries
Name 91232 0
Dr Jack Dummer
Address 91232 0
Department of Medicine
Dunedin School of Medicine
University of Otago
PO Box 56
Dunedin 9054
Country 91232 0
New Zealand
Phone 91232 0
+64 34709362
Fax 91232 0
Email 91232 0
jack.dummer@otago.ac.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
If de-identified participant data is requested for publication we will make this available. If it is requested by a 3rd party we will give this consideration.
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
No
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary