Citric acid cough challenge validation

ISRCTN	ISRCTN98385033
DOI	https://doi.org/10.1186/ISRCTN98385033
Secondary identifying numbers	AcadMed CTU04/05

Submission date: 05/06/2009
Registration date: 18/09/2009
Last edited: 25/09/2012

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Signs and Symptoms

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Prof Alyn Morice
Scientific

Respiratory Medicine
Division Cardiovascular and Respiratory Studies
Castle Hill Hospital
Castle Road
Cottingham
HU16 5JQ
United Kingdom

Email	a.h.morice@hull.ac.uk

Study information

Study design	Randomised single centre crossover study
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Hospital
Study type	Diagnostic
Participant information sheet	Not available in web format, please use the contact details below to request a patient information sheet
Scientific title	Validation of the citric acid cough challenge using the KoKo DigiDoser system in healthy volunteers: a 4-week randomised single centre crossover study
Study objectives	The citric acid cough challenge was first reported in humans over 50 years ago. The test was established to allow for the quantification of cough and also as a tool for the assessment of antitussive properties of certain therapies. Since this time many different protocols have been published to measure cough reflex sensitivity these can vary in terms of the nebuliser used, tussive agent, single breath, single dose, dose response and number of coughs required to attain a threshold. In our opinion a definitive method for measuring cough sensitivity needs to be established to allow for standardisation of results from different groups to be compared. The standardisation of this test will lead to a higher quality of research, better drug development and ultimately better patient care.
Ethics approval(s)	Hull and East Riding Local Research Ethics Committee approved on the 26th April 2006 (ref: 06/Q1104/46)
Health condition(s) or problem(s) studied	Artificially induced cough
Intervention	Volunteers were randomised for the order methods to induce artificial cough, i.e., whether the Mefar dosimeter was used first or the KoKo DigiDoser. The following assessments were then performed: 1. Impulse oscillometry 2. Spirometry 3. Citric acid cough challenge
Intervention type	Other
Primary outcome measure	Reproducibility of cough reflex sensitivity to citric acid (measured via inhalation of incremental, doubling concentrations of citric acid until the concentration inducing two or more coughs or five or more coughs is reached)using the modified Devilbiss 646 nebuliser powered by the KoKo DigiDoser. Measured within 1 day comparing baseline challenge and challenges at 1, 2 and 4 hours post-baseline to measure within-day reproducibility.
Secondary outcome measures	To compare the reproducibility of cough reflex sensitivity using the modified Devilbiss 646 nebuliser powered by the KoKo DigiDoser with that of the more commonly used MB2 nebuliser powered by the MB3 mefar dosimeter. Assessed at baseline and then two weeks later to assess between-day reproducibility.
Overall study start date	04/07/2006
Completion date	19/10/2006

Eligibility

Participant type(s)	Patient
Age group	Adult
Lower age limit	18 Years
Sex	Both
Target number of participants	30
Key inclusion criteria	1. Healthy male/female volunteers 2. Male and female subjects of at least 18 years of age 3. Non-smokers or, ex-smokers of at least 12 months 4. Forced expiratory volume in one second (FEV1) greater than 80% of predicted
Key exclusion criteria	1. Female subjects who are pregnant, or lactating, or who are of child bearing potential but are not using contraceptive measures 2. Suffering from any active seasonal allergies 3. Suffering from concomitant disease which may interfere with study procedures or evaluation. 4. Subjects suffering from gastroesophageal reflux taking proton pump inhibitors or any other regular antacid therapy 5. Subjects suffering from post nasal drip syndrome 6. A recent respiratory tract infection within 6 weeks prior to entry on to study 7. Use of medications known to alter the cough reflex 8. Smoking history of greater than 10 pack years
Date of first enrolment	04/07/2006
Date of final enrolment	19/10/2006

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

Respiratory Medicine

Cottingham
HU16 5JQ
United Kingdom

Sponsor information

Hull and East Yorkshire Hospitals NHS Trust (UK)
Hospital/treatment centre

Research and Development Office
Medical Research and Teaching Centre
Daisy Building
Castle Hill Hospital
Castle Road
Cottingham
HU16 5JQ
England
United Kingdom

Phone	+44 (0)1482 461883
Email	James.Illingworth@hey.nhs.uk
Website	http://www.hey.nhs.uk
"ROR"	https://ror.org/01b11x021

Funders

Funder type

Government

Hull and East Yorkshire Hospitals NHS Trust (UK) - Research and Development Grant

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results	10/08/2010		Yes	No