Condition category
Signs and Symptoms
Date applied
05/06/2009
Date assigned
18/09/2009
Last edited
25/09/2012
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Prof Alyn Morice

ORCID ID

Contact details

Respiratory Medicine
Division Cardiovascular and Respiratory Studies
Castle Hill Hospital
Castle Road
Cottingham
HU16 5JQ
United Kingdom
a.h.morice@hull.ac.uk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

AcadMed CTU04/05

Study information

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

Acronym

Study hypothesis

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

Hull and East Riding Local Research Ethics Committee approved on the 26th April 2006 (ref: 06/Q1104/46)

Study design

Randomised single centre crossover study

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Diagnostic

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet

Condition

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

Phase

Not Applicable

Drug names

Primary outcome measures

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 trial start date

04/07/2006

Overall trial end date

19/10/2006

Reason abandoned

Eligibility

Participant 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

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

30

Participant 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

Recruitment start date

04/07/2006

Recruitment end date

19/10/2006

Locations

Countries of recruitment

United Kingdom

Trial participating centre

Respiratory Medicine
Cottingham
HU16 5JQ
United Kingdom

Sponsor information

Organisation

Hull and East Yorkshire Hospitals NHS Trust (UK)

Sponsor details

Research and Development Office
Medical Research and Teaching Centre
Daisy Building
Castle Hill Hospital
Castle Road
Cottingham
HU16 5JQ
United Kingdom
+44 (0)1482 461883
James.Illingworth@hey.nhs.uk

Sponsor type

Government

Website

http://www.hey.nhs.uk

Funders

Funder type

Government

Funder name

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

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

1. 2010 results in http://www.ncbi.nlm.nih.gov/pubmed/20698995

Publication citations

  1. Results

    Wright CE, Jackson J, Thompson RL, Morice AH, Validation of the ERS standard citric acid cough challenge in healthy adult volunteers., Cough, 2010, 6, 8, doi: 10.1186/1745-9974-6-8.

Additional files

Editorial Notes