Condition category
Respiratory
Date applied
20/12/2010
Date assigned
07/04/2011
Last edited
07/04/2014
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

Dr Emma Young

ORCID ID

Contact details

University Hospitals South Manchester
North West Lung Research Centre
Southmoor Road
Manchester
M23 9LT
United Kingdom
emma.young@manchester.ac.uk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

DNIC1; G0900449

Study information

Scientific title

Diffuse Noxious Inhibitory Controls in chronic cough: a randomised, 4-way cross-over study of 20 healthy subjects and 20 patients with chronic cough

Acronym

DNIC

Study hypothesis

We hypothesise that:
1. Inhibitory mechanisms control coughing in healthy subjects, but not in patients with chronic cough, and
2. Females have less effective inhibitory mechanisms compared to males

Ethics approval

North West 6 Research Ethics Committee - Greater Manchester South approved on the 14th December 2010 (ref: 10/H1003/104)

Study design

Randomised four-way cross-over study

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

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

Condition

Chronic cough

Intervention

Basal conditions:
During both blocks of capsaicin inhalation (block 1 and block 2) participants will not place their hand in a water bath and will be instructed to cough freely.

Control conditions:
During both blocks of capsaicin inhalation (block 1 and block 2) participants will place their hand in a non-painful warm water bath (37°C) and will be instructed to cough freely.

Cold water conditions:
During one of the blocks of capsaicin inhalation (block 1 or 2) participants will place their hand in a painful cold water bath (10°C). During the other block participants will place their hand in a non-painful warm water bath (37°C). The order of the blocks is randomised. Participants will cough freely throughout.

Conscious cough suppression conditions:
During one of the blocks (block 1 or 2) participants will place their hand in a non-painful warm water bath (37°C) and will be asked to "try not to cough". During the other block participants will place their hand in a non-painful warm water bath (37°C) and will be instructed to cough freely. The order of the blocks is randomised.

The duration of this clinical trial will range from 2 - 5 weeks.

Intervention type

Drug

Phase

Not Applicable

Drug names

Capsaicin

Primary outcome measures

Effect of painful cold water bath on cough response.

The primary and secondary outcome measures will be recorded following each of the four randomised interventions. Each intervention will take place at least 48 hours apart.

Secondary outcome measures

1. Effect of conscious cough suppression on cough response
2. Comparison of effects by group and gender

The primary and secondary outcome measures will be recorded following each of the four randomised interventions. Each intervention will take place at least 48 hours apart.

Overall trial start date

04/01/2011

Overall trial end date

04/01/2012

Reason abandoned

Eligibility

Participant inclusion criteria

Healthy volunteers:
1. Aged over 18 years old, either sex
2. Normal lung function
3. No current or past history of chronic cough or chronic respiratory illness
4. No current or past history of chronic pain, irritable bowel syndrome or chronic headaches
5. No current or past history of psychiatric illness
6. No current history of reflux disease or post-nasal drip syndrome

Chronic cough patients:
1. Aged over 18 years old, either sex
2. Chronic cough, defined as a cough lasting longer than 8 weeks despite investigation and/or treatment trials for cough variant asthma, post-nasal drip and gastro-oesophageal reflux disease
3. Normal chest x-ray
4. Normal lung function
5. Can safely omit long-acting bronchodilators (if taking)

Participant type

Healthy volunteer

Age group

Adult

Gender

Both

Target number of participants

40 (20 healthy volunteers and 20 chronic cough patients)

Participant exclusion criteria

1. Recent upper respiratory tract infection (less than 4 weeks)
2. Pregnancy or breast-feeding
3. Use of angiotensin converting enzyme (ACE) inhibitors
4. Any centrally acting medication which could alter the sensitivity of the cough reflex
5. History of drug or alcohol abuse
6. Current smoker or ex-smoker with greater than 10 pack year smoking history

Recruitment start date

04/01/2011

Recruitment end date

04/01/2012

Locations

Countries of recruitment

United Kingdom

Trial participating centre

University Hospitals South Manchester
Manchester
M23 9LT
United Kingdom

Sponsor information

Organisation

University Hospitals of South Manchester NHS Foundation Trust (UK)

Sponsor details

c/o Dr Andrew Maines
Ground Floor
Education & Research Centre
Southmoor Road
Manchester
M23 9LT
United Kingdom
andrew.maines@manchester.ac.uk

Sponsor type

Government

Website

http://www.uhsm.nhs.uk/Pages/default.aspx

Funders

Funder type

Research council

Funder name

Medical Research Council (MRC) (UK) (ref: G0900449)

Alternative name(s)

MRC

Funding Body Type

private sector organisation

Funding Body Subtype

other non-profit

Location

United Kingdom

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

Publication citations

Additional files

Editorial Notes