Changing the paradigm of Chronic Cough – the Cough Hypersensitivity Syndrome
Submitting Institution
University of HullUnit of Assessment
Allied Health Professions, Dentistry, Nursing and PharmacySummary Impact Type
HealthResearch Subject Area(s)
Medical and Health Sciences: Cardiorespiratory Medicine and Haematology, Clinical Sciences
Summary of the impact
Research at Hull into hypersensitivity of the airways has provided novel
insights into the
epidemiology and causes of cough, and its burden on patients. This was
achieved by the
development of novel methodologies that allow the rigorous and objective
testing of new and
existing drugs. Patients benefit through the online provision of a
diagnostic tool, and Proctor &
Gamble have successfully exploited the cloned cell receptors in their drug
development
programme resulting in a new range of pharmaceuticals for cough. The work
has underpinned the
standardisation of cough challenge methodology through incorporation in
national and international
healthcare guidelines leading to a widespread improvement in patient
treatment.
Underpinning research
The underpinning research was carried out by Professor Alyn H Morice
(Professor of Respiratory
Medicine at the University of Hull and Hull York Medical School, from his
appointment in 1998 to
present), Dr Laura Sadofsky (Post-Doctoral Research Assistant 2006 to
2011; Lecturer 2011 to
present), Dr Shoaib Faruqi (Lecturer 2007 to 2009; Consultant Respiratory
Physician (2011 to
present) Professor Martin Bland (Professor of Medical Statistics,
University of York 2009 to
present).
In 2006 a group led by Prof Morice demonstrated the true prevalence of
chronic cough; one in ten
of 50 year olds and pointed by its association to the underlying aetiology
of a form of reflux (1).
Previously cough was neglected despite impacting significantly on
patients' quality of life. In a
postal survey of patients requesting information following a Radio 4 Case
Notes programme on
chronic cough, over 800 respondents indicated that they had seen an
average of 6 different
practitioners without successful diagnosis or treatment of their cough
(2).
The underpinning research has provided unique insights into the problem
of chronic cough as an
important component of many common respiratory ailments, proving that
novel cough receptors
underlie the hypersensitivity seen in patients — for example demonstrating
the polymodal TRPA1
nociceptor as an important cough receptor in humans (3). Collaborative
work in Yorkshire has
shown that approximately 12% of the general population suffer from chronic
cough and 7% feel
that this interferes with activities of daily living (1). Unsurprisingly,
this high incidence leads to a
considerable workload in both primary and secondary care. Recently similar
findings have been
reported in an ERS funded study of 10,000 patients from three continents
(presented at 1st
International Cough Conference (ICC), 8th November, Guangzhou, China).
In order to quantify morbidity caused by chronic cough and to allow
interventions to be assessed
an objective measure was developed. The Hull Automated Cough Counter
(HACC) measures the
degree and pattern of coughing both in a clinical and clinical trial
environment. The work of the
Hull Cough Clinic also developed the international standardisation of
cough challenge methodology
allowing for the objective quantification of cough reflex sensitivity.
These methodologies were
standardised in the report of the European Respiratory Society Taskforce
(4). With this platform in
place we have tested both new (TRPA1 antagonists) and existing (opiate)
drugs in an objective
fashion. New cough challenge agonists such as cinnamaldehyde have been
developed and novel
cough receptors described in humans as a result (3).
Research undertaken by the Hull Cough Clinic has successfully challenged
previous dogma that
there were various conditions causing cough and the clinician should
identify each cause and treat
accordingly. We showed gaseous non-acid airway reflux (as opposed to acid
gastro-oesophageal
reflux) was the precipitating feature that sensitises the upper airway
leading to cough. Through an
iterative process relying on extensive patient involvement coupled with
repeated refinement in the
clinic a validated questionnaire was developed, which identifies the
distinguishing features of a
single overarching diagnosis, the Cough Hypersensitivity Syndrome (5).
Validity and sensitivity to
treatment effects has been demonstrated in controlled clinical trials.
The consequences of airway reflux include the previously unrecognised
worsening of a number of
established conditions, such as treatment-resistant asthma, exacerbations
of COPD, idiopathic
pulmonary fibrosis and cystic fibrosis. The research has provided a
paradigm shift in our
understanding of the aetiology of these conditions through the clinical
recognition of airways reflux
and consequent nociceptor hyper-responsiveness.
References to the research
1. Ford AC, Forman D, Moayyedi P, Morice AH. Cough in the community: a
cross sectional
survey and the relationship to gastrointestinal symptoms. Thorax 2006;
61:975-979.
2. Everett CF, Kastelik JA, Thompson RH, Morice AH. Chronic persistent
cough in the
community: A questionnaire survey. Cough 2007; 3(1):5.
3. Birrell MA, Belvisi MG, Grace M, Sadofsky L, Faruqi S, Hele DJ, Maher
SA, Freund-Michel V,
Morice AH. TRPA1 Agonists Evoke Coughing in Guinea-pig and Human
Volunteers. Am J
Respir Crit Care Med 2009.
4. Morice AH, Fontana GA, Belvisi MG, Birring SS, Chung KF, Dicpinigaitis
PV, Kastelik JA,
McGarvey LP, Smith JA, Tatar M, Widdicombe J. ERS guidelines on the
assessment of
cough. Eur Respir J 2007; 29(6):1256-1276.
5. Morice AH, Faruqi S, Wright CE, Thompson R, Bland JM. Cough
hypersensitivity syndrome: a
distinct clinical entity. Lung 2011; 189(1):73-79.
6. Dettmar PW, Strugala V, Fathi H, Dettmar HJ, Wright C, Morice AH. The
online Cough Clinic:
developing guideline-based diagnosis and advice. Eur Respir J 2009;
34(4):819-824.
Details of the impact
The research's identification of the typical clinical characteristics of
chronic cough pointed directly
to gaseous non-acid airway reflux as the precipitating feature which
sensitises the upper airway.
This pioneered a markedly different approach to chronic cough aetiology
and therapy based on the
diagnosis and treatment of reflux and enshrined in the national
guidelines. The proof that up-
regulation of cough receptors underlies the airway hypersensitivity seen
in patients suffering from a
range of respiratory disease pointed the way to new therapeutic avenues
such as the now
widespread use of pro motility agents. The up-regulation of these
nociceptors (demonstrated in
Ref 3) underpins the hypersensitivity hypothesis and is now a major target
for therapy e.g. TRPA1
antagonists such as GRC 17536.
The research has dramatically transformed the view of cough as evidenced
by the ERS and
European Lung Foundation surveys (2013 Congress) of doctor and patient
attitudes. Changing
this common symptom from intractable heart-sink into a distinct clinical
entity allowing novel
treatments greatly impacts on a patient's quality of life.
Specific impacts which have occurred since January 2008 to present
include:
- A company and website (see Ref 6) www.selfnostics.com
offers online cough diagnosis for
patients worldwide, with further advice available at a charge. Since its
launch on 1st March
2012 to 31st July 2013 there have been 9,845 page views
(Google analytics account).
- Development of the Hull Automated Cough Counter to measure the impact
of cough on
patients' lives objectively. It is in clinical use in 3 national cough
centres (Belfast — testimonial
from Senior Lecturer in Medicine; Birmingham and Hull) in the UK and was
chosen by the
sponsors of 5 clinical studies (including Schering Plough, Philips and
Proctor & Gamble) in over
250 patients to objectively measure anti-tussive activity.
- Standardisation of cough challenge methodology and adoption into the
international guidelines,
allowing for drugs to be tested in an objective fashion and for new
agonists to be identified. The
production of the British Thoracic Society and European Thoracic Society
guidelines on chronic
cough and European Respiratory Society guidelines on cough methodology.
Professor Morice
was the Chair and first author on all of these guideline documents. More
recently, guidelines on
the management of cough in lung cancer have also been produced. The
effects of such
national guidelines are difficult to quantify, but the websites of the
British Thoracic Society and
European Thoracic Society indicate a total of over 10,000 downloads of
the guidelines
demonstrating both the degree of the problem and the success in
providing information to
address it.
- Clinical studies have been informed by rational clinical practice.
Cough is a difficult therapeutic
area and most recent studies have failed to show effects greater than
placebo. The resulting
economic benefits are therefore difficult to quantify since drug
development is often halted.
However patients are now spared the promotion of drugs that are without
an adequately proven
evidence base. For example the data from the University of Hull cough
clinics demonstrated an
insignificant effect of SCH169734 in chronic cough allowing Merck
Schering Plough to halt
product development. Testimonial — Chief Clinical Scientist, Merck
Schering Plough.
- Similarly, butamirate (Novartis Consumer Health) had no activity
against challenge whereas the
positive licensed control dextromethorphan was shown to be a potent
antitussive agent.
Unfortunately the latter product continues to be marketed in Europe, but
the British consumer
has been protected. Testimonial — Respiratory Products, Novartis
Consumer Health.
- The underpinning research has also led to nociceptors being cloned and
expressed within
human cells (funded by Proctor & Gamble) and used in house by the
company to test the
effectiveness of potential cough products. Clinical research work has
supported development of
the "Vics First Defence" product range by Proctor & Gamble by
demonstrating product efficacy
sufficient to obtain licensing authorisation. Continued collaboration
between the University of
Hull and the Company is seen as mutually beneficial; highly productive
in terms of clinical
product development and further basic science research. Testimonial -
Section Head Life
Sciences, Proctor & Gamble.
Media coverage — the underpinning research has been given extensive
international media and
press coverage including BBC Radio 4 Case Notes and Inside Health, BBC
News website, The
Daily Mail and The Telegraph (Audience figures are 1.2 million for both
Case Notes and Inside
Health, verified by Paula McGrath, Producer, BBC Science Radio Unit).
Parts of the underpinning research were undertaken in collaboration with
other HEIs as follows:
Ref 1 - Researchers at the University of Leeds co-ordinated the
distribution of a questionnaire
which gathered survey data for Professor Morice's research.
Ref 2 - The panel which developed the guidelines was organised and
chaired by Professor Morice,
and included members from Imperial College London, King's College London,
the University of
Florence and Einstein College New York. Professor Morice was lead author
on the guidelines.
Ref 3 - The research on human volunteers and human cells was undertaken
at Hull, and the
research on guinea pigs at Imperial College London.
Ref 5 - The research was predominantly undertaken by Hull researchers,
with statistical analysis
by the University of York.
Sources to corroborate the impact
Website www.selfnostics.com -
corroborating that the company and website have been
established. Financial information for www.selfnostics.com
(available confidentially on request) -
corroborating the revenues from the website.
Senior Lecturer in Medicine, Belfast Cough Clinic — testimonial
corroborating the value of the
HACC in clinical assessments.
British Thoracic Society cough guidelines (available online at http://www.brit-thoracic.org.uk/Portals/0/Clinical%20Information/Cough/Guidelines/coughguidelinesaugust06.pdf)
— demonstrating
the contribution of the research to altering British guidelines.
European Thoracic Society guidelines (available online at http://www.ers-education.org/pages/default.aspx?id=2005
— demonstrating the contribution of the research to altering European
guidelines.
Web management data from the websites of the British Thoracic Society and
European Thoracic
Society — corroborating 22,510 hits on the chronic cough guidelines.
Chief Clinical Scientist, Merck Schering Plough — testimonial
corroborating the economic benefits
of not pursuing the development of SCH169734 following use of the HACC.
Respiratory Products, Novartis Consumer Health — testimonial
corroborating the economic benefits
of not pursuing the development of butamirate following use of the cough
challenge methodology.
Section Head Life Sciences, Proctor & Gamble — testimonial
corroborating the economic benefits of
launching the "First Defence" product range following use of the cloned
cell nociceptors.