Chronic cough: epidemiology.

Chronic cough is perhaps the commonest symptom of medical importance with some 12% of the general population having the symptom on a daily or weekly basis. Chronic cough causes a large degree of morbidity, with both the physical e.g. incontinence, and the psychological e.g. social isolation, domains. The causes of chronic cough are numerous, but fall into two broad categories; that causing an asthma-like syndrome characterized by eosinophilic infiltration of the airways, and oesophageal disease, particularly weakly acid reflux. Failure to make, particularly this latter, diagnosis leads to enormous consequences in terms of loss of employment, healthcare utilisation and a psychosocial morbidity.