Epidemiology of cough

Patients with cough may be conveniently divided into those with acute, usually viral, illness and those with chronic cough. Acute cough represents the largest single cause of consultation in primary care, whereas chronic cough is one of the commonest presentations in respiratory medicine. The world-wide market in cough treatments is several billion dollars. In both syndromes, cough sensitivity is upregulated, but the inflammation giving rise to cough is localised to the larynx and large airways in acute cough. Whilst this is also true of cough-predominant asthma, the origin of cough in chronic disease may also lie in the oesophagus, nose or sinuses leading to errors in diagnosis and treatment.