Chronic cough - a review

Correspondance: Ossur Ingi Emilsson, oingi@hi.is 

Chronic cough is common in the general population, with a prevalence of about 10% among adults. It can be caused by a range of conditions within and outside the airways, such as asthma, COPD, cancer, infections, and smoking, or it can occur as an adverse effect of medication, among other causes. Chronic cough can also be a disease in its own right. It generally has a major impact on patients' quality of life. The workup of cough should always include spirometry and a chest radiograph, and further investigations are guided by the clinical presentation. When cough persists despite treatment of possible underlying causes, or when no cause is found after workup, it is most often because the neural reflex that triggers cough has become hypersensitive. The reasons for this are not fully understood, but studies have shown that the network of sensory nerves in the airways is often more dense and that the central nervous system's ability to suppress cough is reduced. In these cases, treatments aimed at dampening the cough reflex can be used. This review covers the workup, pathophysiology, and management of patients with chronic cough in more detail, describes new developments in treatment, and current Icelandic research projects on chronic cough.