Worldwide prevalence, risk factors and burden of chronic cough in the general population: a narrative review.

Background and Objective: Chronic cough is one of the commonest complaints requiring medical attention that significantly impacts on the patient's quality of life. In this review, we focus on chronic cough prevalence, risk factors, and health burden among the general adult population based on recent reports, which will be helpful for a better understanding of the global burden of chronic cough. Methods: A narrative search of Medline was performed for articles and their lists of references published using the keywords "chronic cough", "chronic bronchitis", "epidemiology", "prevalence", "risk factor", "burden", "quality of life", "adult" and "general population". Key Contents and Findings: Although there is a growing literature on the prevalence of chronic cough in the general population from different countries, the prevalence of chronic cough in different populations cannot be directly compared because of the use of varying definitions of chronic cough. Generally, the prevalence of chronic cough is higher in Europe and North America than in Asia. Regarding the risk factors for chronic cough, several have been identified, including age, smoking, asthma, allergic rhinitis, and rhinosinusitis, whereas for other imputed factors, such as occupational exposure, air pollution, and obesity, these remain inconclusive. Although chronic cough is usually not life-threatening, the physical and psychological impact of chronic cough is obvious, leading to substantial healthcare resource utilization, especially for the elderly or those with comorbidities. Conclusions: Chronic cough is a common symptom in the general population that can be associated with a deterioration of quality of life and with increased burden. The identification of risk factors and associated co-morbidities will help towards an improved management of this condition. There is an urgent need to apply the standard definition of chronic cough in future research, so that comparisons of the prevalence and other findings across populations can be made.