Original Article Allergy Asthma Immunol Res. 2016 March;8(2):146-155. http://dx.doi.org/10.4168/aair.2016.8.2.146 pISSN 2092-7355 • eISSN 2092-7363
Defining Chronic Cough: A Systematic Review of the Epidemiological Literature Woo-Jung Song,1 Yoon-Seok Chang,1,2 Shoaib Faruqi,3 Min-Koo Kang,1 Ju-Young Kim,1 Min-Gyu Kang,4 Sujeong Kim,5 Eun-Jung Jo,6 Seung-Eun Lee,6 Min-Hye Kim,7 Jana Plevkova,8 Heung-Woo Park,1 Sang-Heon Cho,1* Alyn H. Morice3* 1
Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea 3 Centre for Cardiovascular and Metabolic Research, Hull York Medical School, Castle Hill Hospital, University of Hull, Cottingham, East Yorkshire, United Kingdom 4 Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea 5 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea 6 Department of Internal Medicine, Pusan National University College of Medicine, Busan, Korea 7 Department of Internal Medicine, Ewha Woman’s University School of Medicine, Seoul, Korea 8 Department of Pathophysiology and Simulation Centre, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic 2
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Purpose: Recent evidence suggests a global burden of chronic cough in general populations. However, the definitions vary greatly among epidemiological studies, and none have been validated for clinical relevance. We aimed to examine previous epidemiological definitions in detail and explore the operational characteristics. Methods: A systematic review was conducted for epidemiological surveys that reported the prevalence of chronic cough in general adult populations during the years 1980 to 2013. A literature search was performed on Pubmed and Embase without language restriction. Epidemiological definitions for chronic cough were classified according to their components, such as cutoff duration. Meta-analyses were performed for the male-to-female ratio of chronic cough prevalence to explore operational characteristics of epidemiological definitions. Results: A total of 70 studies were included in the systematic review. The most common epidemiological definition was identified as ‘cough ≥3 months’ duration without specification of phlegm (n=50); however, it conflicted with the cutoff duration in current clinical guidelines (cough ≥8 weeks). Meta-analyses were performed for the male-to-female ratio of chronic cough among 28 studies that reported sex-specific prevalence using the most common definition. The pooled male-to-female odds ratio was 1.26 (95% confidence interval 0.92-1.73) with significant heterogeneity (I 2 =96%, P
Defining Chronic Cough: A Systematic Review of the Epidemiological Literature Woo-Jung Song,1 Yoon-Seok Chang,1,2 Shoaib Faruqi,3 Min-Koo Kang,1 Ju-Young Kim,1 Min-Gyu Kang,4 Sujeong Kim,5 Eun-Jung Jo,6 Seung-Eun Lee,6 Min-Hye Kim,7 Jana Plevkova,8 Heung-Woo Park,1 Sang-Heon Cho,1* Alyn H. Morice3* 1
Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea 3 Centre for Cardiovascular and Metabolic Research, Hull York Medical School, Castle Hill Hospital, University of Hull, Cottingham, East Yorkshire, United Kingdom 4 Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea 5 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea 6 Department of Internal Medicine, Pusan National University College of Medicine, Busan, Korea 7 Department of Internal Medicine, Ewha Woman’s University School of Medicine, Seoul, Korea 8 Department of Pathophysiology and Simulation Centre, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic 2
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Purpose: Recent evidence suggests a global burden of chronic cough in general populations. However, the definitions vary greatly among epidemiological studies, and none have been validated for clinical relevance. We aimed to examine previous epidemiological definitions in detail and explore the operational characteristics. Methods: A systematic review was conducted for epidemiological surveys that reported the prevalence of chronic cough in general adult populations during the years 1980 to 2013. A literature search was performed on Pubmed and Embase without language restriction. Epidemiological definitions for chronic cough were classified according to their components, such as cutoff duration. Meta-analyses were performed for the male-to-female ratio of chronic cough prevalence to explore operational characteristics of epidemiological definitions. Results: A total of 70 studies were included in the systematic review. The most common epidemiological definition was identified as ‘cough ≥3 months’ duration without specification of phlegm (n=50); however, it conflicted with the cutoff duration in current clinical guidelines (cough ≥8 weeks). Meta-analyses were performed for the male-to-female ratio of chronic cough among 28 studies that reported sex-specific prevalence using the most common definition. The pooled male-to-female odds ratio was 1.26 (95% confidence interval 0.92-1.73) with significant heterogeneity (I 2 =96%, P
