{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T12:14:16Z","timestamp":1788264856804,"version":"build-2803163510"},"reference-count":32,"publisher":"BMJ","issue":"1","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"Ministry of Health and Welfare, Republic of Korea","award":["HF22C0011"],"award-info":[{"award-number":["HF22C0011"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open Resp Res"],"accepted":{"date-parts":[[2026,8,16]]},"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Chronic cough affects approximately 10% of adults and is increasingly recognised as a distinct clinical condition. This symptom has increasingly been associated with significant outcomes such as pneumonia. Nevertheless, few large long-term population-based studies have been conducted.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This retrospective cohort study was performed using nationwide claims data from the Health Insurance Review and Assessment Service in South Korea from 2013 to 2020. Adult patients who visited outpatient clinics for cough (International Classification of Diseases, 10th Revision: R05) were enrolled. Chronic cough was defined as \u22658 visits or \u226556 days. Patients with pneumonia within 2 years before and 6 months after the index date were excluded. The main outcome was incident pneumonia during the 3 year follow-up period. The association between chronic cough and incident pneumonia was evaluated using Cox proportional hazards models, with HRs adjusted for age, sex, comorbidities and Charlson comorbidity index. Sensitivity analyses and subgroup analyses by sex and age were also performed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 385\u2009417 participants (28\u2009706 with chronic cough and 356\u2009711 controls), the incidence of pneumonia was higher in the chronic cough group (18.87 vs 11.32 per 1000 person-years). Chronic cough was independently associated with an elevated risk of pneumonia (adjusted HR 1.13; 95% CI 1.06 to 1.19; p&lt;0.001), and the association was robust across multiple sensitivity analyses with alternative exposures. The subgroup analysis showed a stronger association among men (HR 1.72) than among women (HR 1.39) and among adults aged 40\u201379 years, with the highest risk observed among adults aged 40\u201349 years (HR 1.37).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Chronic cough was independently associated with increased pneumonia risk, especially in middle-aged and male patients. Clinicians should be aware that chronic cough may signal increased vulnerability to lower respiratory tract infections (eg, pneumonia) and consider preventive strategies, including vaccination and close monitoring, for high-risk individuals.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjresp-2025-003484","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:25:21Z","timestamp":1788261921000},"page":"e003484","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Risk of pneumonia in adults with chronic cough: a nationwide cohort study"],"prefix":"10.1136","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4180-5580","authenticated-orcid":false,"given":"Man Young","family":"Park","sequence":"first","affiliation":[{"name":"Korea Institute of Oriental Medicine, Daejeon, South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beom-Joon","family":"Lee","sequence":"additional","affiliation":[{"name":"Division of Allergy, Immune and Respiratory System, Department of Internal Medicine, College of Korean Medicine, Kyung Hee University, Kyung Hee University, Seoul, South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kwan-Il","family":"Kim","sequence":"additional","affiliation":[{"name":"Division of Allergy, Immune and Respiratory System, Department of Internal Medicine, College of Korean Medicine, Kyung Hee University, Kyung Hee University, Seoul, South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun-Hwan","family":"Lee","sequence":"additional","affiliation":[{"name":"Korea Institute of Oriental Medicine, Daejeon, South Korea"},{"name":"Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA"},{"name":"Korean Convergence Medical Science, KIOM School, University of Science & Technology (UST), Daejeon, South Korea"},{"name":"Athinoula A. Martinos Center for Bioimedical imaging, Department of Radiology, Massachusettes General Hospital, Harvard Medical School, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"2026090104251782000_13.1.e003484.1","doi-asserted-by":"publisher","DOI":"10.1183\/09031936.00218714"},{"key":"2026090104251782000_13.1.e003484.2","doi-asserted-by":"crossref","first-page":"2300","DOI":"10.21037\/jtd-22-1435","article-title":"Worldwide prevalence, risk factors and burden of chronic cough in the general population: a narrative review","volume":"15","author":"Yang","year":"2023","journal-title":"J Thorac Dis"},{"key":"2026090104251782000_13.1.e003484.3","doi-asserted-by":"publisher","DOI":"10.1007\/s00408-015-9701-2"},{"key":"2026090104251782000_13.1.e003484.4","doi-asserted-by":"crossref","DOI":"10.1183\/23120541.00739-2022","article-title":"Epidemiology of unexplained chronic cough in adults: a population-based study","volume":"9","author":"Arinze","year":"2023","journal-title":"ERJ Open Res"},{"key":"2026090104251782000_13.1.e003484.5","doi-asserted-by":"publisher","DOI":"10.1016\/j.chest.2017.10.016"},{"key":"2026090104251782000_13.1.e003484.6","doi-asserted-by":"crossref","DOI":"10.1183\/13993003.01136-2019","article-title":"ERS guidelines on the diagnosis and treatment of chronic cough in adults and children","volume":"55","author":"Morice","year":"2020","journal-title":"Eur Respir J"},{"key":"2026090104251782000_13.1.e003484.7","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(21)00393-7"},{"key":"2026090104251782000_13.1.e003484.8","doi-asserted-by":"crossref","first-page":"1544","DOI":"10.1056\/NEJMcp1414215","article-title":"Chronic Cough","volume":"375","author":"Smith","year":"2016","journal-title":"N Engl J Med"},{"key":"2026090104251782000_13.1.e003484.9","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1016\/j.jaip.2024.10.046","article-title":"Cough Reflex Hypersensitivity as a Key Treatable Trait","volume":"13","author":"Song","year":"2025","journal-title":"J Allergy Clin Immunol Pract"},{"key":"2026090104251782000_13.1.e003484.10","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1016\/j.chest.2017.05.038","article-title":"Risk Factors for Chronic Cough Among 14,669 Individuals From the General Population","volume":"152","author":"\u00c7olak","year":"2017","journal-title":"Chest"},{"key":"2026090104251782000_13.1.e003484.11","doi-asserted-by":"publisher","DOI":"10.1183\/13993003.00007-2016"},{"key":"2026090104251782000_13.1.e003484.12","doi-asserted-by":"crossref","DOI":"10.1183\/23120541.00735-2020","article-title":"Aspiration and severe exacerbations in COPD: a prospective study","volume":"7","author":"Cvejic","year":"2021","journal-title":"ERJ Open Res"},{"key":"2026090104251782000_13.1.e003484.13","doi-asserted-by":"publisher","DOI":"10.1164\/ajrccm.153.5.8630597"},{"key":"2026090104251782000_13.1.e003484.14","doi-asserted-by":"publisher","DOI":"10.1378\/chest.129.1_suppl.222S"},{"key":"2026090104251782000_13.1.e003484.15","doi-asserted-by":"publisher","DOI":"10.1016\/j.rmed.2012.11.018"},{"key":"2026090104251782000_13.1.e003484.16","doi-asserted-by":"crossref","DOI":"10.1186\/s12890-017-0496-1","article-title":"Long-term prognosis of chronic cough: a prospective, observational cohort study","volume":"17","author":"Koskela","year":"2017","journal-title":"BMC Pulm Med"},{"key":"2026090104251782000_13.1.e003484.17","doi-asserted-by":"crossref","DOI":"10.1183\/23120541.00697-2023","article-title":"Chronic cough associated with COPD exacerbation, pneumonia and death in the general population","volume":"10","author":"Landt","year":"2024","journal-title":"ERJ Open Res"},{"key":"2026090104251782000_13.1.e003484.18","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1111\/resp.14169","article-title":"Risk factors for chronic cough in adults: A systematic review and meta-analysis","volume":"27","author":"Zhang","year":"2022","journal-title":"Respirology"},{"key":"2026090104251782000_13.1.e003484.19","doi-asserted-by":"crossref","unstructured":"Lugade AA , Bogner PN , Thanavala Y . 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