Chronic cough management: Practical guidelines and PICO-based evidence for screening and investigation

Dichapong Kanjanawasee,^1,2 Orapan Poachanukoon,³ Thitiwat Sriprasart,⁴ Naricha Chirakalwasan,^4,5 Narongkorn Saiphoklang,⁶ Athipat Athipongarporn,⁷ Anchalee Senavonge,^8,9 Harutai Kamalaporn,¹⁰ Natthawan Sanguanwong,^5,11 Wat Mitthamsiri,¹² Chirawat Chiewchalermsri,¹³ Bandarn Suetrong,¹⁴ Aphichat Suwanchanratsamee,¹⁵ Pongsakorn Tantilipikorn,^1,16 Monthira Maneerattanaporn,¹⁷ Pariyanan Jaruchinda,¹⁸ Theerasuk Kawamatawong,¹⁹ Varisara Luvira,²⁰ Premsuda Sombuntham,²¹ Mongkhon Sompornrattanaphan,^1,22 Triphoom Suwanwech,^1,16 Nonpavit Chotchai,²⁰ Kiat Ruxrungtham,^8,23 Watchara Boonsawat,²⁴ John Daniel Brannan,²⁵ Woo-Jung Song,²⁶ Prapaporn Pornsuriyasak²⁷

Affiliations:
¹ Center of Research Excellence in Allergy & Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
² Biodesign Innovation Center, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
³ Center of Excellence for Allergy, Asthma and Pulmonary Diseases, Thammasat University, Pathum Thani, Thailand
⁴ Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
⁵ Excellence Center for Sleep Disorders, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
⁶ Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
⁷ Department of Pediatrics, Phra Nakhon Si Ayutthaya Hospital, Phra Nakhon Si Ayutthaya, Thailand
⁸ Division of Allergy and Clinical Immunology, Department of Pediatric, Faculty of Medicine, Chulalongkorn university, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
⁹ BNH hospital, Bangkok, Thailand
¹⁰ Division of Pediatric Pulmonology, Department of Pediatrics, Faculty of Medicine, Ramathibodi hospital, Mahidol University, Bangkok, Thailand
¹¹ Department of Physiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
¹² Allergy and Clinical Immunology Division, Department of Medicine, Phramongkutklao Hospital, Bangkok, Thailand
¹³ Department of Medicine, Panyananthaphikkhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi, Thailand
¹⁴ Department of Pediatrics, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
¹⁵ Saraburi Hospital, Saraburi, Thailand
¹⁶ Division of Rhinology & Allergy, Department of Otorhinolaryngology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
¹⁷ Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
¹⁸ Department of Otolaryngology, Phramongutklao Hospital, Bangkok, Thailand
¹⁹ Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
²⁰ Department of Community, Family, and Occupational Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
²¹ Department of Otolaryngology head and neck, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
²² Division of Allergy and Clinical Immunology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
²³ Center of Excellence in Vaccine Research and Development (Chula VRC); and School of Global Health (Chula SGH), Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
²⁴ Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
²⁵ School of Medicine and Public Health, University of Newcastle, University Drive, Callaghan, Australia
²⁶ Department of Allergy and Clinical Immunology Allergy, Asthma & COPD Center Airway Sensation & Cough Research Laboratory Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
²⁷ Department of Clinical Epidemiology and Biostatistics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Thailand

Abstract

Chronic cough is a common clinical condition requiring comprehensive assessment. This review employs a symptom-focused approach, prioritizing the presenting symptom of “chronic cough” to mirror real-world clinical practice. Ten key questions regarding the investigations in the uncertain areas were systematically addressed based on the PICO framework and applying the GRADE system for evidence synthesis to provide the strength of recommendation and quality of evidence for key questions. Practical diagrams were developed to facilitate clinical decision-making. The initial evaluation involves screening for red flag signs requiring urgent attention, followed by a detailed history-taking and physical examination. A chest radiograph is recommended as the first-line investigation. The primary objective of the initial evaluation is to identify the cause and initiate appropriate treatment. If history and physical examination prove insufficient for a definitive diagnosis, referral to a specialist is advised for further specific testing. The recommendations on specific testing include fractional exhaled nitric oxide for cough variant asthma, nasal endoscopy or digital endoscopy (optional) for upper airway cough syndrome, paranasal sinus computed tomography (CT) for chronic rhinosinusitis, and laryngoscopy for hoarseness. Spirometry is for the diagnosis of obstructive airway diseases, and peak flow variability or bronchial challenge tests are complements particularly if asthma is suspected. Gastroesophageal reflux (GERD) investigations are for patients with chronic cough without typical GERD symptoms. Sinus radiographs and chest CT are not routinely recommended. Our guideline distinguishes itself by prioritizing a symptom-based clinical evaluation to guide clinicians toward the most probable diagnosis, streamlining the diagnostic process.
Key words: cough, chronic cough, diagnosis, persistent cough, evidence-based, guideline, gastroesophageal reflux, primary care, refractory chronic cough, respiratory, unexplained chronic cough

Citation:
Kanjanawasee, D., Poachanukoon, O., Sriprasart, T., Chirakalwasan, N., Saiphoklang, N., Athipongarporn, A., Senavonge, A., Kamalaporn, H., Sanguanwong, N., Mitthamsiri, W., Chiewchalermsri, C., Suetrong, B., Suwanchanratsamee, A., Tantilipikorn, P., Maneerattanaporn, M., Jaruchinda, P., Kawamatawong, T., Luvira, V., Sombuntham, P., Sompornrattanaphan, M., Suwanwech, T., Chotchai, N., Ruxrungtham, K., Boonsawat, W., Brannan, J. D., Song, W. J., Pornsuriyasak, P. (2024). Chronic cough management: Practical guidelines and PICO-based evidence for screening and investigation. Asian Pac J Allergy Immunol, 42(4), 305-317. https://doi.org/10.12932/ap-191124-1976