ABSTRACT
Chronic cough (i.e. cough lasting >8 weeks) has a global prevalence of approximately 10% and is associated with substantial patient burden, including social, psychological, and physical impairments. This burden can be long-lasting, with some patients experiencing cough for many years. Although chronic cough is often a symptom of respiratory diseases (e.g. interstitial lung disease, chronic obstructive pulmonary disease) or is associated with comorbid conditions (e.g. asthma, gastroesophageal reflux disease) and may resolve after targeted treatment of these conditions, some patients continue to cough despite optimal treatment of associated conditions (refractory chronic cough (RCC)) or have no identifiable conditions presumed to be contributing to the cough (unexplained chronic cough (UCC)). As both RCC and UCC are diagnoses of exclusion, it is critical to perform a thorough initial patient assessment with adherence to diagnostic guidelines to accurately identify RCC and UCC and provide appropriate treatment. Primary care physicians may be in an important position to provide the initial diagnostic workup of patients with chronic cough as well as identify when referral to specialists (e.g. pulmonologists, allergists, otolaryngologists) is appropriate. In this narrative review, current diagnosis and management guidelines for chronic cough are summarized and recommendations for diagnostic workup in a primary care setting are provided. Increased appreciation of chronic cough as a distinct condition, rather than as only a symptom of other diseases, may help overcome current challenges in diagnosing and managing chronic cough and reduce patient burden.
Acknowledgments
This study was supported by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA. Writing and editorial assistance were provided under the direction of the authors by Aarthi Gobinath, PhD, and Jenna Lewis, MA, ELS, of MedThink SciCom, with support from Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.
Declaration of interest
No potential conflict of interest was reported by the authors.
Declaration of funding
Funding for writing and editorial assistance for this manuscript was provided by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co, Inc., Kenilworth, NJ, USA.
Declaration of financial/other relationships
PK reports personal fees from AstraZeneca, Bayer, Bionorica, Chiesi, GlaxoSmithKline PLC, Klosterfrau, Menarini, MSD, Novartis, and Willmar Schwabe and other support (for a phase 3 investigative cough study) from MSD; all support was outside the submitted work.
MB has served as a consultant for ALK, Bellus, Covis Pharma, Merck, Pfizer, Rx Bandz, Sanofi/Regeneron, and Stallergenes Greer.
PD has paid consultancies or advisory board positions with Bayer HealthCare Pharmaceuticals, Bellus Health Inc, Merck Sharp & Dohme Corp, and Shionogi.