Understanding patient experience of chronic cough in interstitial lung disease.

Rationale: Chronic cough is a common symptom in patients with interstitial lung disease (ILD), negatively contributing to health-related quality of life. Despite this, there is limited information and understanding on the experience of this group of patients with chronic cough. This study aimed to explore the symptom experiences for chronic cough in patients with ILD to identify its characteristics and impacts. Methods: A qualitative study using semi-structured telephone interviews was undertaken in 16 adults with a diagnosis of ILD of any type and severity. Patients were recruited from a quaternary referral centre in Melbourne, Australia. Interviews were transcribed verbatim and coded by two researchers using thematic analysis. Results: Patients (age range: 39-87 years, forced vital capacity: 53-107% predicted and diffusing capacity of the lung for carbon monoxide: 28-89% predicted) experienced a spectrum of cough severity and characteristics, including both dry and productive coughs. The impact of chronic cough included physical symptoms, social and emotional difficulties, and interference with work and vocational participation. Management strategies used to relieve cough included mucolytics, opiates, throat lozenges, warm drinks, pacing, breath control, relaxation exercises, movement, continuous positive airways pressure and supplemental oxygen. Patients expressed a need for further information and education regarding chronic cough, including its triggers and management. Conclusions: This study highlights the experience and significance of chronic cough in patients with ILD. The nature and severity of chronic cough in patients with ILD appears to be more heterogeneous than previously described, with physical, social and emotional impacts contributing to symptom burden.