Impact of refractory and unexplained chronic cough on disease burden: a qualitative study

Chronic cough lasting for > 8 weeks is a common medical condition that burdens patients. This study aimed to qualitatively describe knowledge, awareness, experiences, and subtypes of burdens (physical, social, psychological) among Japanese patients with refractory chronic cough (refractory to treatment of underlying relevant medical conditions) and unexplained chronic cough (symptoms of unexplained origin).

This non-interventional, cross-sectional study was conducted between February and March 2021 among patients (aged ≥ 20 years) with self-reported refractory or unexplained chronic cough. Subjects with a history of comorbid respiratory conditions were excluded. Eligible subjects participated in a 60-min online semi-structured interview. Verbatim terms from interviews were qualitatively transcribed and generated into word clouds, followed by a clustering analysis in which meaningful clusters were chosen, manually coded, and utterances and burdens categorized.

A total of 21 participants (95.2% with refractory chronic cough, mean age 53.5 years, and 76.2% being males) with Leicester Cough Questionnaire mean ± standard deviation scores of physical 4.8 ± 1.1, psychological 4.4 ± 1.3, social 4.9 ± 1.4, and total 14.1 ± 3.5 were included. The word cloud identified the most frequently used word ('cough'); etiology ('asthma'); and words associated with change in states ('influence,' 'changing,' 'change') and expressions ('tough,' 'pain,' 'hard,' 'terrible,' 'unpleasant'). The patients experienced 'mental/social burden,' 'physical burden,' 'impact on sleep and meals,' 'impact on work and housework,' 'impact on communication,' 'impact on hobbies and leisure,' and 'economic burden.' By closed coding analysis, the situations or types of burden patients experienced from the cough were ordered sequentially as emotion, working style, acquaintanceship, hobbies and leisure, and sleeping pattern.

The present study indicated that there were two types of participant clusters, in which one showed mainly the burdens in the social communications such as work-related communication and another one showed the burdens of relationships with others. Also, some participants highlighted 'mental burden,' on social life due to the current pandemic. To relieve these burdens, disease awareness and knowledge should be improved for patients with refractory and unexplained chronic cough. Trial registration The trial was registered under UMIN-CTR as UMIN000042772, on 17/12/2020. The study was approved by the Medical Corporation Toukeikai Kitamachi Clinic (IRB registration number: 11001110).