Predictors of objective cough frequency in chronic obstructive pulmonary disease

Jorgen Vestbo, Helen Sumner, Ashley Woodcock, Umme Kolsum, Rachel Dockry, Aili L. Lazaar, Dave Singh, Jørgen Vestbo, Jaclyn A. Smith, Sukh Singh

Research output: Contribution to journalArticlepeer-review


Rationale: Cough is one of the principal symptoms of chronic obstructive pulmonary disease (COPD) but the potential drivers of cough are likely to be multifactorial and poorly understood. Objectives: To quantify cough frequency in an unselected group of subjects with COPD and investigate the relationships between cough, reported sputum production, smoking, pulmonary function, and cellular airway inflammation. Methods: We studied 68 subjects with COPD (mean age, 65.6 ± 6.7 yr; 67.6% male; 23 smokers; 45 ex-smokers) and 24 healthy volunteers (mean age, 57.5 ± 8.9 yr; 37.5% male; 12 smokers; 12 non-smokers). Subjects reported cough severity, cough-specific quality of life, and sputum expectoration and performed spirometry, sputum induction, cough reflex sensitivity to capsaicin, and 24-hour ambulatory cough monitoring. Measurements and Main Results: COPD current smokers had the highest cough rates (median, 9 coughs/h [interquartile range, 4.3-15.6 coughs/h]), almost double that of COPD ex-smokers (4.9 [2.3-8.7] coughs/h; P = 0.018) and healthy smokers (5.3 [1.2-8.3] coughs/h; P = 0.03), whereas healthy volunteers coughed the least (0.7 [0.2-1.4] coughs/h). Cough frequency was not influenced by age or sex and only weakly correlated with cough reflex sensitivity to capsaicin (log C5r=20.36;P=0.004). Reported sputum production, smoking history, and current cigarette consumption strongly predicted cough frequency, explaining 45.1% variance in a general linear model (P <0.001). In subjects producing a sputum sample, cough frequency was related to current cigarette consumption and percentage of sputum neutrophils (P = 0.002). Conclusions: Ambulatory objective monitoring provides novel insights into the determinants of cough in COPD, suggesting sputumproduction, smoking, and airway inflammation may be more important than sensitivity of the cough reflex. Copyright © 2013 by the American Thoracic Society.
Original languageEnglish
Pages (from-to)943-949
Number of pages6
JournalAmerican Journal of Respiratory and Critical Care Medicine
Issue number9
Publication statusPublished - 1 May 2013


  • Capsaicin
  • Cough
  • Neutrophils
  • Smoking
  • Sputum


Dive into the research topics of 'Predictors of objective cough frequency in chronic obstructive pulmonary disease'. Together they form a unique fingerprint.

Cite this