Impact of current cough on health-related quality of life in patients with COPD

BACKGROUND Cough and sputum production are frequent in chronic obstructive pulmonary disease (COPD). The objective of this study was to examine the relationship between cough and sputum production and health-related quality of life in COPD. METHODS A cross-sectional study was conducted in the French Initiatives COPD cohort and assessed cough and sputum production within the past 7 days using the cough and sputum assessment questionnaire (CASA-Q), health-related quality of life, spirometry, smoking status, dyspnea, exacerbations, anxiety and depression, and comorbidities. RESULTS One hundred and seventy-eight stable COPD patients were included (age, 62 [56-69] years, 128 male, forced expiratory volume in 1 second [FEV1]: 57 [37-72] % predicted) (median [Q1-Q3]). In univariate analyses, health-related quality of life (Saint George's respiratory questionnaire total score) was associated with each CASA-Q domain and with chronic bronchitis, exacerbations, dyspnea, FEV1, depression, and anxiety. All four domains introduced separately were independently associated with health-related quality of life. When introduced together in multivariate analyses, only the cough impact domain remained independently associated with health-related quality of life (R2=0.60). With chronic bronchitis (standard definition) instead of the CASA-Q, the R2 was lower (R2=0.54). CONCLUSION This study provides evidence that current cough in the previous 7 days is an important determinant of health-related quality of life impairment in stable COPD patients.