Chronic cough comorbidity increases disease severity in COPD

Chronic obstructive pulmonary disease (COPD) patients with comorbid chronic cough appear to exhibit a more severe disease in terms of accompanying respiratory symptoms and healthcare utilization, lung function, and inflammation in blood, according to a study.

Researchers used data from a nested cohort of 43,271 adults from the Copenhagen General Population Study, among whom 8,181 (19 percent) had COPD with 796 (10 percent) of these having chronic cough.

Individuals with COPD and chronic cough comorbidity had a median total score on Leicester Cough Questionnaire of 17.7 (25th–75th percentiles, 16.0–18.9), which corresponded to 5.9 (5.3–6.3) for the physical domain, 5.6 (4.9–6.3) for the psychological domain, and 6.3 (5.8–6.8) for the social domain.

Among individuals with COPD, those with vs without chronic cough were more likely to have sputum production (60 percent vs 8 percent), wheezing (46 percent vs 14 percent), dyspnoea (66 percent vs 38 percent), chest pain/tightness (9 percent vs 4 percent), night-time dyspnoea (8 percent vs 3 percent), episodes of acute bronchitis/pneumonias in the last 10 years (45 percent vs 25 percent), and visits to a general practitioner in the past 12 months (53 percent vs 37 percent).

Furthermore, patients with the comorbidity had lower forced expiratory volume in 1 second (FEV1) percentage of predicted (81 percent vs 89 percent), FEV1/forced vital capacity (0.64 vs 0.66), as well as higher levels of inflammatory biomarkers in blood (eg, high-sensitive C-reactive protein, fibrinogen, leukocytes, neutrophils, eosinophils and IgE).

The present data suggest that chronic cough in individuals with COPD is associated with a more severe disease phenotype, which may aid in the management of COPD in the future, the researchers said.