Patients with asthma with chronic cough are more at risk of asthma exacerbations and worse clinical outcomes, according to a recent study reported in the journal Allergy and Asthma Proceedings.1 They were also more likely to have impairment of daily activities and productivity.

This single-center prospective study enrolled 323 adults with stable asthma visiting a hospital in China from September 2016 to October 2020. The patients were randomized into two groups: one with chronic cough with 127 patients and the other group had 196 patients without chronic cough. The participants were followed up for one year to assess asthma exacerbations. Cough symptom score, cough VAS and the LCQ (Chinese version) were used to assess cough frequency, severity and cough-related quality of life - physical, social, and psychological - in patients with asthma and chronic cough.

When data of the two groups was analyzed and compared, after adjusting for other symptoms of asthma such as dyspnea, wheezing, and chest tightness, it was found that asthmatic patients with chronic cough tended to be older and have more airflow obstruction. Their asthma control was poor with correspondingly poor quality of life along with higher prevalence of underlying conditions (≥3) such as uncontrolled rhinitis, chronic obstructive pulmonary disease, bronchiectasis and anxiety or depression.

Blood eosinophil and monocyte counts were higher in the chronic cough group as were the eosinophil and neutrophil percentage in the sputum, although the sputum macrophages were considerably low.

The frequency of asthma exacerbations of moderate-to-severe intensity was higher in this group of patients with upper respiratory tract infection acting as a trigger for the acute exacerbations, which often necessitated use of systemic steroids and hospitalizations. Patients with asthma and chronic cough reported disruption in activities of daily life along with greater loss in work productivity.

This study illustrates the clinical characteristics of asthma patients with chronic cough. It has shown that these patients are more prone to exacerbations and have significant coexisting chronic respiratory diseases, indicative of increased airway inflammation (eosinophilic) and airflow obstruction. The poorly controlled asthma had significant adverse effects on their quality of life. Chronic cough therefore needs to be managed and controlled and antitussives may be required besides stepping-up the dose of inhaled steroids or a trial of leukotriene receptor antagonists.

Reference

1. Deng SJ, et al. Chronic cough in asthma is associated with increased airway inflammation, more comorbidities, and worse clinical outcomes. Allergy Asthma Proc. 2022 May 1;43(3):209-219. doi: 10.2500/aap.2022.43.220022.