Frequent productive cough signals higher risk of disease burden in asthma and COPD: Study

UK: Frequent productive cough is a key indicator of adverse clinical outcomes across asthma and/or chronic obstructive pulmonary disease (COPD), states an article published in Respiratory Medicine. 

Patients with obstructive lung diseases commonly present respiratory symptoms such as shortness of breath, chest tightness, cough, and sputum but these symptoms are not specific to either asthma or chronic obstructive pulmonary disease. Persistent cough with sputum production is an important clinical trait in  COPD.

Recent studies have shown that frequent productive cough(Persistent cough with sputum )is associated with lung function decline, exacerbation risk, and increased risk of mortality in patients with COPD. Less is known about the characteristics of asthmatic patients with frequent productive coughs. However, this clinical trait in asthma has been associated with increased healthcare utilization and accelerated lung function decline. Frequent productive cough can be assessed using the St George's Respiratory Questionnaire (SGRQ) which inquires about the frequency of cough and sputum (phlegm) production over the previous 3 months in patients.

Rod Hughes, Respiratory and Immunology, Clinical, AstraZeneca, Cambridge, UK, and his research team sought to determine the occurrence and associated outcomes of a frequent productive cough in patients with physician-assigned asthma and/or COPD.

Researchers analyzed data of a large global observational cohort (NOVELTY) of >7000 real-world patients with a diagnosis of asthma and/or COPD. Frequent productive cough was defined as cough and sputum production most or several days/week for the past 3 months (scoring ≥3 for both SGRQ questions). Logistic regression was used to examine the relationships between baseline disease characteristics and exacerbations over 12 months of follow-up. Baseline SGRQ data were available for 7125 patients, of whom 31.3% had a frequent productive cough.

Key findings of the study:

• Frequent productive cough was more common in asthma + COPD (38.8%) and COPD (38.1%) than asthma (25.0%), increasing with physician-assessed severity, and in current versus former and never smokers.

• Patient-reported symptomatic worsening was more common in patients with frequent productive cough than those without.

• Reduced post-bronchodilator FEV1 and history of pollutant exposure at home/work were associated with frequent productive cough in all diagnoses.

• Patients with baseline frequent productive cough were more likely to have ≥1 exacerbation over the subsequent 12 months, including exacerbations requiring hospital admission and those treated with oral corticosteroids.

Researchers conclude that frequent productive cough, as a common clinical trait was associated with worse clinical and patient-reported disease and poorer clinical outcomes across asthma and/or COPD. The analysis confirms that both cough and sputum production is frequent chronic symptoms in patients with asthma and/or COPD.

Effective treatment strategies to reduce frequent productive coughs are needed for the management of these patients. Research into the underlying pathologic mechanisms is required to support such therapy development, the authors wrote.

Reference:

The study titled, "Frequent productive cough: Symptom burden and future exacerbation risk among patients with asthma and/or COPD in the NOVELTY study," was published in the journal Respiratory Medicine. 

DOI: https://doi.org/10.1016/j.rmed.2022.106921