MedWire News: Respiratory viral infections significantly increase the risk for exacerbations in patients with chronic obstructive pulmonary disease (COPD), researchers report.

"Patients with COPD have frequent exacerbations which lead to increased airway inflammation and often subsequent hospitalization," explain Terence McManus (Belfast Health and Social Care Trust, UK) and colleagues in the journal Respiratory Medicine.

Bacterial infections are associated with about half of all COPD exacerbations, but less is known about the role of viral infections, the authors explain.

To investigate further, they collected data from 136 patients with COPD who were experiencing an exacerbation, 68 with stable COPD and 16 disease-free smokers.

All the participants underwent lung tests and provided sputum samples that were examined for the presence of 12 different respiratory viruses.

The team found that 37% of COPD patients who were experiencing an exacerbation were infected with a respiratory virus, compared with just 12% of patients with stable COPD and 12% of smokers without the condition.

In addition, six patients experiencing an exacerbation were infected with more than one respiratory virus, whereas none of the other participants had a dual infection.

Rhinoviruses, which cause the common cold, were the most common viruses identified among the participants.

McManus and team conclude: "This study supports the hypothesis that respiratory viral infection is associated with exacerbations of COPD."

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