Researchers at the University of Newcastle and Imperial College London have provided evidence that a conventional treatment for common respiratory diseases such as chronic obstructive pulmonary disease (COPD) can actually lead to worse health outcomes when used to treat symptoms caused by respiratory virus infections.
New research published in leading International journal Nature Communications has revealed that the use of inhaled corticosteroids during viral infection-induced exacerbations of COPD can actually suppress anti-microbial immunity whilst increasing mucus production and lung bacterial load providing new insight into the link to a higher incidence of pneumonia in this patient group.
Associate Professor Nathan Bartlett, Head of the HMRI Viral Immunology and Respiratory Disease Group, says there is no question that steroids are effective for people with chronic inflammatory diseases such as asthma and COPD. “But there are caveats to that, and what this research is helping to show is that there are beneficial and potentially detrimental effects associated with their use. By considering and addressing the key negative effects such as suppressed immunity and mucus production we could potentially enhance the efficacy of these commonly used therapies.”
Because COPD damages the airways and lung tissue and compromises resistance to infection, something as simple as a common cold can cause severe respiratory complications.
“Corticosteroids are frequently prescribed during COPD exacerbations and do have clear benefit to the patient in the short term. However prolonged use with high doses can cause unwanted side effects, notably increased risk of pneumonia,” Associate Professor Bartlett says.
“We’ve now identified mechanisms by which steroids interfere with the response to infection enabling us to now focus our research on developing treatments that promote airway immune responses to counteract the negative effects of steroids and improve overall benefit to the patient.”
With COPD there’s no cure; therapies can only treat symptoms and complications. “If we can minimise the severity of the exacerbations whilst protecting against the occurrence of secondary infections and pneumonia that cause further permanent damage to the lungs then we will improve the quality of life for people living with COPD,” Associate Professor Bartlett says.
“They’ll have more years of better lung function and improved quality of life.”