Regular use of inhaled corticosteroids (ICS) does not appear to either increase or decrease mortality from COVID-19 in patients with asthma or COPD, say UK researchers.

In response to speculation that ICS may confer a potential protective effect in COVID-19, analysis of a large database initially showed an increased risk of death related to ICS prescribing within the past four months.

But a more detailed look at the data of 148,557 COPD patients and 818,490 people with asthma found that this apparently harmful association could be explained by small health differences between those prescribed ICS and those that were not.

Writing in Lancet Respiratory Medicine, the researchers concluded that the results do not support the suggestion that ICS could be used to protect against asthma-related death in COPD or asthma.

Their analysis found that people with COPD who were prescribed ICSs were at increased risk of COVID-19-related death compared with those prescribed LABA–LAMA combinations (adjusted HR 1·39 [95% CI 1·10–1·76]).

In asthma, patients prescribed high-dose ICS were at an increased risk of death (1·55 [1·10–2·18]), whereas those given a low or medium dose ICS were not (1·14 [0·85–1·54]), compared with those on short-acting beta-agonist (SABA) only.

But the researchers stressed that these observed increased risks of death from COVID-19 could be plausibly explained by confounding factors related to disease severity not recorded in the datasets used.

“Evidence suggests there is neither a demonstrable benefit nor clear harm from ICS use against COVID-19-related mortality among people with COPD and asthma, and so no evidence supports that patients should alter their ICS therapies during the ongoing pandemic,” they concluded.

Evidence from ongoing randomised controlled trials will be needed to determine the role of ICS in the treatment of COVID-19 in those without asthma or COPD, they added.

In an accompanying editorial, Professor Dave Singh from the University of Manchester and Professor David Halpin Consultant Respiratory Physician at the Royal Devon and Exeter Hospital said patients with COPD and asthma were understandably concerned about COVID-19 infection and look to their clinicians for answers on their risks.

This study “provides some insights, but not conclusive answers”, they write.

“Overall, the analysis is confounded and does not provide definitive answers that patients and clinicians need, although it hints that ICS use does not provide a strong protective effect.”

A different conclusion may have been reached if clinical factors such as disease severity and history of exacerbations were taken into account, they added.

“Until more information is available, patients with asthma and COPD who are stable while using ICS must continue on their treatment during the ongoing COVID-19 pandemic.”