Whether inhaled corticosteroids (ICS) should be continued during the pandemic is one of the most common questions asked by patients, their families and health professionals. The answer is definitely yes, although there are some important and interesting caveats to this recommendation.
To set the scene, viral respiratory tract infections are the most common cause of a severe exacerbation of asthma that leads to a hospital admission, in both children and adults. The provoking viruses include human rhinovirus, coronavirus, respiratory syncytial virus and influenza. However, to date, severe exacerbations of asthma do not appear to be a feature of COVID-19 infection, in which viral pneumonia and ARDS are predominant. As a result, asthma exacerbations do not appear to be an important feature of COVID-19 infection, and asthma does not appear to be a specific comorbidity for identifying at-risk individuals.
Turning now to ICS therapy, this represents the most effective preventive treatment available in asthma. It improves symptoms and lung function, and reduces the risk of severe exacerbations including those leading to hospital admission and mortality. It is for this reason that the recent Global Initiative for Asthma (GINA) strategy recommends that ICS should be prescribed to all adolescents and adults with asthma, regardless of severity. Thus, the priority is to decide by what regimen and what dose should ICS be prescribed.
For long-term, regular scheduled maintenance therapy, ICS can be prescribed as either a separate ICS or combined ICS/LABA inhaler. When prescribed in this way, the standard dose which achieves 80 - 90% of the maximum achievable efficacy is about 200 to 250 ug/day of FP, or equivalent. While some patients with severe asthma may need higher doses, most patients require no greater than this daily dose. This standard dose also reduces the risk of systemic adverse effects that may occur with higher doses.
The other regimen by which ICS can be prescribed is through the use of budesonide/formoterol as a reliever inhaler (instead of a short acting beta2-agonist (SABA) such as salbutamol) either alone, or together with budesonide/formoterol maintenance therapy (aka SMART regimen). The use of budesonide/formoterol in this way allows for the dose of ICS to be titrated in accordance with changes in asthma severity, through the vehicle of bronchodilator reliever use. When used like this, budesonide/formoterol reliever therapy reduces the risk of severe exacerbations compared with SABA reliever therapy. This evidence has led GINA to recommend that ICS/formoterol is now the preferred reliever therapy to take in adults and adolescents across the spectrum of asthma severity.
Bottom line: It is essential that all adolescents and adults with asthma are taking ICS during the COVID-19 pandemic; clinical review during this period should include consideration of transferring patients from a SABA to budesonide/formoterol as the reliever therapy, either alone or together with budesonide/formoterol maintenance therapy.