To the Editor,
We read carefully the research letter “Is asthma protective of
COVID-19?” by Carli et al recently published.1Important topic for asthma patients in the coronavirus disease 2019
(COVID-19) pandemic were considered, including that until recently weak
evidence that patients with chronic respiratory disorders are at a lower
risk of being infected or becoming severely ill with Severe Acute
Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).
Reflecting only about previous reports from China and Italy where asthma
was underrepresented in COVID-19 patients, the authors accept the
heterogeneous condition that it is asthma, speculating that T2-immunity,
interferon-mediated immune responses and increased number of eosinophils
in the airways could have a protective effect against COVID-19
severity.1
The epidemiology of COVID-19 is changing rapidly with new data. More
recent reports from the United States of America and from several
European countries, in particular the United Kingdom (UK), states a
higher asthma prevalence in patients with COVID-19, suggesting that
asthma is more common in COVID-19 patients than it was previously
reported in Asia and in the first European surveys.2Data from the UK Biobank, a large prospective case-control study, found
an asthma prevalence of 17,9% in 605 COVID-19 hospitalized patients,
mostly of them adults, surpassing the prevalence of asthma in the
general population.3
Besides that, in the OpenSAFELY Collaborative Study (UK), it was found a
significant increased risk of severe CoViD-19 in patients with asthma,
including death, in particular related with the recent use of oral
corticosteroid (OCS).4 These findings can indicate an
increased asthma severity and/or poor control and, in accordance with
data from previous coronavirus outbreaks, that systemic corticosteroids
were associated with a higher viral load.5
We agree with Carli et al1 that further studies
focused on asthma and its different phenotypes are needed to provide a
better understanding of the impact of SARS-CoV-2 infection in patients
with asthma.6 Nevertheless, for the moment, it seems
crucial that patients with asthma do not stop their controller
medication, that may lead to a higher risk of asthma exacerbations,
increased OCS use and higher probability to emergency room access and
hospitalization that represent themselves significant risk factors for
coronavirus exposure and spread.
In conclusion, according with the available data, patients with asthma
must still be included in the high-risk groups for COVID-19 and more
data are needed to understand the relationship between asthma and
COVID-19.