# Impact of nasal and inhaled corticosteroids on SARS-CoV-2 infection susceptibility

## TL;DR

Nasal and inhaled corticosteroids may increase SARS-CoV-2 infection risk in adults but not in children, according to a surveillance study.

## Contribution

This study is the first to show age-dependent associations between corticosteroid use and SARS-CoV-2 infection risk in adults and children.

## Key findings

- NCS and ICS use were linked to higher SARS-CoV-2 infection risk in adults.
- No association was found between corticosteroid use and infection risk in children.
- The associations were modified by age, with stronger effects observed in adults.

## Abstract

It is unknown whether nasal corticosteroid (NCS) or inhaled corticosteroid (ICS) use impacts the susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

We sought to examine the associations of NCS and ICS use with the risk of SARS-CoV-2 infection among individuals with allergic rhinitis or asthma.

This is a prospective, multicenter, SARS-CoV-2 surveillance study of households with children. Nasal swabs were obtained from participants every 2 weeks with additional collections based on coronavirus disease 2019–related symptoms. In our primary adjusted models, we examined the association of NCS or ICS use at study entry (in participants with allergic rhinitis or asthma, respectively) with the time to the first SARS-CoV-2–positive quantitative PCR testing using Cox proportional hazard regression.

There were 2211 participants in the 1113 households included. The associations of NCS and ICS use with the risk of SARS-CoV-2 infection were modified by age (P for both interactions <.05). NCS and ICS use were individually associated with higher risks of SARS-CoV-2 infection among adults (adjusted hazard ratio [aHR] = 1.88, 95% CI: 1.14-3.12, P = .01, and aHR = 2.15, 95% CI: 1.003-4.63, P = .049, respectively). The association of NCS use with the risk of SARS-CoV-2 infection in adults was consistent in a series of sensitivity analyses. There was no association of NCS or ICS use with the risk of SARS-CoV-2 infection in children.

Our findings suggest that the risk of SARS-CoV-2 infection is increased in adults who use NCS but not in children. Similar, albeit less consistent, age-dependent findings were observed for ICS use. While the results of this observational study should be interpreted with caution, they emphasize the need to conduct studies to understand potential mechanisms that could explain these findings.