Study suggests that asthma does not increase the severity of COVID-19

“Older age and conditions such as heart disease, high blood pressure, chronic obstructive pulmonary disease, diabetes and obesity are reported risk factors for the development and progression of COVID-19,” said Reynold A. Panettieri Jr., a pulmonary critical care physician and director of the Rutgers Institute for Translational Medicine and Science and co-author of a paper published in the Journal of Allergy and Clinical Immunology.

“However, people with asthma – even those with diminished lung function who are being treated to manage asthmatic inflammation – seem to be no worse affected by SARS-CoV-2 than a non-asthmatic person. There is limited data as to why this is the case – if it is physiological or a result of the treatment to manage the inflammation.”

How might awareness of SARS-CoV-2 affect the health of people with asthma?

Since the news has focused our attention on the effects of COVID-19 on vulnerable people, those with asthma may have become hyper-vigilant about hygiene and social distancing. There is also evidence that people are being more attentive to taking their medication during the pandemic.

Social distancing could also improve asthma control since people who are self-isolating are not exposed to seasonal triggers such as allergens or respiratory viruses.

What effect might inhaled steroids have?

Inhaled corticosteroids also may reduce the virus’ ability to establish an infection, however, studies have shown that steroids may decrease the body’s immune response and worsen the inflammatory response.

Future studies should address whether inhaled steroids decrease the risks of SARS-CoV-2 infection, and whether these effects are different depending on the steroid type.

In what way does age play a role?

A person’s susceptibility to and severity of COVID-19 infection increases with age, therefore, age-adjusted studies could help us better understand if age is a factor in explaining why asthma patients may not be at greater risk for infection.

Children and young adults with asthma suffer mainly from allergic inflammation, while older adults who experience the same type of airway inflammation can also suffer from eosinophilic asthma — a more severe form. In these cases, people experience abnormally high levels of a type of white blood cell that helps the body fight infection, which can cause inflammation in the airways, sinuses, nasal passages and lower respiratory tract, potentially making them more at risk for a serious case of COVID-19.

In addition, an enzyme attached to the cell membranes in the lungs, arteries, heart, kidney and intestines that has been shown to be an entry point for SARS-CoV-2 into cells is increased in response to the virus, but it is still unclear how this enzyme affects the ability of SARS-CoV-2 to infect people with asthma.

How might conditions in addition to asthma affect a person’s risk of infection?

If SARS-CoV-2 is a disease that causes dysfunction in the cells that line blood vessels throughout the body, then diabetes, heart disease, obesity and other diseases associated with this condition may make people more susceptible to the virus than those who are asthmatic. However, older people with asthma who also have high blood pressure, diabetes or heart disease may have similar instances of COVID-19 as non-asthmatics with those conditions.