Data limited on asthma and severity of COVID-19
Asthma does not appear to increase risk for contracting the novel coronavirus (COVID-19) or influence its severity, according to new research published in The Journal of Allergy and Clinical Immunology: In Practice.
In severe SARS-CoV-2 infection, a complex immunopathology exists that comprises active viral replication and an armed, overactive immune, and inflammatory response, the researchers said. Cytokines can evoke a cytokine storm syndrome that features elevated markers of inflammation and an acquired immunodeficiency. Disruption of the coagulation cascade in the cytokine storm can lead to a coagulopathy with elevated D-dimers and fibrin split products, reflecting a generalized severe endovascular process.
Tissue injury may then ensue from macro- and microthrombi in the veins and arteries of major organs including the lungs, heart, kidneys, and brain. Evidence of cytokine storm syndrome is present in a high proportion of severely ill patients. However, critical questions remain about the biologic and clinical features that predispose to CSS and critical illness, including underlying comorbidities such as asthma and the medications used to treat them.
Older age and comorbidities, especially heart disease, hypertension, chronic obstructive pulmonary disease (COPD), diabetes, and obesity, are reported risk factors for the development and progression of COVID-19. However, controversy exists as to whether patients with asthma manifest high or elevated rates of COVID-19 incidence. Limited data exist that patients with severe asthma with markedly diminished lung function and receiving monoclonal antibodies are at greater risk than those with less severe disease.
"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 Panettieri Jr., MD, a pulmonary critical care physician and director of the Rutgers Institute for Translational Medicine and Science and co-author of a paper. "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."