COPD and Asthma May Not Be Risk Factors for COVID-19, Study Says

Chronic obstructive pulmonary disease (COPD) and asthma are not risk factors for severe coronavirus disease 2019 (COVID-19) complications, according to a recent study published in the Journal of Allergy and Clinical Immunology: In Practice.

The study contradicts the widely accepted assumption that patients with respiratory obstructive diseases are more at risk for ICU admissions and death than those without; this was largely determined by older evidence showing that respiratory diseases are risk factors for more severe reactions to common cold viruses.

At the beginning of the pandemic, early publications from China showed that the prevalence of chronic obstructive pulmonary diseases in patients with COVID-19 was lower than expected, concluding that they are not risk factors. However, the studies often combined people with asthma and people with COPD into 1 “chronic obstructive respiratory disease” group, suggesting that chronic pulmonary diseases may have gone underdiagnosed during that time, the authors said.

While inhaled corticosteroids (ICSs) are considered immunosuppressive drugs and thus raised concern that they could make someone more vulnerable to COVID-19, they reduce exacerbations and may even provide a protective effect against the virus, the authors said.

To determine if COPD and asthma were risk factors, researchers collected data on 595 adult patients who were hospitalized with COVID-19 between March 18, 2020 and April 17, 2020 at the University Hospital of Liege in Belgium, using the hospital’s electronic medical records.

Patients were classified into 3 groups:

• 57 (9.6%) patients with COPD
• 46 (7.7%) patients with asthma
• 492 (82.7%) patients without respiratory obstructive diseases

Patients with COPD were often older and current or ex-smokers and had higher emphysema rates than patients in the other 2 groups. They also had a higher prevalence of hypertension, gastroesophageal reflux, cardiopathy, chronic renal failure, and history with cancer. One-third of them used ICSs, with 19% receiving a high dose and 44% receiving a moderate dose.

ICS use was also recorded for 70% of patients with asthma, half of whom received high doses.

Overall, ICU admission occurred in one-fifth of patients with COPD or asthma. Nine (19.6%) patients with COPD, 10 (17.5%) of patients with asthma, and 69 (14%) of patients without respiratory diseases were hospitalized in the ICU.

Although the prevalence of ICU admission was not associated with COPD, asthma, or ICS use, researchers noted that male gender and obesity were found to be risk factors in the multivariate analysis. Men had 1.9 times (95% CI, 1.1–3.2) more risk of an ICU stay. Obesity increased ICU risk by 8.5 times (95% CI, 5.1–14.1).

Additionally, 16 (34.8%) patients with COPD, 4 (7%) patients with asthma, and 67 (13.8%) patients without respiratory diseases died during hospitalization for COVID-19.

Investigators said that COPD was found to be a predictor of death in the univariate analysis but not in the models that were adjusted for age and gender for the multivariate analysis, suggesting that the increased risk was likely linked to the higher rate of comorbidities recorded and the older age of the COPD group.

The factors that were found to be associated with death during hospitalization were male gender, older age, cardiopathy, and immunosuppressive disease. Cardiopathy is a common comorbidity in patients with COPD.

Use of ICS and oral corticosteroids were not found to increase the risk of severe infections in patients. Researchers said that it is possible that ICS is dose-dependently associated with reduced angiotensin converting enzyme 2 (ACE2) mRNA expression, the receptor often used by SARS-CoV-2, the virus that causes COVID-19, to enter the cells. Because of this, researchers recommended, in line with current international guidelines, that physicians not decrease ICS doses during SARS-CoV-2 infection.

Further, intubation length according to airway status was not associated with asthma, however, prolonged intubations was found in patients with COPD.

The results on whether smoking is a COVID-risk factor were contradictory to evidence demonstrating that smoking is linked to increased risk of respiratory diseases because the proportion of current smokers in the study was lower than the general population of Belgium. However, the investigators suggested that smoking may provide a protective effect against COVID-19 by killing cells that have ACE2 receptors, and thus, blocking the virus from entering cells.

Reference

Calmes D, Graff S, Maes N, et al. Asthma and COPD are not risk factors for ICU stay and death in case of SARS-CoV2 infection. J Allergy Clin Immunol Pract. January 2021;9(1):160-169. doi: 10.1016/j.jaip.2020.09.044