Public health measures designed to reduce the spread of the COVID-19 virus may have fostered a substantial side benefit: hospital admissions for COPD were reduced by 53%, new data published in The American Journal of Medicine reveal. This is likely due to a drop in circulating seasonal respiratory viruses such as influenza, according to the researchers at the University of Maryland School of Medicine (UMSOM) who analyzed data at the 13-hospital University of Maryland Medical System (UMMS).

Hospitalizations for COPD are commonly driven by flare-ups where symptoms are triggered by such factors as tobacco smoke, air pollution and respiratory infections. Seasonal respiratory viruses, including those that cause the common cold or influenza, trigger nearly half of those flare-ups, UMSOM scientists say.

In the wake of a marked drop in COPD admissions during the pandemic, researchers theorized that COVID-19 behavior changes – a mix of stay-at-home orders, social distancing, masking mandates and strict limitations on large gatherings – not only protected against COVID-19, but they may have also reduced exposure to other respiratory infections. Conversely, they worry that the return to normal behavior may lead to more COPD flare-ups.

To understand what may have occurred to reduce COPD admissions, the researchers compared weekly hospital admissions for COPD in the pre-COVID-19 years of 2018 and 2019, with admissions after the COVID-19 public health measures were instituted. At UMMS, those measures were implemented before April 1, 2020, so the investigators chose the same five-month period in each year for their comparison, April 1 to Sept. 30.

“We assessed a variety of possible causes that could affect COPD admissions including the presence of multiple diseases or medical conditions and the frequency of COPD exacerbations,” said co-lead author Jennifer Y. So, MD, UMSOM Assistant Professor of Medicine and COPD specialist at UMMC. “We found a 53 percent drop in COPD admissions throughout UMMS during COVID-19. That is substantial, but equally significant, the drop in weekly COPD admissions was 36 percent lower than the declines seen in other serious medical conditions, including congestive heart failure, diabetes and heart attack.”

As more and more people are vaccinated against COVID-19 and many of the public health measures of the past year are relaxed, the researchers warn that a full return to normal may again expose COPD patients to the familiar seasonal triggers.

“Our study shows there’s a silver lining to the behavior changes beyond protecting against COVID-19,” said senior author Robert M. Reed, MD, UMSOM Professor of Medicine and pulmonologist at the University of Maryland Medical Center (UMMC). “If we completely eliminate masks and distancing during cold and flu season, we’ll allow all those viruses that have been effectively suppressed to come raging back. There could be a lot of illness.”

“This is a compelling study that raises some important public health questions about protecting our most vulnerable patient populations after we are finished with the COVID-19 pandemic. I certainly think it warrants a fuller discussion,” said UMSOM Dean E. Albert Reece, MD, PhD, MBA, University Executive Vice President for Medical Affairs and the John Z. and Akiko K. Bowers Distinguished Professor.


So JY, et al. Decline in COPD Admissions During the COVID-19 Pandemic Associated with Lower Burden of Community Respiratory Viral Infections. The American Medical Journal of Medicine. doi: https://doi.org/10.1016/j.amjmed.2021.05.008