Population-level trends in asthma and chronic obstructive pulmonary disease emergency department visits and hospitalizations before and during the coronavirus disease 2019 pandemic in the United States.

backgroundPrevious studies have identified reductions in exacerbations of chronic lung disease in many locales after onset of the coronavirus disease 2019 (COVID-19) pandemic.

objectiveTo evaluate the population-level impacts of COVID-19 on asthma and chronic obstructive pulmonary disease (COPD) exacerbations-with a focus on disadvantaged communities-in the United States.

methodsWe analyzed 2016 to 2020 county-level data on asthma and COPD acute care use, with myocardial infarction hospitalizations as a comparator condition. We linked this with county-level lower respiratory disease mortality data. We calculated rates of emergency department (ED) visits, hospitalizations, and deaths and evaluated changes using linear regressions adjusted for year and county-fixed effects. For a supplementary analysis, we calculated ED visit rates nationwide for asthma, COPD, or any diagnosis using the 2016 to 2020 National Hospital Ambulatory Medical Care Survey.

resultsOur county-level data included 685 counties in 13 states. Rates of each outcome fell in 2020. In adjusted analyses, we found large reductions in asthma and COPD ED visit rates (eg, a 21.5 per 10,000-person reduction in COPD ED visits; 95% confidence interval, -23.8 to -19.1), with smaller reductions in hospitalizations and chronic lower respiratory mortality. Disadvantaged communities had mostly higher baseline rates of respiratory morbidity and larger absolute reductions in some outcomes. Among 90,808 ED visits in the National Hospital Ambulatory Medical Care Survey, asthma ED visits/y fell 33% during the pandemic and COPD visits by 51%; overall ED visits fell by only 7%.

conclusionOnset of the COVID-19 pandemic coincided with reductions in acute care utilization for asthma and COPD. Understanding the mechanism of this reduction might inform future efforts to prevent exacerbations.