Regardless of vaccination status, exposure to air pollution is associated with an increased risk for COVID-19 hospitalization, according to a letter to the editor published in the American Journal of Respiratory and Critical Care Medicine. Zhonghua Chen, PhD, and colleagues conducted a study of 50,010 individuals aged 12 and older with
COVID-19 to examine the links of long- and short-term exposure to nitrogen dioxide (NO2), fine particles (PM2.5), and ozone with COVID-19- related hospitalizations. A total of 34.0% and 4.2% of participants were fully and partially vaccinated before COVID-19 diagnosis, respectively. Overall, 6.1% had COVID-19-related hospitalization within 30 days after COVID-19 diagnosis. Vaccination significantly reduced the risk for hospitalization, with adjusted ORs of 0.46 and 0.16 for partially and fully vaccinated patients, respectively, compared with unvaccinated, after adjustment for covariates and air pollutants. With and without adjustment for vaccination status, exposures to PM2.5 and NO2 were associated with an increased risk for COVID-19-related hospitalization.