(HealthDay News) — The incidence of COVID-19 is increased in association with long-term exposure to airborne pollutants, according to a study published online Jan. 10 in Occupational & Environmental Medicine.
Giovanni Veronesi, Ph.D., from the University of Insubria in Varese, Italy, and colleagues examined the association between long-term exposure to airborne pollutants and severe acute respiratory syndrome coronavirus 2 incidence up to March 2021 among residents of Varese aged 18 years and older. The rate ratios and additional numbers of cases were estimated per 1 µg/m3 increase in air pollutants from single-pollutant and bipollutant models.
The researchers identified 4,408 cases among 62,848 residents. The annual average fine particulate matter (PM2.5) exposure was 12.5 µg/m3. Independent associations with COVID-19 were seen for age, living in a residential care home, history of stroke and medications for diabetes, hypertension, and obstructive airway diseases. PM2.5 was associated with a 5.1% increase in the rate of COVID-19 in single-pollutant multivariable models, yielding 294 additional cases per 100,000 person-years. In bipollutant models, the association was confirmed, excluding residents in residential care homes and after further adjustment for area-based indicators of socioeconomic status and public transportation use. For PM10, nitrogen dioxide and nitrogen monoxide, the findings were similar. There was a 2% decrease in disease rate in association with ozone, which was reversed in bipollutant models.
“The COVID-19 cumulative incidence risk connected to long-term exposure to airborne pollutants suggests that outdoor pollution can sustain the disease rate after its temporal peak and irrespective of national or regional quarantine/lockdown periods,” the authors write.