• Study of over 2,000 Detroit residents hospitalised with COVID-19 suggests living in a more polluted area is linked with a greater likelihood of requiring mechanical ventilation and being admitted to intensive care.
  • Living near sewage water dischargers and in close proximity to heavy traffic strongly linked to a higher risk of death from COVID-19.
  • Findings underscore urgent need to tackle the public health crisis of pollution, researchers say.

 

Embargo: 2301H UK time Thursday 8 July

Long-term exposure to high levels of air pollutants, especially fine particulate matter (PM2.5), appears to have a significant influence on outcomes for people hospitalised with COVID-19, according to a large, multicentre observational study being presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) held online this year.

The greater the exposure, the greater the risk, researchers found. Each small (ug/m³) increase in long-term PM2.5 exposure was associated with more than three times the odds of being mechanically ventilated and twice the likelihood of a stay in ICU.

“Our study calls attention to the systemic inequalities that may have led to the stark differences in COVID-19 outcomes along racial and ethnic lines”, says Dr Anita Shallal from the Henry Ford Hospital in Detroit, USA. “Communities of colour are more likely to be located in areas closer to industrial pollution, and to work in businesses that expose them to air pollution”.

According to the American Lung Association, Detroit is the 12th most polluted city in the USA measured by year-round fine particle pollution (PM2.5) [1]. Ambient air pollution—including potentially harmful pollutants such as PM2.5 and toxic gases emitted by industries, households, and vehicles—can enhance inflammation and oxidative stress in the respiratory system, exacerbating pre-existing lung disease. Air pollution has been linked with worse health outcomes, including increased risk of dying, from respiratory viruses like influenza.

To examine the association between air pollution and the severity of COVID-19 outcomes, researchers retrospectively analysed data from 2,038 adults with COVID-19 admitted to four large hospitals within the Henry Ford Health System between March 12 and April 24, 2020. Patients were followed until May 27, 2020.

The researchers collected data on where participants lived as well as data from the US Environmental Protection Agency and other sources on local levels of pollutants including PM2.5, ozone, and lead paint (percentage of houses built before 1960). They explored the association between COVID-19 outcomes and exposure to PM2.5, ozone, lead paint, traffic, hazardous waste, and waste water discharge.

They found that patients who were male, black, obese, or had more severe long-term health conditions were much more likely to be mechanically ventilated and admitted to the ICU. So too were patients living in areas with higher levels of PM2.5 and lead paint.

Even after accounting for potentially influential factors including age, BMI, and underlying health conditions, the analysis found that being male, obese, and having more severe long-term health conditions were a good predictor of dying following admission. Similarly, higher PM2.5 was an independent predictor for mechanical ventilation and ICU stay, but not a greater risk of dying from COVID-19.

The authors point out that their study was observational, so can’t establish cause. They add that while they adjusted for several influential factors, it is still possible that other factors which could not be fully controlled for, including severity of disease at time of presentation, may contribute to the outcomes observed.

Notes to editors:

[1] Most Polluted Cities | State of the Air | American Lung Association

The study received no funding.

The authors declare no conflicts of interest.

This press release is based on oral presentation 1238 at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID). All accepted abstracts have been extensively peer reviewed by the congress selection committee. There is no full paper at this stage, but the authors are happy to answer your questions. The research has not yet been submitted to a medical journal for publication. As it is an oral presentation, there is no poster.

 

For full abstract, click here

 

Selected Media Coverage

Reuters (Newswire)

Daily Mail (UK and international)

Noticias Ao Minuto (Portugal)

US News & World Report (USA)