Remote exposure to Western wildfire smoke causing heart and lung problems nationwide: Study

Wildfire smoke wafting across the country from North America West blazes may be leading to cardiac and respiratory issues thousands of miles away, a new study has found.

Medical visits for heart and lung issues in the Baltimore region surged by 20 percent during six days in June 2023, when smoke from Western Canada blazes drifted across the continent, according to the study, published on Friday in JAMA Network Open.

These fires, the study authors explained, created a vast plume that traveled about 2,000 miles, creating poor air quality on the East Coast of the United States and causing the uptick in doctor visits.

“Baltimore had very dark skies, and we could all smell the smoke in the air,” lead author Mary Maldarelli, a pulmonary critical care fellow at the University of Maryland School of Medicine, said in a statement.

“But most importantly, my patients came in to me saying they were coughing quite a bit more and needed their medications more often," Maldarelli continued. "They felt much sicker than they usually did when these wildfires occurred.”

To divulge whether the smoke-filled days were linked to quantifiable impacts, Maldarelli and a team of data scientists and visualization experts analyzed satellite and Environmental Protection Agency (EPA) data to identify six "hotspot" days. Those were the days in which smoke-related pollution exceeded the EPA's standards for safe air quality in all 23 counties of Maryland.

During that period — divided into June 6-8 and June 28-30 — the scientists found a 9.4-fold and 7.4-fold surge, respectively, in fine particulate matter pollution levels, in comparison to all other days in 2023.

The researchers then sifted through a database of almost 2 million de-identified patient records, comparing medical visits for cardiac and respiratory conditions in June 2023 to those in June 2018 and 2019.

Ultimately, they observed a 55 percent spike in the general risk that a heart- or lung-related outpatient visit occurred during the hotspot days.

"These patients tended to be older, non-smokers, and more socio-economically affluent than typical patients who see their doctors for cardiovascular conditions on good air quality days," corresponding author Bradley Maron, a professor at the UMD School of Medicine, said in a statement.

The researchers also identified an 18-percent rise in the likelihood that patients went to the doctor for cardiopulmonary complications on those days.

With more extreme wildfire events presumably on the horizon, the scientists stressed the importance of equipping doctors with better tools to cope with such circumstances.

In particular, they said that their findings may indicate that lower-income patients are not getting the care they need amid smoke-filled conditions.

Mark Gladwin, the dean of the School of Medicine and who was not an author of the study, emphasized a need to leverage his institution's capability to provide at-risk patients with anticipatory care.

“There may be crucial ways we can prevent cardiovascular complications on polluted smoke air days simply by providing them with telehealth visits or other ways to access care," Gladwin said.