The American Heart Association is alerting the public to the heightened health risks posed by the simultaneous occurrence of wildfire smoke and extreme summer heat, a situation currently affecting parts of the United States due to drifting smoke from Canadian wildfires and rising temperatures. According to the organization, this combination creates a potentially deadly scenario, particularly for individuals with chronic health conditions such as heart disease.
“Extreme heat and wildfire smoke each carry major risks, especially for people with chronic health conditions including heart disease. The combination of the two is extremely dangerous,” said Manesh R. Patel, M.D., FAHA, volunteer president of the American Heart Association, chief of the division of cardiology at Duke University School of Medicine. “We want people to be mindful of the increased risk and take steps to protect themselves and their loved ones.”
While respiratory issues are often the primary concern with wildfire smoke, Patel emphasized the serious impact on cardiovascular health. “Wildfire smoke contains a lot of pollutants including fine, microscopic particles linked to cardiovascular risk. There is a lot of strong scientific evidence that smoke exposure may worsen the health of people with existing heart disease and may trigger a major cardiovascular event even in those without known health conditions,” he said. The contaminated smoke travels many miles beyond the fire zones, reaching areas already experiencing record summer temperatures.
A study published in Circulation, the American Heart Association’s flagship journal, found that the risk of fatal heart attacks nearly doubled during days of extreme heat waves and high levels of fine particle pollution. The risks were even greater for women and older individuals. Additional research has linked smoke exposure to an increased risk of sudden cardiac arrest and a higher volume of emergency room visits for cardiovascular disease-related causes. A study in the Journal of the American Heart Association found that exposure to heavy smoke during wildfires raised the risk of out-of-hospital cardiac arrests up to 70%, with elevated risk among men, women, adults aged 35-64, and communities with lower socioeconomic status.
Previous findings from the same research group noted that wildfire smoke exposure was associated with increased rates of emergency room visits for ischemic heart disease, irregular heart rhythm, heart failure, pulmonary embolism, and stroke.
To reduce risks, Patel recommends staying indoors with doors and windows closed, using high-efficiency air filters in air conditioning systems or portable air cleaners, which can reduce indoor particulate matter by 50-60%, according to the American Heart Association’s 2020 scientific statement on air pollution exposure. If a home lacks air conditioning, seeking alternative shelter is advisable. Limiting outdoor activity, especially between noon and 3 p.m., wearing a mask outdoors, avoiding exertion, staying hydrated with water, and dressing in lightweight, light-colored clothing are also important precautions.
“Protect yourself, be alert and prepared,” Patel said. “It could be the difference in saving your life or that of someone you love.” The American Heart Association provides resources at www.heart.org. The U.S. Environmental Protection Agency offers a zip code-level tracking map of current air quality at airnow.gov.
