Wildfire Smoke and Summer Heat Create Double Threat to Heart Health, American Heart Association Warns

The American Heart Association is alerting the public to the compounded dangers of wildfire smoke and extreme summer heat, which together pose a serious threat to cardiovascular health. As Canadian wildfire smoke drifts into parts of the United States amid record-breaking temperatures, the organization emphasizes that the combination can be deadly, particularly for individuals with existing heart conditions.

“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. He noted that while respiratory issues are often the primary concern with wildfire smoke, the cardiovascular impact is significant and far-reaching. Fine particulate matter in smoke can enter the bloodstream, triggering inflammation and increasing the risk of heart attacks, strokes, and other cardiovascular events.

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 and high levels of fine particle pollution. The risks were even greater for women and older individuals. Another study in the Journal of the American Heart Association reported that exposure to heavy wildfire smoke raised the risk of out-of-hospital cardiac arrests by up to 70%, affecting both men and women, adults aged 35-64, and communities with lower socioeconomic status.

To reduce risks, Patel recommends staying indoors with doors and windows closed, using high-efficiency air filters, and limiting outdoor activity, especially during peak heat hours from noon to 3 p.m. Wearing a mask outdoors, staying hydrated with water, and avoiding alcohol and caffeine are also advised. It is crucial to check on older adults and those with chronic conditions, as they are more vulnerable. Pets should also be brought indoors.

Recognizing the signs of a heart attack or stroke is vital. Symptoms include chest discomfort, shortness of breath, pain in the arms, back, neck, jaw, or stomach, cold sweat, nausea, and lightheadedness. Heat stroke, characterized by a body temperature above 103°F, hot red skin, rapid pulse, confusion, or loss of consciousness, also requires immediate medical attention. Calling 911 and performing CPR can double the chance of survival during cardiac arrest.

The U.S. Environmental Protection Agency offers a zip code-level air quality tracking map at airnow.gov. Patel advises checking this site regularly and staying informed about local health alerts. “Protect yourself, be alert and prepared,” he said. “It could be the difference in saving your life or that of someone you love.”