Wildfire Smoke Exposure Linked to HF Risk

Increased exposure to fine particulate matter from wildfire smoke was associated with an increased risk for heart failure compared with exposure to other types of smoke particulate matter, according to the results of a recent study in JACC.

A retrospective study analyzed data from approximately 22 million Medicare beneficiaries and used predictions from a wildfire particulate matter model to compare exposure and risk of those from ZIP codes with high-resolution exposure to fire smoke particles less than 2.5 μm in diameter (PM_2.5) and those exposed to nonfire smoke PM_2.5.

Overall, the mean smoke PM_2.5 exposure, calculated as the average of all past 2-year moving average exposures across person-years, was 0.51 μg/m³.

Each 1 μg/m³ in that average was associated with a hazard ratio for heart failure of 1.014, “notably higher” than that of those with nonsmoke PM_2.5 exposure (HR=1.005). The researchers wrote that the association corresponded to an estimated 20,238 (95% CI: 10,727-29,612) additional heart failure cases annually among US older adults.”

In other words, the researchers determined that wildfire smoke was associated with a 1.4% increased risk for heart failure, whereas the heart failure risk for the same level of exposure to non-smoke sources increased just 0.5%.

The researchers also identified a greater susceptibility in women and socially vulnerable populations, such as those who are eligible for Medicaid, and those living in lower-income areas.

“This study highlights a growing and underappreciated threat to heart health. As wildfire smoke becomes more frequent and intense, we are learning that even small, long-term exposures can raise the risk of heart failure, especially among the most vulnerable. These findings elevate the urgency of protecting communities through both environmental policy and health care preparedness,” Harlan M. Krumholz, MD, Harold H. Hines Jr. Professor at Yale School of Medicine and editor-in-chief of JACC, said in a release.