THURSDAY, Feb. 5, 2026 (HealthDay News) -- Exposure to wildfire smoke fine particulate matter (PM2.5) is associated with an increased risk for incident stroke among older adults, according to a study published online Jan. 27 in the European Heart Journal.Hua Hao, Ph.D., from the Rollins School of Public Health at Emory University in Atlanta, and colleagues examined the association between long-term wildfire smoke PM2.5 exposure and incident stroke among older U.S. adults (65 years and older) in a national open cohort study. Hazard ratios were estimated per 1 µg/m3 increase in wildfire smoke PM2.5, adjusting for nonsmoke PM2.5, meteorologic variables, socioeconomic status, and health care capacity.There were about 2.9 million incident stroke cases among about 25 million beneficiaries. The researchers found a significant association for long-term wildfire smoke PM2.5 exposure with increased stroke risk. The associations were stronger for longer exposure windows; for example, there was a 1.3 percent increase in stroke risk per 1 µg/m3 increase in three-year average wildfire smoke PM2.5 (hazard ratio, 1.013). Per unit exposure, associations for wildfire smoke PM2.5 were generally stronger than for nonsmoke PM2.5."For people living in fire-prone areas, it is important to understand that wildfire smoke is not only an immediate breathing hazard, it may also raise long-term stroke risk," lead author Yang Liu, Ph.D., also from the Rollins School of Public Health, said in a statement. "Preventative behaviors, like turning on indoor air filtration and limiting outdoor exertion on heavy smoke days, are not just about comfort, they may help prevent a stroke."Abstract/Full TextEditorial.Sign up for our weekly HealthDay newsletter