Could wildfire smoke increase dementia risk?

A recent study headed by the University of Washington is catching national media attention currently as it points to a connection between exposure to wildfire smoke and dementia in older adults from a large study in California. One new advance is the ability to distinguish between ambient wildfire smoke vs. other types of fine particulate matter (PM2.5) exposure. Although the team’s publication in PubMed is pay-walled (Elser, et al. 2024), you can read a concise description of their work in this November, 2024 Research Highlight by the NIH National Institute on Aging, by Brian Doctrow, PhD. In a nutshell, among 1.2 million Californians aged 60+, there did seem to be a connection between neighborhood wildfire PM2.5 exposure and dementia diagnosis, which was considerably stronger than the connection with other types of fine particulate exposure. For every 1 μg/m3 increase in average wildfire PM2.5, the odds of receiving a dementia diagnosis increased by 18%.

Matsu engine protecting Nenana during the Parks Highway fire, 2006 (Photo: State of Alaska, DNR).