How wildfires may lead to higher rates of dementia

As a record number of baby boomers turn 65, the percentage of Americans living with some form of mental decline– severe enough to interfere with daily living – is expected to rise.

What exactly leads to dementia is still something of a mystery - but lifestyle and environmental factors are known to contribute to a person’s risk of cognitive decline.

A study published last week in the Journal of the American Medical Association Neurology identifies a new factor that may be impacting dementia risk: wildfire smoke.

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Guest:

• Joan Casey is the lead author of the newly published study “Wildfire Smoke Exposure and Incident Dementia”, she’s also an associate professor of environmental & occupational health sciences at the University of Washington

Relevant Links:

• Video: UW-led research links wildfire smoke exposure with increased dementia risk - UW News
• Wildfire Smoke Exposure and Incident Dementia - JAMA Neurology

Correction notice, Monday 07/07/2025 at 2:30 p.m.: We have removed this interview from the website because the study it discussed has been retracted by the authors after they discovered a coding error. You can read the researchers' full explanation in this retraction notice.

The retracted study has been replaced by an article in JAMA Neurology that reads, in part, “…(W)e did not observe a statistically significant association between long-term exposure to wildfire fine particulate matter (PM2.5) and dementia diagnosis, although an association was seen among those less than 75 years of age at cohort entry and among a subset of members who reported their race and ethnicity as multiple races, Native American and Alaskan Native, Pacific Islander, other, and unknown race and ethnicity.”