Wildfires have become a common occurrence in the West, posing dangers to lives and property. But a new study published in JAMA Neurology has revealed an overlooked health risk from wildfires.
Research, led by Dr. Joan Casey from the University of Washington School of Public Health and funded by the National Institutes of Health, concludes that fine particulate matter (PM2.5) from wildfires poses a significantly higher risk of dementia compared to PM2.5 from other sources.
The research highlights the growing concern over the health impacts of wildfire smoke, particularly in the Western United States where wildfires are increasingly common.
The study analyzed electronic health records of over 1.2 million members of Kaiser Permanente Southern California, aged 60 and older, who were initially free from dementia. The data, spanning from 2008 to 2019, allowed researchers to estimate PM2.5 concentrations by census tract and differentiate between wildfire-related PM2.5 and that from other sources.
Key findings
Key findings from the study indicated that for every microgram per cubic meter increase in average wildfire PM2.5, the likelihood of a dementia diagnosis rose by 18%. In contrast, the same increase in PM2.5 from other sources was linked to only a 1% increase in dementia risk. This stark difference underscores the unique threat posed by wildfire smoke, the researchers wrote
The research also examined how these risks varied across different demographics. It found that individuals under 75 years old, those living in economically disadvantaged neighborhoods, and certain minority groups, such as Asian and non-Hispanic Black people, experienced a stronger association between wildfire PM2.5 exposure and dementia incidence.
The study suggests that socially and economically disadvantaged groups are particularly vulnerable to the health impacts of wildfire smoke.
Casey said the need for interventions to reduce exposure to wildfire PM2.5 as a means to potentially lower dementia rates and address socioeconomic disparities in health outcomes.
She also highlighted the broader implications of climate change, noting that as global temperatures rise, the frequency and intensity of wildfires are expected to increase, exacerbating the problem.
“It’s a global problem,” Casey said. “While individuals can protect themselves with air filters and masks, we need a global solution to climate change. It’s going to have to be many-pronged—many people have to be involved to solve this highly complex problem.”