Effects of Wildfire Exposure on Markers of Accelerated Brain Aging and Dementia Risk

The Los Angeles wildfires that began in January 2025 have led to a recent excess in adverse health outcomes, as seen following prior major urban disasters. A broad range of chronic disease conditions is expected to continue rising in the wake of the wildfire disaster. Among the most functionally impactful of these conditions is neurocognitive disease. Prior studies indicate that especially highly exposed individuals will suffer substantial risks for early-onset cognitive impairment and overt dementia. However, the mechanistic triggers and drivers of this neuropathology remain unclear. Importantly, the Los Angeles fires occurred across broad areas of wildland- urban interface, where the burning of both natural and synthetic fuels has generated a complex aggregate of chemical products that include volatile organic compounds such as benzene and related derivatives as well as semi-volatile organic compounds such as perfluorochemicals, all of which have been associated with neurodegenerative pathology. Therefore, we hypothesize that in the aftermath of the Los Angeles wildfires, a large population of exposed individuals is now at risk for accelerated neurocognitive disease. We postulate that any discernible neuropathology will correspond with detectable blood levels of wildfire related chemical compounds that will be acutely and then chronically elevated in certain individuals. Thus, we propose to conduct a time-sensitive prospective cohort study that will involve tracking newly appearing or rising blood levels of chemical products of combustion, biomarkers of neuroinflammation and neuropathology, and serial assessments of neurocognitive function and neurodegeneration. We anticipate the results of this study will provide urgently needed scientific evidence regarding the adverse neurocognitive health effects triggered by recent wildfire exposures, along with insights into mechanistic determinants that will aid in developing strategies for mitigating the ongoing and longer-term harms from this unprecedented disaster. Project Number: 1R01AG099094-01 | Fiscal Year: 2026 | NIH Institute/Center: National Institute on Aging (NIA) | Principal Investigator: Susan Cheng (+1 co-PI) | Institution: CEDARS-SINAI MEDICAL CENTER, LOS ANGELES, CA | Award Amount: $701,073 | Activity Code: R01 | Study Section: Social and Environmental Determinants of Health Study Section[SEDH] View on NIH RePORTER: https://reporter.nih.gov/project-details/11308584