Impact of Particulate Matter Exposure on Neurological Health in Older Adults: A Systematic Review.
Mateusz Zaręba, Damian Pietrzak, Agata Stolecka et al.
✦ AI-curated · Sources linked
In 30 seconds
This PRISMA-guided systematic review assessed epidemiological evidence linking particulate matter (PM) exposure with neurological health in older adults. It included 21 observational studies identified through searches conducted through January 2026. The most substantial evidence concerned long-term PM2.5 exposure and cognitive outcomes, including cognitive performance and decline and cognitive impairment; several studies reported adverse associations. Evidence relating PM exposure to dementia and Alzheimer’s disease was also available, but findings varied by exposure measure and clinical endpoint. Evidence for other neurological outcomes and specific PM constituents was more limited. The review found no single pooled quantitative effect estimate.
Key findings
- Among 21 observational studies, the strongest body of evidence concerned long-term PM2.5 exposure and cognitive outcomes.
- Several studies reported adverse associations between PM exposure and cognitive performance or decline and cognitive impairment, including mild cognitive impairment.
- Evidence for dementia and Alzheimer’s disease came from several large cohort studies, but results varied across exposure metrics and clinical endpoints.
- Evidence for other outcomes and individual PM constituents was limited, often based on one or a few studies, and heterogeneous.
Why it matters
The review brings together evidence relevant to a potentially important environmental exposure in older adults, for whom cognitive decline and neurodegenerative disease are consequential outcomes. Its findings support attention to long-term PM2.5 exposure in research on neurological health, while the variation in study methods and results means that associations should not be interpreted as proof of causation or as equally established across outcomes.
What to keep in mind
The evidence came from observational studies, with heterogeneity in study design, exposure assessment, and outcome definitions. Evidence was limited for several neurological endpoints and individual PM constituents.