A new study led by University College London (UCL) researchers has revealed that prolonged exposure to high levels of air pollution may negatively impact brain health in older adults in England. The findings, published in The Journals of Gerontology, Series A, indicate a clear association between pollutants such as nitrogen dioxide (NO2) and fine particulate matter (PM2.5) and diminished cognitive abilities, particularly in language skills.
The research highlights that NO2, which primarily comes from vehicle emissions, power plants, and industrial machinery, and PM2.5, which originates from the burning of fuels like gasoline, oil, and wood, can deeply affect cognitive function. These pollutants are small enough to be inhaled into the lungs, potentially reaching the brain.
Researchers analyzed data from 1,127 adults aged 65 and older who participated in the 2018 ELSA Harmonized Cognitive Assessment Protocol (ELSA-HCAP). The study examined their exposure to air pollution over a period of 8-10 years (2008-2017) and assessed their memory, executive function, language, and overall cognitive abilities.
Participants underwent a series of standard neurocognitive tests, including the “East Boston Memory Test” and the “Wechsler Memory Scale,” along with tasks designed to evaluate recall and problem-solving abilities. The results showed that individuals living in areas with the highest levels of NO2 and PM2.5 scored significantly lower on cognitive assessments, particularly in language-related tasks.
The study found that the most pronounced impact of air pollution was on language skills, with individuals in the most polluted areas performing in the lowest third of cognitive tests. This suggests that specific pollutants may have a targeted effect on certain cognitive functions, with language fluency being particularly vulnerable.
Further analysis revealed that different sources of pollution have varying effects on cognitive health. For instance, pollutants from industrial activities, home heating, and the combustion of fuels such as coal and oil were strongly linked to poorer performance in language tasks, especially word recall and fluency.
Although the researchers did not investigate the underlying causes of these findings, they hypothesize that increased exposure to air pollution may impair the temporal lobe, the brain region responsible for language processing and semantic fluency. The authors call for additional research to explore these connections further.
Dr. Giorgio Di Gessa, lead author of the study and a researcher at UCL’s Epidemiology & Health department, emphasized the broader health risks of air pollution. “Our study shows that air pollution is not just harmful to the lungs and heart but also to brain health, particularly when exposure occurs over long periods. The strongest links we found were with language ability, which could suggest that certain pollutants have specific effects on particular cognitive processes.”
The study’s findings also prompted calls for stronger air quality regulations. Professor Paola Zaninotto, deputy director of the ELSA study, stated, “By tracking pollution levels over a decade with high-quality data, our research provides solid evidence that long-term exposure to pollutants damages brain function, making it crucial for policymakers to act.”
Despite the study’s significant implications, there are some limitations. The research only considered a 10-year period of air pollution data, which may not fully represent lifelong exposure. Additionally, the study used annual averages of pollution levels, which do not account for short-term spikes in pollution. Furthermore, the study’s sample size was limited to England, which may not reflect broader trends in other regions.
As research on this topic continues, experts stress the need for greater attention to the long-term health effects of air pollution on older adults.
Related topics:
Weight Training Shown to Protect the Brain Against Dementia, Study Finds
Low LDL Cholesterol Linked to Reduced Dementia Risk, Study Finds
AF Linked to Higher Dementia Risk in Younger Patients
