Air pollution linked to cognitive decline in later years

Shereen Lehman in Reuters Health: The tiny particles in vehicle exhaust and other sources of air pollution may hasten cognitive decline in older adults, according to a new U. S. study. “We decided to examine the link between air pollution and cognitive function in older adults because there is growing evidence that fine particulate matter air pollution affects brain health and development, but relatively little attention has been given to what this means for the aging brain,” said Jennifer Ailshire, who co-wrote the report.

 Ailshire is with the Center for Biodemography and Population Health and the Andrus Gerontology Center at the University of Southern California in Los Angeles. She, along with Philippa Clarke of the Institute for Social Research at the University of Michigan, Ann Arbor, say that based on their results, improvements in air quality may be an important strategy for reducing age-related cognitive decline.

...Routine measurement of air pollution by census tract did not start until the late 1990s, they explain. Cognitive function was measured by math and memory tests and participants got a score based on the number of cognitive errors they made.

...Poverty and other social factors as well as health problems can influence cognitive function, the authors note. And poorer neighborhoods tend to be more polluted. But after the researchers adjusted for education, employment, gender, marital status and several other factors, the differences in cognitive error rates remained.

“The emerging evidence showing a link between air pollution and cognitive function suggests air pollution may harm the brain as well as the heart and lungs,” Ailshire said in an email. “Ideally,” she and Clarke wrote, they would want long-term data and more exact individual pollution exposures to assess the importance of PM2.5 in cognitive function....

Smog over the Louisville, Kentucky, skyline in 1972. From the National Archives