Living in areas with a lot of air pollution can lead to decreased cognitive function in older adults, according to new research presented at The Gerontological Society of America’s (GSA) 65th Annual Scientific Meeting.
“As a result of age-related declines in health and functioning, older adults are particularly vulnerable to the hazards of exposure to unhealthy air,” said Jennifer Ailshire, Ph.D., a National Institute on Aging postdoctoral fellow at the University of Southern California.
“Air pollution has been linked to increased cardiovascular and respiratory problems, and even premature death, in older populations, and there is emerging evidence that exposure to particulate air pollution may have adverse effects on brain health and functioning as well.”
Her study, based on data from the U.S. Environmental Protection Agency and the 2004 Health and Retirement Study, suggests that fine air particulate matter may be an important environmental risk factor for reduced cognitive function.
Fine air particulate matter is composed of particles that are 2.5 micrometers in diameter and smaller. These particles are thought to be so small that if inhaled they can deposit deep in the lung and possibly the brain.
Ailshire analyzed data on 14,793 white, black, and Hispanic men and women aged 50 and older who participated in the 2004 Health and Retirement Study. That data was linked with data on 2004 annual average levels of fine air particulate matter from the EPA’s Air Quality System monitors across the country.
Cognitive function was measured on a scale of 1 to 35 and consisted of tests assessing word recall, knowledge, language, and orientation.
Ailshire discovered that those living in areas with high levels of fine air particulate matter scored poorer on the cognitive function tests.
The association even remained after accounting for several factors, including age, race/ethnicity, education, smoking behavior, and respiratory and cardiovascular conditions, she said.
Fine air particulate matter exposures ranged from 4.1 to 20.7 micrograms per cubic meter, and every 10 point increase was associated with a 0.36 point drop in cognitive function score, according to the researcher.
This effect was roughly equal to aging three years, she added, noting that among all study subjects, a one-year increase in age was associated with a 0.13 drop in cognitive function score.