Air pollution exposure may increase risk of depression in elderly people

February 15, 2023—Long-term exposure to air pollution may lead to higher risk of depression later in life, according to a new study led by Harvard T.H. Chan School of Public Health.

The study was published in JAMA Network Open on February 10. Co-authors included Xinye Qiu and Yaguang Wei, postdoctoral research fellows in the Department of Environmental Health; Laura Kubzansky, professor of social and behavioral sciences and director of the Society and Health Laboratory; Edgar Castro, doctoral student in the Department of Environmental Health; Marc Weisskopf, professor of environmental epidemiology and physiology; and Joel Schwartz, professor of environmental epidemiology.

Little research has been conducted about air pollution and mental health conditions among senior citizens. To fill this gap, the researchers studied the health claims of more than 8.9 million people older than 64 and enrolled in Medicare, then zeroed in on diagnoses of depression and average yearly exposure to air pollutants based on zip code.

What the study found—a significant association between depression and exposure to air pollution, even at lower levels—has “implications for both environmental regulation and public health management,” the researchers wrote.

In a February 10 CNN article, Qiu noted the urgency of addressing the intersection between climate change, which increases air pollution, and mental health among older people.

“Late-life depression should be a geriatric issue that the public and researchers need to be paying more attention to, like on a similar level with Alzheimer’s and other neurological conditions,” she said. “There’s no real threshold [for exposure to air pollution], so it means future societies will want to eliminate this pollution or reduce it as much as possible because it carries a real risk.”

In related news, another recent study from researchers in China and the United Kingdom found links between air pollution and risk for mental health conditions like depression and anxiety. A February 6 USA Today article shared tips on how people can reduce their exposure to air pollution—with cautionary context provided by Weisskopf.

“You can try and limit it to some degree,” Weisskopf said. “But it’s the kind of thing at the population level that really needs regulatory action.”

Read the Harvard Chan School study: Association of Long-term Exposure to Air Pollution With Late-Life Depression in Older Adults in the US

Read the CNN article: Long-term exposure to air pollution may raise risk of depression later in life, study says

Read the USA Today article: Exposure to air pollution increases risk for anxiety or depression. What can you do?