by Prolonged exposure to air pollution increases the risk of depression, according to a pair of new studies published in the JAMA network of scientific journals.
A study published on Friday in open JAMA network found that prolonged exposure to high levels of air pollution increases the risk of late-onset depression among the elderly.
The other study, published in JAMA psychiatryfound that prolonged exposure to low levels of air pollutants was associated with an increased incidence of depression and anxiety.
Air pollution has been linked to cardiovascular and respiratory diseases.
The new studies add to a growing body of evidence that air pollution also affects mental health.
To study the effects of air pollution on older Americans, researchers from Harvard and Emory University examined data from nearly nine million people on Medicare, the US government’s health insurance scheme for people over age 64.
More than 1.52 million of them were diagnosed with depression during the study period from 2005 to 2016, according to Medicare claims.
“We observed statistically significant harmful associations between long-term exposure to high levels of air pollution and increased risk of a late-life diagnosis of depression,” the researchers said.
“Socioeconomically disadvantaged individuals were at a much higher risk of depression in later life in this study,” they said. “They are simultaneously exposed to social stress and poor environmental conditions, including air pollution.”
For the study, researchers mapped pollution levels and compared them to Medicare patients’ addresses.
The pollutants to which they were exposed were fine particulate matter such as dust or smoke, nitrogen dioxide, mainly from traffic emissions, and ozone, emitted by automobiles, power plants and refineries.
The researchers said the elderly may be particularly susceptible to pollution-related depression because of their lung and neural vulnerability.
“Although depression is less prevalent among older adults compared to the younger population, it can have serious consequences such as cognitive impairment, comorbid physical illness, and death,” they said.
In the other study, researchers from Great Britain and China investigated the association of prolonged exposure to various air pollutants and the incidence of depression and anxiety.
They studied a group of nearly 390,000 people, mostly in Britain, over an 11-year period and found that there was an increased risk of depression and anxiety, even at pollution levels below UK air quality standards.
© Agence France-Presse
