A large new study of millions of people shows that exposure to air pollution may be associated with an increased risk. depression at an older age.

Scientists are finding more and more evidence that those who live in areas with high levels of pollution are at greater risk of depression than those who live in areas with cleaner air.

The new study is one of the first to study associations between long-term exposure to poor air quality and risk of depression diagnosed after age 64. Depression in the elderly is associated with mental clarity and physical problems, among other things, and even death.

Previous studies have shown that older people are less likely to be diagnosed with depression than younger people. “This is one of the main reasons we wanted to do this analysis,” explained Dr. Xinye Qiu, one of the authors of the new study, published today in JAMA Network Open. Qiu is a postdoctoral fellow in the Department of Environmental Health at the Harvard Harvard School of Public Health. T. H. Chan. “Surprisingly, in this study, we found a large number of late-onset depression diagnoses,” he says.