Air pollution increases anxiety risk
Exposure to particulate matter could induce or exacerbate anxiety through increased oxidative stress and inflammation or through inducing or aggravating pre-existing medical conditions
According to the Anxiety and Depression Association of America, anxiety disorders affect 40 million adults in the United States, making these disorders the most common mental illness. It’s estimated that these disorders cost more than US$42bn a year. What’s more, in nearly 50% of individuals diagnosed with anxiety, they also suffer with depression.
These disorders can be difficult to treat because pharmaceutical drugs are inconsistent and come with side-effects that affect compliance. That’s why it’s so important to identifying modifiable risk factors. One risk factor that clinicians may not be considering with this patient population is anxiety.
A 2015 cohort study that was a part of the Nurses’ Health Study set out to determine the connection between exposure to fine particulate air pollution and anxiety. More than 71,000 nurses age 57 to 85 living in 11 states were followed from 1988 to 2007. Proximity to major roadways was established and monthly exposure to particulate matter was measured using spatiotemporal prediction models. Anxiety symptoms were measured using the Crown-Crisp index phobic anxiety scale.
The researchers found that nurses who lived less than 200 miles from the nearest major road were more likely to have higher phobic anxiety scores than nurses who lived more than 200 miles from these roads. There was a significant increase in anxiety in nurses who were exposed to higher levels of fine particulate matter, specifically less than 2.5µm in diameter. This is the particulate size of air pollution that results in reduced visibility and causes the air to become hazy. The smaller particulate size has greater lung penetrability and may, therefore, more readily disperse systemically.
Exposure to particulate matter could induce or exacerbate anxiety through increased oxidative stress and inflammation or through inducing or aggravating pre-existing medical conditions. Using a quality home air filter and avoiding the outdoors when air pollution is high may also be prudent advice, especially with individuals who are diagnosed with an anxiety disorder or at risk of developing anxiety.
