High Anxiety May Be Linked to Air Pollution

HealthDay News — Mental well-being as well as physical health could be negatively impacted by air pollution, findings from two separate studies published in The BMJ indicate.

“Recent evidence suggests a role in diverse outcomes, including diabetes, low birth weight, and preterm birth. This research stems from improved understanding of the role of air pollution in initiating systemic inflammation, a response that may affect multiple organ systems,” noted Michael Brauer, ScD, of the University of British Columbia in Vancouver, in an accompanying editorial3.

In the first study1, Anoop S.V. Shah, MD, of the University of Edinburgh, in the United Kingdom, and colleagues conducted a systematic review and meta-analysis of 103 observational studies to review evidence for the short term association between air pollution and stroke. There was a “clear association” between air pollution and people’s short-term risk of having or dying from a stroke, overall, reported the scientists.

In a separate study2, Melinda C. Power, ScD, of Harvard University in Boston, and colleagues sought to determine whether higher past exposure to particulate air pollution is associated with prevalent high symptoms of anxiety.

“Given the substantial personal and societal burden from anxiety and the problem of treatment resistance, it is imperative to identify modifiable risk factors for anxiety disorders and symptoms,” wrote the researchers.

“One important environmental exposure that may be related to anxiety is air pollution.”

The investigators followed female patients (n=71,271), aged 57 to 85 years, who were enrolled in the Nurses’ Health Study residing throughout the contiguous United States. The participants had valid estimates on exposure to particulate matter for at least one exposure period of interest and data on anxiety symptoms.

The women were asked some standard questions about anxiety symptoms — looking at whether they had certain phobias or tended to be worriers in general. Overall, 15% showed “high symptoms” of anxiety. The researchers then estimated the women’s exposure to air pollution based on where they lived.

In general, the study found, the women’s risk of anxiety symptoms increased along with their exposure to fine particle pollution. Those particles are released into the air when fossil fuels are burned, so car exhaust and industrial sources, such as power plants, are big contributors.

“The findings of these two studies support a sharper focus on air pollution as a leading global health concern,” noted Brauer in the editorial.

“While this is a primary reason for the large disease burden attributable to outdoor air pollution, it also follows that even modest reductions in pollution could have widespread benefits throughout populations.”


  1. Shah ASV, et al. Short term exposure to air pollution and stroke: systematic review and meta-analysis. BMJ. 2015; doi: http://dx.doi.org/10.1136/bmj.h1295.
  2. Power MC, et al. The relation between past exposure to fine particulate air pollution and prevalent anxiety: observational cohort study. BMJ. 2015; doi: http://dx.doi.org/10.1136/bmj.h1111.
  3. Brauer M. Air pollution, stroke and anxiety. BMJ. 2015; doi: http://dx.doi.org/10.1136/bmj.h1510.