Air pollution exposure may be associated with eczema

The prevalence of eczema has increased globally with industrialization, suggesting a possible contribution from environmental factors. In the new study, researchers used data from the U.S. National Institutes of Health All of Us Research Program, covering hundreds of thousands of U.S. adults. The current study included 286,862 people for whom there was available demographic, zip code and electronic health record data.

Overall, 12,695 participants (4.4%) were diagnosed with eczema. After controlling for demographics and smoking status, people with eczema were more likely to live in zip codes with high levels of fine particulate matter, or PM_2.5, in the air. For every increase of 10 µm/m³ in average PM_2.5 air pollution in their zip code, people were more than twice as likely to have eczema.

The authors conclude that increased air pollution, as measured by PM_2.5, may influence the risk of developing eczema, likely through its effects on the immune system.

The authors add: "Showing that individuals in the United States who are exposed to particulate matter are more likely to have eczema deepens our understanding of the important health implications of ambient air pollution."