Exposure to air pollution ups risk of atopic dermatitis

Long-term exposure to air pollutants, including gases and particulate matter, may increase the risk of developing atopic dermatitis (AD), according to a recent study.

“To date, little evidence is available to determine whether AD can be caused by exposure to air pollutants, including gases and particulate matter,” said the authors, who then conducted this study to assess the relationship between air pollutants and incidence of AD using the National Health Insurance Service-National Sample Cohort database.

A total of 209,168 individuals from the general population who were not previously diagnosed with AD between 2008 and 2013 were included in the analysis. The authors calculated the long-term average concentration of air pollutants before diagnosis for each participant.

Of the participants, 3,203 developed AD over 1,030,324 person-years of follow-up.

After adjustments for age, sex, income, comorbid diseases, and meteorologic variables, a significant association was seen between incidence of AD and long-term average concentration of particulate matter smaller than 2.5 μm in diameter (hazard ratio [HR], 1.420, 95 percent confidence interval [CI], 1.392‒1.448; for 1 μg/m³), particulate matter smaller than 10 μm in diameter (HR, 1.333, 95 percent CI, 1.325‒1.341; for 1 μg/m³), sulfur dioxide (HR, 1.626, 95 percent CI, 1.559‒1.695; for 1 parts per billion), nitrogen dioxide (HR, 1.200, 95 percent CI, 1.187‒1.212; for 1 parts per billion), and carbon monoxide (HR, 1.005, 95 percent CI, 1.004‒1.005; for 1 parts per billion).

One limitation of this study was that the National Health Insurance Service database lacked detailed information on each participant.