Short-term exposure to traffic-related air pollutants (i.e., particular matter_2.5 [PM_2.5], nitrogen dioxide [NO₂], and sulfur dioxide [SO₂]) was linked with a risk of dry eye disease (DED) outpatient visits, according to a recent study in BMC Public Health.

A total of 27,828 DED cases were identified during the study period, including 2557 days. The daily number of outpatient visits for DED ranged from 0 to 41. The study shows that an increase of 10 μg/m3 in PM2.5, NO2, and SO2 concentration was linked with a 3.1%, 5.9%, and 17.4% increase in the risk of DED outpatient visits, respectively.

Additionally, a subgroup assessment (stratified by age, gender, and season) indicated that the effects of PM_2.5 and SO₂ exposure on the risk of DED outpatient visits stayed significant in patients younger than age 60; and in female patients, respectively.

Further, PM2.5 and SO2 exposure associations with DED outpatient visits risk stayed significant during warm seasons, while NO₂ exposure was significantly linked with DED outpatient visits in cold seasons.

Finally, associations of PM_2.5, NO₂, and SO₂ exposure with risk of DED outpatient visits were significant for both first- and re-visits.

The study researchers reached these conclusions after collecting daily data on DED outpatient visits and environmental variables from Jan. 1, 2014, to Dec. 31, 2020, in Guangzhou, a city in South China.