Association between Air Quality Index and the risk of rosacea: A Nationwide population-based Cohort Study.

BACKGROUND: Air pollution is associated with several inflammatory skin disorders. However, the association between air quality and rosacea remains unclear.

OBJECTIVE: To investigate the association between air quality index and incidence of rosacea.

METHODS: Overall, 21,709,479 participants without rosacea before 2008 were recruited from the Taiwan National Health Insurance Research Database. The long-term average air quality index (AQI) value for each participant was acquired from the Taiwan Air Quality Monitoring System Network and calculated from 2008/1/1 until the diagnosis of rosacea, withdrawal from the National Health Insurance, or December 31, 2018.

RESULTS: We observed a significant association between AQI and the incidence of rosacea, with each unit elevation in AQI increasing the risk of rosacea by 5 %. Compared with the Q1 group, the Q2, Q3, and Q4 cohorts exhibited 1.82-fold, 4.48-fold and 7.22-fold increased risk of rosacea, respectively. Additionally, exposure to PM2.5, SO2 and CO increased the risk of rosacea, whereas exposure to PM10 was associated with a lower risk.

CONCLUSION: This study supported a significant dose-response relationship between AQI and the incidence of rosacea.