Short-term exposure to ambient fine particulate matter and psoriasis: A time-series analysis in Beijing, China

BACKGROUND: Ambient fine particulate matter (PM(2.5)) adversely affects human health and has been linked to a variety of skin disorders. However, little is known about the effects of PM(2.5) on psoriasis. METHODS: The Beijing Medical Claim Data for Employees database recorded 500,266 outpatient visits for psoriasis during 2010–2017. A generalized additive quasi-Poisson model was used to examine the relationship between daily PM(2.5) concentrations and outpatient visits for psoriasis with stratification by sex, age, and season. RESULTS: Short-term exposure to PM(2.5) was associated with outpatient visits for psoriasis-related health concerns. A same-day increase of 10 μg/m(3) in PM(2.5) concentrations was associated with a 0.29% (95% confidence interval: 0.26–0.32%) increase in daily outpatient visits for psoriasis. Female and older patients appeared to be more sensitive to the effects of PM(2.5) (P < 0.05). CONCLUSIONS: Short-term elevations in PM(2.5) concentrations may be associated with exacerbations in psoriasis. Further work is warranted to confirm the findings and elucidate the underlying biological mechanisms.