203 Your pores and the outdoors: Investigating the association between pollution and inflammatory dermatological diseases

Particulate Matter 2.5 (PM 2.5) is a type of pollutant ∼20 times smaller than human pores. Recent in-vitro and in-vivo studies have linked exposure to PM 2.5 to a variety of dermatologic conditions including atopic dermatitis, alopecia, and skin cancer. However, population based studies remain limited. This study investigates the association between PM 2.5 and 3 inflammatory conditions: atopic dermatitis (AD), hidradenitis suppurativa (HS) and psoriasis. We compared average PM 2.5 levels to Google Trends Search Volume Index (SVI) in U.S. states; SVI served as a proxy for disease prevalence. As a negative control, we compared CO2 concentrations by state to Google Trends SVI for all 3 conditions. After adjusting for precipitation, temperature, percentage of the population living in an urban environment, and density for each state, all 3 conditions had significant associations with PM 2.5 levels: AD (R2 = 0.41, p=0.0004); HS (R2 = 0.29, p=0.011); and psoriasis (R2 = 0.27, p=0.018). All 3 conditions did not have significant associations with CO2: AD (R2 = 0.02, p=0.36); HS (R2 = 0.0001, p=0.95); and psoriasis (R2 = 0.004, p=0.66). These novel findings contribute to our understanding of the pathogenesis of these inflammatory conditions. Further research is needed to quantitatively characterize the impact of air pollution on the prevalence or severity of these conditions. As air pollution rises globally, elucidating its role in the pathogenesis and exacerbation of these diseases is critical in order for clinicians to better care for their patients with these conditions.