395 Wildfire air pollution and increased online search interest and clinic visits for psoriasis

Wildfires are increasingly contributing to worsening air pollution. During California wildfires, clinic visits and online search interest for atopic dermatitis and itch increased, but not for psoriasis. We assessed whether clinic visits and search interest for psoriasis were associated with wildfire air pollution after a delayed lag period. A cross-sectional time-series study was done using three metrics for air pollution: fire status, particulate matter (PM2.5), and smoke plume density. Data were collected for outpatient dermatology visits at an academic medical center in San Francisco from Oct. 2018-Feb. 2019 (including the California Camp Fire), Oct. 2015-Feb. 2016 (no fires), and Oct. 2016-Feb. 2017 (no fires). Data on psoriasis clinic visits were stratified by age group and analyzed by generalized Poisson regression. Statistical models were adjusted for temperature, humidity, age, year, and overall patient volume at clinics. Weekly online search volume interest (SVI) for 2018 in San Francisco was collected, for the term “psoriasis” from Google Trends. We analyzed 986 visits for psoriasis. An increase in adult visits occurred at week 5 after the fire [RR: 1.32 (95% CI: 1.02-1.70)] and peaked at week 8 [RR: 1.45 (95% CI: 1.13-1.86)] and week 9 [RR: 1.45 (95% CI: 1.12-1.87)]. No significant results were found for pediatric patients, likely due to limited patient numbers. Mean weekly SVI for psoriasis showed an increase starting 5 weeks after the fire, peaking at week 8. Wildfire air pollution was associated with a delayed increase in SVI and clinic visits for psoriasis.