Daaniya Iyaz

Project title: Impact of Wildfire Smoke Events on Seattle Children’s Pediatric Patient Outcomes, 2006 - 2020

Degree: MS (Thesis) | Program: Environmental Health (EH) | Project type: Thesis/Dissertation
Completed in: 2022 | Faculty advisor: Tania M Busch Isaksen


Pacific Northwest wildfire smoke events have been increasing in prevalence and severity over the past three decades, resulting in documented negative health outcomes in adults. However, when examining the effect of wildfire smoke on pediatric health, the literature is scarce. We utilized a case crossover study to determine the odds of pediatric emergency department (ED) visits and hospital admission at Seattle Children’s Hospital on smoke days versus non-smoke days during wildfire season (June to September) from 2006 to 2020. Our analysis used a conditional logistic regression model that controls for temperature and relative humidity to evaluate the association between daily average PM2.5 concentrations and pediatric hospital encounters for all causes and specific conditions. The results indicate a 0.0% (95% CI: -3.0% - 3.0%) change in odds for all-cause same-day emergency department (ED) visits on wildfire smoke days versus non-wildfire smoke days when controlling for Humidex and a 7.0% (95% CI: 3.0% – 12.0%) increase in odds for all-cause inpatient/observational hospital admissions. When stratifying by health outcomes, we found a 9.0% (95% CI: 1.0% – 17.0%) and a 11.0% (95% CI: 1.0% – 21.0%) increase in odds for being admitted to the ER for a respiratory and respiratory infection-related concern, respectively. We also observed statistically significant increases for inpatient/observational admissions odds, ranging from 5.0% - 8.0%, for lagged exposure on days 1 – 4 when using lag models that adjusted for Humidex. When evaluating inpatient/observational cases, we found a 44.0% (95% CI: 3.0% – 102.0%) increase in odds for trauma-related cases. Our findings add to the current understanding by observing increased odds of respiratory-related ED visits and all-cause hospital admissions for Seattle Children’s patients on smoke days versus non-smoke days when adjusting for Humidex. The risk remained elevated with exposure to wildfire smoke up to 4 days prior to inpatient and observational hospital admission.

URI: http://hdl.handle.net/1773/48966