Characterizing Impacts of Wildfire Smoke Exposure on Medication Fills and Outpatient Visits for Asthma during the 2015 Wildfire Season in the Western United States
Year: 2019
Type: conference-abstract
Abstract: OPS 10: Wildfires, Room 210, Floor 2, August 26, 2019, 10:30 AM - 12:00 PM Background/Aim: Smoke from wildfires impacted several states in the western United States (U.S.) during the summer months of 2015. Our objective was to evaluate associations between smoke-related fine particulate matter (smoke PM2.5) concentrations and adverse health outcomes for asthma, specifically medication fills and outpatient visits, using spatio-temporal exposure models and epidemiological regression techniques. Methods: Our assessment examined employer-based health insurance claims for asthma from the Truven-IBM health insurance claims database for a period between June 1st and September 30th, 2015, covering 11 states in the western U.S. We linked approximately 450,000 asthma medication fills and 85,000 outpatient visit records with smoke concentrations estimated from a geographically weighted ridge regression (GWR) model. The GWR model blends information from PM2.5 monitors, a chemical-weather model, and satellite data products to estimate PM2.5 concentrations in the smoke-affected area. A conditional quasi-Poisson regression with month/day/place strata in combination with a distributed lag non-linear model, was used to measure the overall cumulative effect of smoke concentrations. This regression framework explored how the associations were distributed over a 7-day lag period and included predictors, such as cross-basis terms for daily measures of ozone, relative humidity, and temperature. Results: The estimated (95% Confidence Interval) risk ratios (RRs) associated with a 10 µg/m3 increase in smoke PM2.5 exposure for asthma medication refills and outpatient visits were 1.072 (1.052 – 1.093) and 1.109 (1.065 – 1.153), respectively. RRs estimated on the day of smoke exposure were the highest, but delayed effects of smoke on these health outcomes were statistically significant and persisted until 5 days following the smoke exposure. Conclusions Asthma medication refills and outpatient visits are significantly associated with smoke PM2.5. A comprehensive strategy to mitigate adverse health impacts associated with wildfire disasters necessitates a thorough understanding of population-level exposures and health impacts associated with smoke PM2.5 concentrations.
Source: Environmental Epidemiology
Authors: Vaidyanathan A, Vicedo-Cabrera A, O’Dell K, Ford B, Gan R, Saha S, Magzamen S, Gasparrini A, Pierce J
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,200
OpenAlex ID: W2982011697