Mortality associated with wildfire smoke exposure in Washington state, 2006-2017: A case-crossover study

Doubleday, A; Schulte, J; Sheppard, L; Kadlec, M; Dhammapala, R; Fox, J; Isaksen, TB

HERO ID

6310032

Reference Type

Journal Article

Year

2020

Language

English

PMID

31931820

HERO ID 6310032
In Press No
Year 2020
Title Mortality associated with wildfire smoke exposure in Washington state, 2006-2017: A case-crossover study
Authors Doubleday, A; Schulte, J; Sheppard, L; Kadlec, M; Dhammapala, R; Fox, J; Isaksen, TB
Journal Environmental Health
Volume 19
Issue 1
Page Numbers 4
Abstract <strong>BACKGROUND: </strong>Wildfire events are increasing in prevalence in the western United States. Research has found mixed results on the degree to which exposure to wildfire smoke is associated with an increased risk of mortality.<br /><br /><strong>METHODS: </strong>We tested for an association between exposure to wildfire smoke and non-traumatic mortality in Washington State, USA. We characterized wildfire smoke days as binary for grid cells based on daily average PM2.5 concentrations, from June 1 through September 30, 2006-2017. Wildfire smoke days were defined as all days with assigned monitor concentration above a PM2.5 value of 20.4 μg/m3, with an additional set of criteria applied to days between 9 and 20.4 μg/m3. We employed a case-crossover study design using conditional logistic regression and time-stratified referent sampling, controlling for humidex.<br /><br /><strong>RESULTS: </strong>The odds of all-ages non-traumatic mortality with same-day exposure was 1.0% (95% CI: - 1.0 - 4.0%) greater on wildfire smoke days compared to non-wildfire smoke days, and the previous day's exposure was associated with a 2.0% (95% CI: 0.0-5.0%) increase. When stratified by cause of mortality, odds of same-day respiratory mortality increased by 9.0% (95% CI: 0.0-18.0%), while the odds of same-day COPD mortality increased by 14.0% (95% CI: 2.0-26.0%). In subgroup analyses, we observed a 35.0% (95% CI: 9.0-67.0%) increase in the odds of same-day respiratory mortality for adults ages 45-64.<br /><br /><strong>CONCLUSIONS: </strong>This study suggests increased odds of mortality in the first few days following wildfire smoke exposure. It is the first to examine this relationship in Washington State and will help inform local and state risk communication efforts and decision-making during future wildfire smoke events.
Doi 10.1186/s12940-020-0559-2
Pmid 31931820
Wosid WOS:000513676600001
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Wildfire; Wildfire smoke; Environmental epidemiology; Mortality