Open AccessComparison of wildfire smoke estimation methods and associations with cardiopulmonary‐related hospital admissions
Author(s) -
Gan Ryan W.,
Ford Bonne,
Lassman William,
Pfister Gabriele,
Vaidyanathan Ambarish,
Fischer Emily,
Volckens John,
Pierce Jeffrey R.,
Magzamen Sheryl
Publication year - 2017
Publication title -
geohealth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 12
ISSN - 2471-1403
DOI - 10.1002/2017gh000073
Subject(s) - confidence interval , smoke , copd , odds ratio , environmental science , particulates , weather research and forecasting model , medicine , population , atmospheric sciences , meteorology , environmental health , aerosol , geography , ecology , geology , biology
Climate forecasts predict an increase in frequency and intensity of wildfires. Associations between health outcomes and population exposure to smoke from Washington 2012 wildfires were compared using surface monitors, chemical‐weather models, and a novel method blending three exposure information sources. The association between smoke particulate matter ≤2.5 μm in diameter (PM 2.5 ) and cardiopulmonary hospital admissions occurring in Washington from 1 July to 31 October 2012 was evaluated using a time‐stratified case‐crossover design. Hospital admissions aggregated by ZIP code were linked with population‐weighted daily average concentrations of smoke PM 2.5 estimated using three distinct methods: a simulation with the Weather Research and Forecasting with Chemistry (WRF‐Chem) model, a kriged interpolation of PM 2.5 measurements from surface monitors, and a geographically weighted ridge regression (GWR) that blended inputs from WRF‐Chem, satellite observations of aerosol optical depth, and kriged PM 2.5 . A 10 μg/m 3 increase in GWR smoke PM 2.5 was associated with an 8% increased risk in asthma‐related hospital admissions (odds ratio (OR): 1.076, 95% confidence interval (CI): 1.019–1.136); other smoke estimation methods yielded similar results. However, point estimates for chronic obstructive pulmonary disease (COPD) differed by smoke PM 2.5 exposure method: a 10 μg/m 3 increase using GWR was significantly associated with increased risk of COPD (OR: 1.084, 95%CI: 1.026–1.145) and not significant using WRF‐Chem (OR: 0.986, 95%CI: 0.931–1.045). The magnitude (OR) and uncertainty (95%CI) of associations between smoke PM 2.5 and hospital admissions were dependent on estimation method used and outcome evaluated. Choice of smoke exposure estimation method used can impact the overall conclusion of the study.