The relationship of respiratory and cardiovascular hospital admissions to the southern California wildfires of 2003

Delfino, RJ; Brummel, S; Wu, J; Stern, H; Ostro, B; Lipsett, M; Winer, A; Street, DH; Zhang, L; Tjoa, T; Gillen, DL

HERO ID

191994

Reference Type

Journal Article

Year

2009

Language

English

PMID

19017694

HERO ID 191994
In Press No
Year 2009
Title The relationship of respiratory and cardiovascular hospital admissions to the southern California wildfires of 2003
Authors Delfino, RJ; Brummel, S; Wu, J; Stern, H; Ostro, B; Lipsett, M; Winer, A; Street, DH; Zhang, L; Tjoa, T; Gillen, DL
Journal Occupational and Environmental Medicine
Volume 66
Issue 3
Page Numbers 189-197
Abstract Objective: There is limited information on the public health impact of wildfires. The relationship of cardiorespiratory hospital admissions (n = 40 856) to wildfire-related particulate matter (PM2.5) during catastrophic wildfires in southern California in October 2003 was evaluated. Methods: Zip code level PM2.5 concentrations were estimated using spatial interpolations from measured PM2.5, light extinction, meteorological conditions, and smoke information from MODIS satellite images at 250 m resolution. Generalised estimating equations for Poisson data were used to assess the relationship between daily admissions and PM2.5, adjusted for weather, fungal spores (associated with asthma), weekend, zip code-level population and sociodemographics. Results: Associations of 2-day average PM2.5 with respiratory admissions were stronger during than before or after the fires. Average increases of 70 μg/m3 PM2.5 during heavy smoke conditions compared with PM2.5 in the pre-wildfire period were associated with 34% increases in asthma admissions. The strongest wildfire-related PM2.5 associations were for people ages 65–99 years (10.1% increase per 10 μg/m3 PM2.5, 95% CI 3.0% to 17.8%) and ages 0–4 years (8.3%, 95% CI 2.2% to 14.9%) followed by ages 20–64 years (4.1%, 95% CI −0.5% to 9.0%). There were no PM2.5–asthma associations in children ages 5–18 years, although their admission rates significantly increased after the fires. Per 10 μg/m3 wildfire-related PM2.5, acute bronchitis admissions across all ages increased by 9.6% (95% CI 1.8% to 17.9%), chronic obstructive pulmonary disease admissions for ages 20–64 years by 6.9% (95% CI 0.9% to 13.1%), and pneumonia admissions for ages 5–18 years by 6.4% (95% CI −1.0% to 14.2%). Acute bronchitis and pneumonia admissions also increased after the fires. There was limited evidence of a small impact of wildfire-related PM2.5 on cardiovascular admissions. Conclusions: Wildfire-related PM2.5 led to increased respiratory hospital admissions, especially asthma, suggesting that better preventive measures are required to reduce morbidity among vulnerable populations.
Doi 10.1136/oem.2008.041376
Pmid 19017694
Wosid WOS:000263557000009
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English