title: The relationship of respiratory and cardiovascular hospital admissions to the southern California wildfires of 2003.
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 (PM(2.5)) during catastrophic wildfires in southern California in October 2003 was evaluated.
  
  
  METHODS
  Zip code level PM(2.5) concentrations were estimated using spatial interpolations from measured PM(2.5), 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 PM(2.5), adjusted for weather, fungal spores (associated with asthma), weekend, zip code-level population and sociodemographics.
  
  
  RESULTS
  Associations of 2-day average PM(2.5) with respiratory admissions were stronger during than before or after the fires. Average increases of 70 microg/m(3) PM(2.5) during heavy smoke conditions compared with PM(2.5) in the pre-wildfire period were associated with 34% increases in asthma admissions. The strongest wildfire-related PM(2.5) associations were for people ages 65-99 years (10.1% increase per 10 microg/m(3) PM(2.5), 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 PM(2.5)-asthma associations in children ages 5-18 years, although their admission rates significantly increased after the fires. Per 10 microg/m(3) wildfire-related PM(2.5), 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 PM(2.5) on cardiovascular admissions.
  
  
  CONCLUSIONS
  Wildfire-related PM(2.5) led to increased respiratory hospital admissions, especially asthma, suggesting that better preventive measures are required to reduce morbidity among vulnerable populations.
authors.affiliation: Epidemiology Department, School of Medicine, University of California-Irvine, 100 Theory Drive, Irvine, CA 92617-7555, USA. rdelfino@uci.edu
authors.forename: R J
authors.initials: RJ
authors.lastname: Delfino
authors.forename: S
authors.initials: S
authors.lastname: Brummel
authors.forename: J
authors.initials: J
authors.lastname: Wu
authors.forename: H
authors.initials: H
authors.lastname: Stern
authors.forename: B
authors.initials: B
authors.lastname: Ostro
authors.forename: M
authors.initials: M
authors.lastname: Lipsett
authors.forename: A
authors.initials: A
authors.lastname: Winer
authors.forename: D H
authors.initials: DH
authors.lastname: Street
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: T
authors.initials: T
authors.lastname: Tjoa
authors.forename: D L
authors.initials: DL
authors.lastname: Gillen
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000633:toxicity*; D001991:Bronchitis / Q000209:etiology / Q000628:therapy; D002140:California; D002318:Cardiovascular Diseases / Q000209:etiology* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D004190:Disasters; D004781:Environmental Exposure; D005390:Fires; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D052638:Particulate Matter; D011014:Pneumonia / Q000209:etiology / Q000628:therapy; D029424:Pulmonary Disease, Chronic Obstructive / Q000209:etiology* / Q000628:therapy; D012044:Regression Analysis; D012906:Smoke; D013172:Spores, Fungal; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D012906:Smoke