Mar 1, 2009

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

by
R J Delfino, S Brummel, J Wu, H Stern, B Ostro, M Lipsett, A Winer, D H Street, L Zhang, T Tjoa, D L Gillen
,
Occupational and Environmental Medicine
  • Evaluates 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
  • Finds that associations of 2-day average PM2.5 with respiratory admissions were stronger during than before or after the fires
  • Finds 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
  • Finds that 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%)
  • Finds there were no PM2.5–asthma associations in children ages 5–18 years, although their admission rates significantly increased after the fires
  • Finds that, 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%)
  • Finds acute bronchitis and pneumonia admissions also increased after the fires
  • Finds there was limited evidence of a small impact of wildfire-related PM2.5 on cardiovascular admissions