Effect of catastrophic wildfires on asthmatic outcomes in obese children: breathing fire.
BACKGROUND
Air pollutants from wildfires and obesity independently exacerbate asthma, yet no study has determined the combined effects of these 2 variables on asthma outcomes.


OBJECTIVE
To determine the effect of 2 catastrophic wildfires affecting the Southern California region (in 2003 and 2007) on several asthma outcomes in a cohort of children.


METHODS
To investigate the association between wildfire exposure and asthma outcomes, we stratified our study population by body mass index categories (underweight, normal, overweight, and obese) and zip codes (to distinguish individuals who were closer to the fires vs farther away). The primary outcome was the prevalence of physician-dispensed short-acting β-agonist (SABAs). Secondary outcomes included the rate of emergency department visits and/or hospitalizations for asthma, the frequency of oral corticosteroid use for asthma, and number of new diagnoses of asthma.


RESULTS
A total of 2,195 and 3,965 asthmatic children were analyzed as part of our retrospective cohort during the 2003 and 2007 wildfires, respectively. SABA dispensing increased the most in the obese group after the 2003 wildfires (P < .05). Increased prevalence of SABA dispensing was also noted in the obese group in 2007, but this was not statistically higher than the increases seen in other body mass index groups. There was no observed increase in emergency department and/or hospitalization rates, oral corticosteroid dispensing frequency, or new asthma diagnoses after either wildfire.


CONCLUSIONS
Catastrophic wildfires lead to worsening asthma outcomes, particularly in obese individuals. This study gives further evidence of a link between obesity and asthma severity and suggests that air pollutants released during wildfires can have substantial detrimental effects on asthma control.
Department of Allergy, Kaiser Permanente Medical Center, San Diego, California; Department of Medicine, Division of Rheumatology, Allergy, and Immunology, University of California at San Diego, La Jolla, California. Electronic address: kevin.y.tse@kp.org.
Kevin
K
Tse
Department of Research and Evaluation, Kaiser Permanente Medical Center, Pasadena, California.
Lie
L
Chen
Department of Allergy, Kaiser Permanente Medical Center, San Diego, California; Department of Medicine, Division of Rheumatology, Allergy, and Immunology, University of California at San Diego, La Jolla, California.
Mabel
M
Tse
Department of Medicine, Division of Rheumatology, Allergy, and Immunology, University of California at San Diego, La Jolla, California.
Bruce
B
Zuraw
Department of Allergy, Kaiser Permanente Medical Center, San Diego, California; Department of Medicine, Division of Rheumatology, Allergy, and Immunology, University of California at San Diego, La Jolla, California.
Sandra
S
Christiansen
D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D001249:Asthma / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D002140:California / Q000453:epidemiology; D002388:Catastrophic Illness; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects; D005390:Fires; D006801:Humans; D008297:Male; D009765:Obesity / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D017063:Outcome Assessment, Health Care; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012119:Respiration; D012189:Retrospective Studies; D015208:Smoke Inhalation Injury / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*
D000318:Adrenergic beta-Agonists