Exposure to Alternaria alternata in US homes is associated with asthma symptoms.
BACKGROUND
Exposure to the fungus Alternaria alternata is a risk factor for asthma. Few studies have examined Alternaria exposures in indoor environments.


OBJECTIVE
We examined whether exposure to A alternata in US homes was associated with asthma-related outcomes.


METHODS
The data for this study were collected as part of the National Survey of Lead and Allergens in Housing. This cross-sectional study surveyed a nationally representative sample of 831 housing units inhabited by 2456 individuals in 75 different locations throughout the United States. An interviewer-administered questionnaire obtained information on demographics, household characteristics, and occupants' health status. Exposure to A alternata was assessed by measuring concentrations of A alternata antigens in vacuumed dust samples using a polyclonal anti-A alternata antibody assay. Dust samples were collected from a bed, a sofa, or a chair, and from bedroom, living room, and kitchen floors.


RESULTS
Lifetime prevalence of doctor-diagnosed asthma was 11.2%, and 6.9% of the study subjects reported active asthma symptoms in the past 12 months. The prevalence of current symptomatic asthma increased with increasing Alternaria concentrations in US homes; higher levels of A alternata antigens increased the odds of having asthma symptoms in the past year (relative to the lowest tertile, adjusted odds ratio was 1.52, 95% CI, 0.90-2.55 for the 2nd tertile; and 1.84, 95% CI, 1.18-2.85 for the 3rd tertile).


CONCLUSIONS
Exposure to A alternata in US homes is associated with active asthma symptoms.


CONCLUSIONS
Measures that reduce indoor exposure to A alternata may help control asthma exacerbations.
Salo
Päivi M
PM
National Institute of Environmental Health Sciences, National Institutes of Health (NIH), Research Triangle Park, NC 27709, USA.
Arbes
Samuel J
SJ
Sever
Michelle
M
Jaramillo
Renee
R
Cohn
Richard D
RD
London
Stephanie J
SJ
Zeldin
Darryl C
DC
D000293:Adolescent; D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D000528:Alternaria / Q000276:immunology*; D000946:Antigens, Fungal / Q000032:analysis / Q000276:immunology; D001249:Asthma / Q000453:epidemiology* / Q000382:microbiology*; D003430:Cross-Sectional Studies; D004391:Dust / Q000032:analysis / Q000276:immunology; D004781:Environmental Exposure; D005260:Female; D006798:Housing; D006801:Humans; D008297:Male; D015995:Prevalence
D000946:Antigens, Fungal; D004391:Dust