Traffic and outdoor air pollution levels near residences and poorly controlled asthma in adults.
BACKGROUND
Air pollution may exacerbate asthma.


OBJECTIVE
To investigate associations between traffic and outdoor air pollution levels near residences and poorly controlled asthma among adults diagnosed as having asthma in Los Angeles and San Diego counties, California.


METHODS
We estimated traffic density within 500 ft of 2001 California Health Interview Survey respondents' reported residential cross-street intersections. Additionally, we assigned annual average concentrations of ozone, nitrogen dioxide, particulate matter 2.5 and 10 micrometers or less in diameter, and carbon monoxide measured at government monitoring stations within a 5-mile radius of the reported residential cross-street intersections.


RESULTS
We observed a 2-fold increase in poorly controlled asthma (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.38-3.23) among asthmatic adults in the highest quintile of traffic density after adjusting for age, sex, race, and poverty. Similar increases were seen for nonelderly adults, men, and women, although associations seemed strongest in elderly adults (OR, 3.00; 95% CI, 1.13-7.91). Ozone exposures were associated with poorly controlled asthma among elderly adults (OR, 1.70; 95% CI, 0.91-3.18 per 1 pphm) and men (OR, 1.76; 95% CI, 1.05-2.94 per 1 pphm), whereas particulate matter 10 micrometers or less seemed to affect primarily women (OR, 2.06; 95% CI, 1.17-3.61), even at levels below the national air quality standard.


CONCLUSIONS
Heavy traffic and high air pollution levels near residences are associated with poorly controlled asthma.
Meng
Ying-Ying
YY
UCLA Center for Health Policy Research, Los Angeles, California 90024, USA. yymeng@ucla.edu
Wilhelm
Michelle
M
Rull
Rudolph P
RP
English
Paul
P
Ritz
Beate
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D001249:Asthma / Q000209:etiology*; D001336:Automobiles; D005260:Female; D006798:Housing; D006801:Humans; D008297:Male; D008875:Middle Aged; D052638:Particulate Matter / Q000009:adverse effects*
D052638:Particulate Matter