Home environmental intervention in inner-city asthma: a randomized controlled clinical trial

doi:10.1016/S1081-1206(10)61012-5

Annals of Allergy, Asthma & Immunology

Volume 95, Issue 6, December 2005, Pages 518-524

https://doi.org/10.1016/S1081-1206(10)61012-5 Get rights and content

Background

Airborne pollutants and indoor allergens increase asthma morbidity in inner-city children; therefore, reducing exposure, if feasible, should improve asthma morbidity.

Objective

To conduct a randomized controlled trial of methods to reduce environmental pollutant and allergen exposure in the homes of asthmatic children living in the inner city.

Methods

After the completion of questionnaires, spirometry and allergen skin tests, home inspection, and measurement of home air pollutant and allergen levels, 100 asthmatic children aged 6 to 12 years were randomized to the treatment group (home-based education, cockroach and rodent extermination, mattress and pillow encasings, and high-efficiency particulate air cleaner) or to the control group (treated at the end of the 1-year trial). Outcomes were evaluated by home evaluations at 6 and 12 months, clinic evaluation at 12 months, and multiple telephone interviews.

Results

In the treatment group, 84% received cockroach extermination and 75% used the air cleaner. Levels of particulate matter 10 μm or smaller declined by up to 39% in the treatment group but increased in the control group (P < .001). Cockroach allergen levels decreased by 51% in the treatment group. Daytime symptoms increased in the control group and decreased in the treatment group (P = .04). Other measures of morbidity, such as spirometry findings, nighttime symptoms, and emergency department use, were not significantly changed.

Conclusions

A tailored, multifaceted environmental treatment reduced airborne particulate matter and indoor allergen levels in inner-city homes, which, in turn, had a modest effect on morbidity.

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: This study was supported by grant R82672401 from the US Environmental Protection Agency, grant ES09606 from the National Institute of Environmental Health Sciences, grant HL058942 from the National Heart, Lung, and Blood Institute, and a grant from the US Environmental Protection Agency's Science to Achieve Results (STAR) program.

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ORIGINAL ARTICLESHome environmental intervention in inner-city asthma: a randomized controlled clinical trial

Background

Objective

Methods

Results

Conclusions

J Pediatr.

J Allergy Clin Immunol.

Environ Res.

Environ Res.

J Allergy Clin Immunol.

Ann Allergy Asthma Immunol.

J Allergy Clin Immunol.

J Allergy Clin Immunol.

J Allergy Clin Immunol.

J Allergy Clin Immunol.

The role of cockroach allergy and exposure to cockroach allergen in causing morbidity among inner-city children with asthma

N Engl J Med.

Parental smoking and childhood asthma: longitudinal and case-control studies

Thorax.

The effect of air pollution on inner city children with asthma

Eur Respir J.

Results of a home-based environmental intervention among urban children with asthma

N Engl J Med.

Enhanced nasal cytokine production in human beings after in vivo challenge with diesel exhaust particles

J Allergy Clin Immunol.

Residual oil fly ash amplifies allergic cytokines, airway responsiveness and inflammation in mice

Am J Respir Crit Care Med.

Design and methods of the methods of the National Cooperative Inner-City Asthma Study

Pediatr Pulmonol.

ORIGINAL ARTICLES
Home environmental intervention in inner-city asthma: a randomized controlled clinical trial