The Airports, Air Quality, and Asthma (AAA) Study

Conditions studied

Pediatric Asthma

About this study

For children with asthma, exposure to indoor air pollution increases the risk of a serious asthma exacerbation, which can be life-threatening. Interventions aimed at improving indoor air quality, including use of a portable air cleaner with a high-efficiency particulate air (HEPA) filter, can reduce this risk, but the effectiveness, feasibility and acceptability of HEPA air cleaners varies by setting. In collaboration with a community health worker (CHW) delivered asthma education program, the investigators are conducting a randomized clinical trial to evaluate the effectiveness of HEPA air cleaners to improve indoor air quality and child asthma health in South King County of Washington state, a vulnerable community impacted by air pollution from airports and highway traffic. Key features of the Airports, Air Quality and Asthma (AAA) design include integration of CHWs into study procedures, including CHWs recruited from community-based organizations, into multiple aspects of the trial protocol. The investigators aim to recruit up to N=60 children with asthma randomized into intervention and control groups in a 1:1 ratio, conduct baseline assessments of indoor air quality and airway health, and collect repeated assessments of air quality and airway health during the three-month intervention period and after the trial concludes. Study findings will inform future approaches to integrate HEPA air cleaners into existing CHW asthma education programs in this and similar communities.

Interventions

• Device: Portable air cleaner with HEPA filter — The Winix 9800 is a true HEPA air cleaner that has been AHAM (Association of Home Appliance Manufacturers) Verifide® for rooms that are 500 square feet in size. The air cleaner has a washable fine mesh pre-filter that captures large airborne particles, an activated carbon filter that reduces volatile organic compounds and odors, and a true HEPA filter that captures 99.99% of airborne allergens as small as 0.003 microns in size.
• Device: Less effective portable air cleaner (no HEPA) — Winix 9800 air cleaner, with data logging energy use monitor is installed in the child's bedroom. In the sham group, the Winix 9800 true HEPA filter and activated carbon filter were removed. This was an internal modification and not visible to the user. The air cleaner still included a washable fine mesh pre-filter that captures large airborne particles.

Primary outcomes

• Symptom days over 7 days (Repeated measure, assessed on a weekly basis throughout the 3 month observation period.)
• Change in Asthma Control Score (From the baseline visit until the end of study follow-up, 3 months later.)

Eligibility information

Study locations

• University of Washington, Seattle, Washington 98195 United States