Effects of Reducing Indoor Air Pollution on the Adult Asthmatic Response

The investigators seek to determine the effect of placing air cleaner devices in the homes of
adults with asthma on their asthma health. To this end, the investigators aim to study 40
adults with asthma that are 18-50 years of age and live in Baltimore. They will receive
either true air cleaners or sham cleaners in a blinded, randomized manner for one month, and
then, after a washout period, they will cross over and receive the other intervention (sham
or true cleaner). All participants will have environmental monitoring (personal and in-home)
to determine their particulate matter exposure, and be followed repeatedly during the 3 month
study period for markers of asthma disease, including respiratory symptoms, medication and
health care utilization, pulmonary function, airway hyperresponsiveness, systemic markers of
inflammation, and bronchoscopic evidence of airway inflammation or epithelial cell
dysfunction. Modifying factors or factors influencing susceptibility, such as diet and
nutritional status, will also be explored.

Inclusion Criteria:

- Age 18-50 years of age

- Non-smoker (<100 cigarettes in lifetime)

- Physician diagnosis of asthma

- Symptoms of asthma and/or reliever medication use in the past 6 months

- Living in the current residence >= 6 months within Baltimore

- Enrollment in, and completion of, the observational environmental asthma study "Inhale
1"

Exclusion Criteria:

- Current diagnosis of another major pulmonary disease, other significant morbidity

- Pregnancy (as defined by a positive urine pregnancy test at screening of all women of
child-bearing potential)

- Planning to relocate residence or activity that necessitates travel away from home for
prolonged period of time during the study period

- Current use of an air cleaner in the home