STUDY:

JOURNAL: Chest 2002;122:1535-1542.

AUTHORS: Ellen McDonald

ABSTRACT: Overall, the use of air filters is associated with fewer symptoms among patients with allergies and asthma.

---

COMMENTARY: Ellen McDonald, RN and colleagues from McMaster University, Hamilton, Ontario, Canada, systematically reviewed the evidence of 10 randomized trials evaluating the effects of air filtration systems on asthmatic patients.

They abstracted data on the methodolgic quality, population, intervention, and outcomes from studies identified using MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Collaboration.

Of the 10 studies reviewed, five enrolled adults only and one included children only. A total of 216 patients were included in all the studies, with the sample size ranging from 9 to 45 subjects.

A significant decrease in airway responsiveness associated with air filter use was reported in two studies. An association was observed between air filters and significantly lower total symptoms scores and lower sleep disturbance score.

The investigators observed no association between air filter utilization and any differences in medication use or morning peak expiratory flow values.