A placebo-controlled trial of a HEPA air cleaner in the treatment of cat allergy.
To evaluate the effect of a room high-efficiency particulate air (HEPA) cleaner on cat-induced asthma and rhinitis, 35 cat-allergic subjects who were living with one or more cats were studied in a double-blind, placebo controlled trial. After a 1 mo baseline period, subjects' bedrooms were equipped with an active or placebo air cleaner for the following 3 mo. Evaluations included monthly measurement of cat-allergen levels, daily morning, afternoon, and nighttime nasal- and chest-symptom scores, twice-daily measurement of peak-flow rates, daily medication scores, monthly spirometry, and methacholine (MCh) challenge testing before and after the study. Airborne allergen levels were reduced in the active-filter group as compared with the placebo group (p = 0.045). However, no differences were detected in settled-dust allergen levels (p = 0.485), morning, afternoon, or nighttime nasal-symptom scores (p = 0.769, 0.534, and 0.138), chest-symptom scores (p = 0.388, 0.179, and 0.215), sleep disturbance (p = 0.101), morning or afternoon peak-flow rates (p = 0. 424 and 0.679), or rescue medication use (nasal, p = 0.164, chest, p = 0.650), respectively. Although the combination of a HEPA room air cleaner, mattress and pillow covers, and cat exclusion from the bedroom did reduce airborne cat-allergen levels, no effect on disease activity was detected for any parameter studied.
Wood
R A
RA
Department of Pediatrics, Division of Allergy and Immunology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
Johnson
E F
EF
Van Natta
M L
ML
Chen
P H
PH
Eggleston
P A
PA
D000328:Adult; D000485:Allergens / Q000032:analysis*; D000818:Animals; D002415:Cats / Q000276:immunology*; D004311:Double-Blind Method; D004391:Dust / Q000032:analysis; D004780:Environment, Controlled; D005260:Female; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D006967:Hypersensitivity / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012129:Respiratory Function Tests; D016896:Treatment Outcome
D000485:Allergens; D004391:Dust