TITLE: A placebo-controlled trial of a HEPA air cleaner in the treatment of cat allergy.
AUTHORS: Wood RA; Johnson EF; Van Natta ML; Chen PH; Eggleston PA
AUTHOR AFFILIATION: Department of Pedatrics, Division of Allergy and Immunology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
SOURCE: Am J Respir Crit Care Med 1998 Jul; 158(1): 115-20
CITATION IDS: PMID: 9655716 UI: 98325291
ABSTRACT: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.