A double-blind study of the effectiveness of a high-efficiency particulate air (HEPA) filter in the treatment of patients with perennial allergic rhinitis and asthma.
This study was designed to assess the effectiveness of a high-efficiency particulate air (HEPA) filter in alleviating allergic respiratory symptoms. Thirty-two patients were studied who had symptomatic perennial rhinitis and/or asthma during the fall and winter months and had a positive skin test with house dust or house dust--mite extract. An ENVIRACAIRE room air cleaner was placed in the bedroom for 8 weeks. In a random manner, the active filter was used for 4 weeks and a blank filter for 4 weeks. There was an average 70% reduction in the particulate matter greater than or equal to 0.3 micron with the HEPA filter. In a double-blind design, results were assessed by analysis of the patients' symptom/medication scores and subjective evaluation. For the total study, there was no difference in the total symptom/medication scores or individual symptom scores during the placebo and active-filter periods. Analysis of the last 2 weeks of each filter period in which respiratory infection was absent demonstrated definite differences in total and individual symptoms, suggesting active-filter benefit. Patients' subjective responses also suggested benefit from the filter. The overall impression is that the HEPA filter can reduce allergic respiratory symptoms.
Department of Medicine, SUNY/Buffalo, N.Y.
R E
RE
Reisman
P M
PM
Mauriello
G B
GB
Davis
J W
JW
Georgitis
J M
JM
DeMasi
D000293:Adolescent; D000328:Adult; D000388:Air; D002648:Child; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D005260:Female; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012221:Rhinitis, Allergic, Perennial / Q000628:therapy*