Impermeable dust mite covers in the primary and tertiary prevention of allergic disease: a meta-analysis.
BACKGROUND
Up to 40% of the world's population has been diagnosed with an allergic disease. The most prevalent allergy is to house dust mites. Impermeable mattress covers are often the first treatment in the prevention and decrease of symptoms of allergic disease.


OBJECTIVE
To perform a meta-analysis evaluating the effectiveness of impermeable mattress covers in the primary prevention of allergic disease and as a single intervention in the tertiary prevention of allergic disease symptoms.


METHODS
MEDLINE, Embase, Web of Science, and CINAHL were systematically searched for relevant publications. Seven primary prevention trials (n = 3,461) and 17 tertiary prevention trials (n = 1,671) met the inclusion criteria and were included in the review. All article reviews and abstractions were performed in duplicate.


RESULTS
No significant pooled relative risks were found for the prevention of allergic disease. The pooled relative risks were 0.97 (95% confidence interval [CI] 0.62-1.51) for house dust mite sensitization, 0.92 (95% CI 0.81-1.05) for wheeze, 0.85 (95% CI 0.70-1.02) for asthma, 1.03 (95% CI 0.90-1.19) for allergic rhinitis, and 1.05 (95% CI 0.84-1.32) for allergic dermatitis. Likewise, no significant pooled standardized mean differences were found in the tertiary prevention of symptoms. The pooled standardized mean differences were -0.03 (95% CI -0.15 to 0.09) for peak flow, -0.06 (95% CI -0.32 to 0.20) for asthma symptom score, and -0.39 (95% CI -0.88 to 0.11) for nasal symptom score. A significant effect was seen in the decrease of house mite dust level in the mattress (-0.79, 95% CI -0.98 to -0.60).


CONCLUSIONS
No evidence was found to support the use of impermeable mattress covers in the primary prevention of allergic disease or in the tertiary prevention of allergic disease symptoms.
Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana. Electronic address: warroyav@tulane.edu.
Whitney D
WD
Arroyave
Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana.
Felicia A
FA
Rabito
Department of Pediatrics, Tulane School of Medicine, New Orleans, Louisiana.
John C
JC
Carlson
Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana.
Eleanor E
EE
Friedman
Department of Epidemiology, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana.
Sarah J
SJ
Stinebaugh
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001249:Asthma / Q000276:immunology / Q000517:prevention & control; D001512:Bedding and Linens; D001513:Beds; D002648:Child; D002675:Child, Preschool; D003876:Dermatitis, Atopic / Q000276:immunology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D011322:Primary Prevention / Q000379:methods*; D039981:Pyroglyphidae / Q000276:immunology*; D055502:Secondary Prevention / Q000379:methods*; D055815:Young Adult