Dust Mite Allergen Reduction Study

Abstract

RATIONALE: Asthmatics are encouraged to employ interventions to reduce exposure to indoor allergens, but often lack objective evidence to confirm the efficacy of their efforts. In-home test kits and education may influence dust mite allergen reduction. METHODS: This randomized controlled trial enrolled 60 households of children aged 5-15 years with parent-reported dust mite allergy and allergen concentrations ≥2μg/g in the child's bedroom. The intervention group (N = 30) received educational materials and in-home dust mite test kits at baseline, 1, 2, 5, and 8 months. The control group (N = 30) received only educational materials. Nonparametric sign tests were performed to determine the likelihood of mite levels decreasing vs. increasing. RESULTS: At baseline and 8 months, 37% and 61% of intervention households, respectively, had dust mite concentrations <2 μg/g and 7% and 4%, respectively, had >10μg/g in bed. At baseline and 8 months, 26% and 74% of intervention households, respectively, had dust mite concentrations <2 μg/g and 7% and 0%, respectively, had >10 μg/g on bedroom floor. Decreased dust mite levels from baseline to months 1, 2, 5 and 8 were statistically significant in floor (p < 0.002) and from baseline to months 2 and 5 in bed (p < 0.02). CONCLUSIONS: There was an increase in the number of tests with dust mite concentrations ≤2 ug/g and a decrease in the number of tests with dust mite concentrations >10 μg/g in the intervention group. Use of in-home test kits along with educational materials reduced dust mite allergen in bedrooms of children with reported dust mite allergy. The study had limited power to test other potential covariates.