Clinical evaluation of the effect of anti-allergic mattress covers in patients with moderate to severe asthma and house dust mite allergy: a randomised double blind placebo controlled study

Abstract

Background: The use of anti-allergic mattress covers in patients with asthma can result in a large reduction in the level of house dust mite allergen in dust samples. Apart from a reduction in histamine induced bronchial hyperresponsiveness, there are few data on the effect of mattress covers on clinical efficacy and quality of life in patients with moderate to severe asthma. Methods: Thirty patients with asthma and house dust mite allergy were studied in a randomised, double blind, placebo controlled study. Before and after using anti-allergic covers for 1 year, dust was collected from the mattresses to determine concentrations of Dermatophagoides pteronyssinus (Der p 1), and bronchial hyperresponsiveness and quality of life were measured. The patients scored their symptoms (lungs and nose), morning and evening peak flow values, and rescue medication for 14 days before and after the intervention period.Results: There was a significant reduction in the concentration of Der p 1 in the dust collected from the mattresses in the actively treated group after 1 year compared with before treatment; no change was found in the placebo group. In both the actively treated and placebo groups there was no significant improvement in PC 20 histamine. Quality of life improved similarly in both groups. The symptom score of the lower airways did not significantly change in either group. A significant decrease in nasal symptom score was seen in the actively treated group compared with before treatment, but there was no significant difference between the groups. No changes in morning and evening peak flow values, peak flow variability, nor in the use of rescue medication were found in either group. Conclusion: The use of anti-allergic mattress covers results in significant reductions in Der p 1 concentrations in carpet-free bedrooms. However, in patients with moderate to severe asthma, airways hyperresponsiveness and clinical parameters are not affected by this effective allergen avoidance.

Encasement of Bedding Does Not Improve Asthma in Atopic Adult Asthmatics

“…A recent randomized placebo-controlled trial conducted in an area with low ambient HDM allergen levels demonstrated a significant reduction in allergen levels in the intervention group over a 6-month period, but not over a 12-month period [12]. However, similar studies conducted in areas with high indoor HDM allergen levels, such as in Australia, have shown that the encasement of bedding with impermeable covers leads to a significant reduction in HDM allergen levels [10, 22 ]even after 12 months. The reduction of allergen levels in one of these studies [22 ]has been associated with a reduction in the required dose of inhaled corticosteroid in asthmatic children, suggesting that such an intervention can have a positive impact.…”

“…Clinical benefits of this intervention are likely to be confined to the subgroup of atopic asthmatics whose asthma is precipitated by HDM allergen exposure. Three randomized controlled trials [10,11,12] that included encasement of bedding investigated patients with mild to moderate asthma and sensitization and showed substantial reductions in Der p 1 levels, but these reductions had no clinical impact. …”

Exposure to Indoor Allergens in Homes of Patients with Asthma and/or Rhinitis in Southeast Brazil: Effect of Mattress and Pillow Covers on Mite Allergen Levels

“…However, controlled studies in homes of children and adults have provided conflicting results [8]. Recent studies have failed to show major benefits of successful reduction of mite allergens in causing a decrease in asthma or atopic dermatitis symptoms in patients with well-established disease, or in preventing the development of respiratory symptoms, atopic dermatitis or atopic sensitization in early childhood [9, 10]. On the other hand, other well-controlled studies have provided evidence of a beneficial effect [11, 12, 13, 14, 15, 16].…”

Assessment of health-related quality of life in paediatric asthma patients

“…The study of Rijssenbeck-Nouwens L H et al also shown that early childhood asthma is more common among males, but after puberty the incidence in females and decreases in males. 8 In addition, asthma after childhood is more severe in females than in males. In my study also correlated to that of previous study.…”