title: Encasement of bedding does not improve asthma in atopic adult asthmatics.
abstract: OBJECTIVE
  We evaluated the impact of impermeable bed covers on asthma in asthmatics with clinically relevant house dust mite (HDM) sensitization.
  
  
  METHODS
  The study included 32 HDM-sensitized asthmatics in whom HDM allergy was considered as a significant factor in their asthma. They were randomized into either an intervention group whose bedding was encased with impermeable covers, or a control group who received cotton covers. Before and 3 and 6 months after encasement, dust samples were collected from the bedding and assayed for Der p 1. Clinical outcomes included quality of life, lung function, bronchial reactivity to methacholine, symptoms, medications and peak flow rates.
  
  
  RESULTS
  Baseline Der p 1 levels in both the active and the placebo groups were comparable and high (19.2 vs 18.9 microg/g of dust). There was a significant reduction in Der p 1 levels in the active group after 6 months, but not in the placebo group (7.3 vs 21.9 microg/g of dust). Quality of life improved significantly in both the intervention and control groups, but there was no significant difference in the improvements between the groups. There was no significant change in lung function, symptoms, and requirements for medications.
  
  
  CONCLUSIONS
  Encasement of bedding significantly reduced the Der p 1 levels. However, this was not sufficient to produce worthwhile clinical improvement in those in whom dust mite avoidance might well have been recommended as part of their clinical management.
authors.affiliation: Department of Public Health, The University of Melbourne, Australia. s.dharmage@unimelb.edu.au
authors.forename: S
authors.initials: S
authors.lastname: Dharmage
authors.forename: E H
authors.initials: EH
authors.lastname: Walters
authors.forename: F
authors.initials: F
authors.lastname: Thien
authors.forename: M
authors.initials: M
authors.lastname: Bailey
authors.forename: J
authors.initials: J
authors.lastname: Raven
authors.forename: C
authors.initials: C
authors.lastname: Wharton
authors.forename: J
authors.initials: J
authors.lastname: Rolland
authors.forename: L
authors.initials: L
authors.lastname: Light
authors.forename: N
authors.initials: N
authors.lastname: Freezer
authors.forename: M
authors.initials: M
authors.lastname: Abramson
mesh_terms: D000328:Adult; D039741:Antigens, Dermatophagoides / Q000032:analysis*; D060829:Arthropod Proteins; D001249:Asthma / Q000276:immunology / Q000517:prevention & control*; D001513:Beds; D003546:Cysteine Endopeptidases; D040002:Dermatophagoides pteronyssinus / Q000276:immunology*; D004391:Dust / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008297:Male; D011788:Quality of Life
chemical_list: D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D004391:Dust; D003546:Cysteine Endopeptidases; C451162:Dermatophagoides pteronyssinus antigen p 1