Asthma narrows the airways and can make it difficult for children to breathe, which sometimes can lead to a trip to the emergency room. Current asthma treatment involves medication and lifestyle changes, such as avoiding asthma triggers. One common trigger is the house dust mite, which is a microscopic creature that feeds on human skin flakes and produces feces that triggers asthma symptoms.

Researchers wanted to evaluate the use of dust mite-impermeable bedding and its impact on severe asthma exacerbations in children. The study, published in the American Journal of Respiratory and Critical Care Medicine, found that dust mite-impermeable bedding may be effective in reducing the number of hospitalizations and/or emergency room visits of mite-sensitized children with asthma.

About the study

The randomized controlled trial included 284 participants with dust mite sensitization and asthma with an average age of 7.7 years old. Participants were randomly assigned to receive mite-impermeable bedding or similar appearing bedding that was not mite-impermeable for their pillow, mattress, and duvet. Participants had similar characteristics, including allergen exposure. Carpets can collect a lot of dust, but the percent of children with carpets in each group was not given.

Telephone interviews with the primary caregiver were conducted at 1, 4, and 12 months regarding exacerbations, unscheduled medical care, and medication use. Mite allergen was measured in vacuumed dust samples collected from the child's mattress and floor both before and after the study. Quality of life was assessed using a parent questionnaire.

At 12 months, 41.5% in the control group received unscheduled medical care compared to 29.3% of children in the active group. Mite allergens in mattress samples were reduced by 84% in the active group with no change in the control group. There was no change in any of the floor samples

The study did not find a difference in the number of children who received a course of oral corticosteroids for asthma exacerbation between the active and control groups. Furthermore, parents of both groups reported significantly improved quality of life during the time of the study with no significant difference between the 2 groups.

How Does this Affect You?

A randomized trial is considered the most reliable form of research, but how the research is done will affect its reliability. Although the study revealed that dust-mite bedding may reduce emergency room visits and/or hospitalization, 9 children would have to use the bed covers to prevent 1 child from having any visits. Both groups reported significantly improved quality of life during the time of the study. It is unknown whether parents used other methods of cleaning that may have improved quality of life during the study period. This trial should be compared to previous studies which determined that dust mite barrier bedding is clinically ineffective.

Talk to your child's doctor about whether mite-impermeable bedding would be useful to your child. Other lifestyle factors to prevent flare ups include keeping moisture low in the house, vacuuming regularly with a vacuum that has a HEPA filter, and using pesticides against mites as needed.