Prof Warner pointed to other research suggesting night time allergen exposure has the greatest impact on symptom severity, possibly because of changes in circulating hormone levels and immune responsiveness prompted by the body's internal clock, or circadian rhythm.None of those attempts were conclusively found to provide relief from symptoms.
The new treatment is a machine made by the Swedish company Airsonnett that simply provides a flow of cooled, filtered air around the sleeping person - the Protexo. This airflow seems to prevent allergens being breathed in by the sleeping person and thus prevents asthma triggers. Symptom reports by the patients are lower and clinical tests show key clinical markers for asthma have reduced.
Comparing this machine with identical dummy machines has conclusively shown that they work, and they work as well as the two drugs that are currently used to provide relief. This is the first time a treatment strategy that does not involve drugs has been shown to work as well as this.
This non-invasive technique could be useful for a wide range of patients including those who suffer from allergy to molds such as Aspergillus (often the most severe cases of asthma). The machines are not currently available for use in the home but their cost is already far less than the average spend on keeping asthmatic patients stable so they should be cost effective in the home once available.