Research suggests filter device can ease asthma symptoms

A device that filters out airborne asthma triggers during sleep can ease persistent symptoms of the condition during the day and improve quality of life, according to new research.

Temperature-controlled laminar airflow treatment (TLA), is said to deliver a constant, slightly cooled airflow in the patient’s breathing area, which displaces warmer air containing irritants and allergens, including house dust mites and pet hairs.

According to a statement from the BMJ, the aim is to stave off the abnormal immune response that triggers a systemic allergic reaction, including the airway narrowing typical of an asthma attack, by preventing the sleeper breathing in the irritants and allergens.

Researchers from European asthma clinics, who have published their findings online in the BMJ journal Thorax, base their findings on 281 non-smokers aged between seven and 70, from six European countries. All of them had poorly controlled atopic (allergic) asthma.

Of these, 189 slept with a TLA device (Protexo) just above their bed for a year with the remainder using a dummy device.

A validated score was used to assess quality of life before and after the 12-month study period, in conjunction with assessments of symptom control, lung capacity, airway inflammation, and biological indicators of a systemic allergic response.

The results are said to have showed a significant difference of 14–15 per cent on quality of life scores between those using Protexo and those using the dummy device.

A steeper fall in nitric oxide — an indicator of inflammation — was seen among those using Protexo, and this was particularly noticeable among those with more severe asthma. Those using this device also had significantly smaller increases in another indicator of persistent and more severe inflammation — immunoglobulin E (IgE).

The impact was greatest among those whose asthma required the most medication yet whose symptoms were the most poorly controlled, a group who ‘represent a significant area of unmet need’, said the authors.