Does an Air Purifier help asthma or allergies, is a common question asked among allergy specialists. There is evidence that indoor air pollution is associated with poor asthma outcomes, including hospitalizations and asthma medication use, poorer lung function and asthma-related mortality. So reducing indoor air pollution is likely important for improving outcomes in people with asthma.
High efficiency particulate air (HEPA) particle filtration devices are effective in reducing particulate matter concentrations, which is an important determinant in air quality. The evidence is unclear whether such technology actually improves respiratory outcomes. HEPA filters can capture particulate matter efficiently but older models may not capture gaseous pollutants.
A recent studied conducted investigated the effects of reducing the levels of pollutants in the bedroom and living room on asthma outcomes in adults using a HEPA air purifier (the Dyson Pure Cool Towers). The study outcome was whether the addition of this air purifier will improve asthma control and asthma quality of life because of a reduction in indoor pollutants level.
The results of the study showed that air pollutant levels were significantly lower in the intervention group, however there was no significant difference in the 2 groups in Asthma Control, Asthma specific Quality of Life or measures of lung function using spirometry.
Although the air purifier was able to lower the particulate matter indoors, it did not have a significant effect on asthma outcomes. The authors hypothesized that asthma is a complex heterogenous disease influenced by multiple factors in addition to just pollution and allergens driving it.
Airway remodeling and partial irreversibility over the long distance duration may have limited the scope for clinical improvement. Therefore a simple air purifier approach may not be so helpful in asthma
In conclusion, although improving air quality, an air purifier did not help or affect asthma control, however the study did not discuss allergy symptoms, which other studies have shown some benefit for allergic rhinitis symptoms.
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