Use of a HEPA Filter Associated with a Decrease in Urgent Medical Visits and Hospitalizations for Asthma among Children Living in Lower-Income New York City Apartments

The use of High Efficiency Particulate Air (HEPA) filters has been shown to reduce asthma exacerbations; however, the efficacy in lower-income urban apartments is less well studied. Secondary analyses of data from an environmental intervention trial was conducted to evaluate whether asthmatic children who were provided a HEPA filter in their homes had a greater improvement in asthma morbidity than those without a HEPA filter. Families living in lower-income communities in New York City with an asthmatic child age 7-17 years and report of mold in the home were recruited into a lower-cost home mold and excessive humidity reduction intervention study. HEPA filters were non-randomly distributed to some participants, specifically those reporting unfixed mold or leaks and/or cigarette smoke odor in the home. Families were requested to place the filter in the room where the asthmatic child spent most of the time. Comparing children with (n=11) versus without (n=29) HEPA filters in their homes, there was a frequency reduction in wheeze (36% vs 45%, respectively, P=0.73), but a greater decrease in urgent medical visits (73% vs 21%, P=0.007) and hospitalizations for asthma (36% vs. 6.9%P=0.039). These findings remained statistically significant (P<0.05) in models adjusting for age and sex and change in cockroach allergen, mouse allergen and report of mold. While these findings from a secondary analysis in a relatively small study must be interpreted with caution, they appear to support future studies designed to assess the impact HEPA filters in reducing asthma morbidity in lower-income urban communities.