Pediatric pulmonologist Christy Sadreameli discusses her secondary analysis of the Mouse Allergen and Asthma Intervention Trial (MAAIT). The original MAAIT study is a randomized, controlled trial of a home intervention to reduce mouse allergen exposure in mouse-allergic children who have asthma and mouse allergen exposure. In Sadreameli’s secondary study, the researchers determined if three factors in the home were associated with improvement in asthma outcomes: lower baseline home mouse allergen level, lower level of particulate matter, and sensitization and exposure to other indoor allergens.
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pubmed.ncbi.nlm.nih.gov/34506964. Hi, my name is dr Christie Sandra Mellie and I'm an assistant professor of pediatrics and pediatric pulmonologist at johns Hopkins. The home environment can be an important factor in asthma symptoms. That is where as it is, where Children spend a lot of their time. Previous studies have shown that mouse sensitization and home exposure is associated with increased asthma symptoms and exacerbations, particularly for Children living in urban environments who are majority low income and from ethnic and racial minority groups. Mouse allergen is a really common exposure in homes in Baltimore city and other cities in the mid atlantic and northeast. Therefore it can be a major factor in asthma morbidity in these environments. A study called the mouse allergen and asthma intervention trial, or mate for short, was a randomized clinical trial done in Children ages 5 to 17 with asthma living in Baltimore or boston and sensitized and exposed to mouse in their home mate tested whether an intensive pest management intervention was effective to improve asthma outcomes compared with a control group who received education alone mate was designed and carried out by a group of talented researchers, including one of my mentors dr Elizabeth Matsui. Something interesting about mate is that there were widespread reductions in mouse allergen amounts across the study regardless of the study group assignment and mouse allergen reduction was associated with improvement and a variety of asthma outcomes, including symptom and exacerbation outcomes with my mentor. Dr Matsui. I performed a secondary analysis of mate to determine if other factors in the home were associated with greater or lesser improvements and asthma outcomes in response to mouse allergen reduction. For our secondary analysis, we combine the two groups control and intervention since mouse allergen levels and asthma outcomes did not differ between the two groups. We studied three factors in order to determine whether they modified the clinical response to reduction in mouse allergen. These factors were baseline or starting level of mouse allergen at study entry level of particulate matter, 10 microns or smaller PM 10, a measure of indoor air quality and sensitization and exposure to other common indoor allergens such as cat, dog dust mite, cockroach. Things like that Exposures and homes were measured at study entry six months and 12 months and outcomes were measured by phone calls, interviewing study participants and these included exacerbations and day and night time symptoms. We found that higher baseline levels of mouse allergen in the home were associated with greater improvements in many asthma outcomes in response to mouse allergen reduction. So starting at a higher level of allergen had higher benefit than starting at a lower level of mouse allergen. Lower levels of PM 10 were associated with greater response to mouse allergen reduction as well. And finally, sensitization and exposure to other indoor allergens did not appear to have a significant impact on the clinical benefits seen with mouse allergen reduction. We concluded that mouse allergen reduction was still very helpful even if mouse allergen levels were very high to start with. In fact possibly even more beneficial for these Children. And we also concluded that PM 10 would be an area to consider targeting in future multipronged intervention studies. Finally, sensitization and exposure to other inter allergens, not having an effect on the clinical response to mouse allergen reduction was kind of interesting because it means even if Children have other allergies and exposures focusing on mouse may still be quite helpful for them. Thanks for listening. And I'd like to thank my mentor, Dr Matsui, the mate, co investigators, the study participants and of course, my co workers and the division of pediatric pollen ology.