Reduction in mouse allergen exposure is associated with greater lung function growth

Abstract

Background: Current childhood asthma therapies have little effect on lung function trajectory. Objective: We sought to determine whether mouse allergen exposure reduction is associated with lung function growth in mouse-sensitized/exposed asthmatic children. Methods: Three hundred fifty mouse-sensitized/exposed asthmatic children (5-17 years old) were enrolled in a 1-year randomized trial of integrated pest management plus education versus education alone. Prebronchodilator/postbronchodilator spirometry was performed at baseline and 6 and 12 months, and bedroom floor mouse allergen levels were measured every 3 months. Mouse allergen reduction was defined as a 75% or greater decrease in mouse allergen levels from baseline. Treatment groups were combined for analyses because there were no differences in outcomes between groups. Changes in lung function over time were modeled, adjusting for age, sex, race, atopy, group, and bronchodilator reversibility and including an interaction term (allergen reduction*time). Results: The study population was predominantly black (79.4%) and low income (66.3% [<$30,000]). At baseline, the median mouse allergen level was 5.7 mg/g (interquartile range, 1.5-22.8 mg/g), and the mean (SD) prebronchodilator FEV 1 / forced vital capacity ratio was 80.2% (9.0%). Ninety-two (26.3%) participants had 75% or greater reduction in mouse allergen levels. For a 10-year-old black boy, 75% or greater allergen reduction was associated with an increase in prebronchodilator FEV 1 of 238 mL/y (95% CI, 177-299 mL/y), whereas less than 75% allergen reduction was associated with an increase in prebronchodilator FEV 1 of 131 mL/y (95% CI, 97-166 mL/y).

Asthma and the social determinants of health

“…[61][62][63] Pest allergen exposure has been repeatedly linked to risk of asthma, asthma prevalence, morbidity, and abnormal lung function. 59,[64][65][66][67] Recent data suggest that pest allergen exposure may lead to reduced lung function growth, 68 which has implications for future risk of adult lung disease and mortality. [69][70][71][72] Similarly, poor housing quality and housing disrepair are associated with risk of exposure to mold, 73 and exposure to mold is associated with childhood wheeze and asthma prevalence and morbidity.…”

The influence of urban exposures and residence on childhood asthma

“…93 A secondary analysis of this study found that significant reduction in mouse allergen exposure was associated with improved lung function growth over 1 year. 94 Yet, a different multifaceted allergen reduction study of children with asthma in New York City reported reduction in allergen exposure, but no change in asthma controller medication. 95 It is unclear as to why some studies have been successful in reducing allergen exposure and impacting asthma outcomes, while others either did not reduce allergen exposure or impact clinical outcomes.…”

Material Hardship and Indoor Allergen Exposure among Low-Income, Urban, Minority Children with Persistent Asthma

“…22 Grant et al observed that reducing mouse allergen exposure by ≥75% from baseline was associated with greater improvements in spirometry compared to those who did not achieve that reduction metric. 23 Finally, Matsui et al identified that a 50% decrease in bedroom floor mouse allergen was associated with significant reductions in asthma symptoms, short-acting β-agonist use, and healthcare utilization. 24 Here, we observed that cockroach and mouse allergen levels changed by 16.2% and 9.4%, respectively, with each unit of total material hardship.…”