Endotoxin clustering with allergens in house dust and asthma outcomes in a U.S. national study

Abstract

Background: Endotoxin is ubiquitous in the environment, but its clustering with indoor allergens is not well characterized. This study examined the clustering patterns of endotoxin with allergens in house dust and their association with asthma outcomes. Methods: We analyzed data from 6963 participants of the 2005-2006 National Health and Nutrition Examination Survey. House dust sampled from bedroom floor and bedding was evaluated for endotoxin and allergens from fungi, cockroach, dog, cat, mites, and rodents. Two-step cluster analysis and logistic regressions were performed to identify the clustering patterns and their associations with current asthma and wheeze in the past 12 months, adjusting for covariates. Results: Of the homes, 17.8% had low endotoxin and allergen levels in house dust (Cluster 1). High endotoxin level clustered with Alternaria and pet allergens in the homes of participants with a high socioeconomic status who own pets (Cluster 2) (48.9%). High endotoxin clustered with Aspergillus, dust mites, cockroach, and rodent allergens in the homes of participants with low socioeconomic status (Cluster 3) (33.3%). Compared to Cluster 1, Cluster 2 was associated with higher asthma prevalence (OR 1.42, 95% CI: 1.06-1.91) and wheeze (OR 1.32, 95% CI: 1.07-1.63). Cluster 3 was positively associated with wheeze only in participants sensitized to inhalant allergens (OR 1.42, 95% CI: 1.06-1.91) or exposed to tobacco smoke (OR 1.72, 95% CI: 1.15-2.60). Conclusions:The clustering of endotoxin with allergens in dust from homes with pets or of people with low socioeconomic status is associated with asthma and wheeze.

Effects of early‐life exposure to dust mite allergen and endotoxin on the development of asthma and wheezing: The Japan Environment and Children's Study

“…11 Furthermore, recent studies in adult Americans revealed that the influence on allergic disease differs due to climate and lifestyle because of differences in exposure to endotoxin and indoor allergens such as mites and moulds. 12,13 Therefore, it is necessary to clarify the association of exposure to dust mite allergen and endotoxin with asthma development in Asian regions under different climatic regions and lifestyles in comparison with that in Western countries. Although large-scale birth cohort studies have been conducted in Western countries, there are few reports from Asia, including Japan.…”

Precision Medicine for Paediatric Severe Asthma: Current Status and Future Direction

“…These children often become controlled when these factors are addressed. Modifiable factors include poor medication adherence, 22 exposure to environmental factors such as pet allergens 23 and other indoor allergens such as fungi, 13 exposure to tobacco smoke, 24 air pollution, 25 and psychosocial factors. 26…”

Exposures in the Indoor Environment and Prevalence of Allergic Conditions in the United States of America

“…NHANES did not test for Alternaria or Cladosporium allergens, or black molds (e.g., Stachybotrys chartarum ), which are increasingly acknowledged allergenic sources and may be associated with worse asthma control in some cases (Segura-Medina et al, 2019) [ 42 ], this being another limitation of our study. A cluster analysis that Mendy et al (2020) [ 43 ] used would have assessed real life exposures. Indeed, the authors found out that the clustering of endotoxin with allergens in dust from homes with a pet or of people with low SES is associated with asthma and wheeze.…”