학술논문

Spatial modeling connecting childhood atopic dermatitis prevalence with household exposure to pollutants
Document Type
Original Paper
Source
Communications Medicine. 4(1)
Subject
Language
English
ISSN
2730-664X
Abstract
Background: Atopic dermatitis (AD) is a chronic, inflammatory disease characterized by dry, pruritic skin. In the U.S., the prevalence of AD has increased over three-fold since the 1970s. We previously reported a geographic association between isocyanate-containing air pollution and AD as well as mechanistic data demonstrating that isocyanates induce skin dysbiosis and activate the host itch receptor TRPA1. However, non-spatial models are susceptible to spatial confounding and may overlook other meaningful associations.Methods: We added spatial analysis to our prior model, contrasting pollution data with clinical visits. In addition, we conducted a retrospective case-control survey of childhood exposure to BTEX-related products. Finally, we assessed implicated compounds, in pure form and as part of synthetic fabric, for their effect on the growth and metabolism of skin commensal bacteria.Results: Spatial analysis implicate benzene, toluene, ethylbenzene, and, most significantly, xylene (BTEX) compounds. Survey odds ratios for AD were significant for xylene-derived polyester bed sheets (OR = 9.5; CI 2.2–40.1) and diisocyanate-containing wallpaper adhesive (OR = 6.5; CI 1.5–27.8). Staphylococcus aureus lives longer on synthetic textiles compared to natural textiles. Meanwhile, synthetic fabric exposure shifts the lipid metabolism of health-associated commensals (Roseomonas mucosa and S. epidermidis) away from therapeutic pathways.Conclusions: We propose that BTEX chemicals in their raw forms and in synthetic products represent a unifying hypothesis for environmentally induced AD flares through their ability to create dysbiosis in the skin microbiota and directly activate TRPA1. Unequal distribution of these pollutants may also influence racial disparities in AD rates.
Plain language summary: Atopic dermatitis (AD) is a chronic, inflammatory disease characterized by dry, itchy skin that has become increasingly more common since around 1970. We aimed to identify chemicals that may cause atopic dermatitis (eczema). Building on prior work, we discovered that these chemicals could prevent the good bacteria that live on the skin from making the lipids and oils needed to keep human skin healthy. In this study, we combined new research methods with patient surveys. We link eczema to the chemical xylene, which is found in numerous home products. Exposure to xylene, benzene, or isocyanate containing fabrics (polyester, nylon, or spandex) disrupted the normal functions of skin bacteria. Our results indicate exposure to synthetic fabrics and other sources of these chemicals may contribute to eczema and deepen the understanding of how the environment can drive common diseases.
Ratley, Zeldin et al. implicate xylene in the pathogenesis of atopic dermatitis by combining spatial analysis and patient surveys with prior epidemiological and mechanistic data. They propose that exposure of healthy skin commensals to xylene, benzene and isocyantes in synthetic fabrics disrupts normal lipid metabolism and activates itching.