BACKGROUND Changes in land use and climate change have been reported to reduce biodiversity of both the environment and human microbiota. These reductions in biodiversity may lead to inadequate and unbalanced stimulation of immunoregulatory circuits and, ultimately, to clinical diseases, such as asthma and allergies. OBJECTIVE We summarized available empirical evidence on the role of inner (gut, skin, and airways) and outer (air, soil, natural waters, plants, and animals) layers of biodiversity in the development of asthma, wheezing, and allergic sensitization. METHODS We conducted a systematic search in SciVerse Scopus, PubMed MEDLINE, and Web of Science up to 5 March 2024 to identify relevant human studies assessing the relationships between inner and outer layers of biodiversity and the risk of asthma, wheezing, or allergic sensitization. The protocol was registered in PROSPERO (CRD42022381725). RESULTS A total of 2,419 studies were screened and, after exclusions and a full-text review of 447 studies, 82 studies were included in the comprehensive, final review. Twenty-nine studies reported a protective effect of outer layer biodiversity in the development of asthma, wheezing, or allergic sensitization. There were also 16 studies suggesting an effect of outer layer biodiversity on increasing asthma, wheezing, or allergic sensitization. However, there was no clear evidence on the role of inner layer biodiversity in the development of asthma, wheezing, and allergic sensitization (13 studies reported a protective effect and 15 reported evidence of an increased risk). CONCLUSIONS Based on the reviewed literature, a future systematic review could focus more specifically on outer layer biodiversity and asthma. It is unlikely that association with inner layer biodiversity would have enough evidence for systematic review. Based on this comprehensive review, there is a need for population-based longitudinal studies to identify critical periods of exposure in the life course into adulthood and to better understand mechanisms linking environmental exposures and changes in microbiome composition, diversity, and/or function to development of asthma and allergic sensitization. https://doi.org/10.1289/EHP13948.

中文翻译：

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生物多样性在哮喘和过敏性过敏发展中的作用：最新科学回顾。


背景技术 据报道，土地利用的变化和气候变化会减少环境和人类微生物群的生物多样性。生物多样性的减少可能导致免疫调节回路刺激不足和不平衡，并最终导致哮喘和过敏等临床疾病。目的 我们总结了关于生物多样性内层（肠道、皮肤和气道）和外层（空气、土壤、天然水、植物和动物）在哮喘、喘息和过敏性过敏发展中的作用的现有经验证据。方法 我们在 SciVerse Scopus、PubMed MEDLINE 和 Web of Science 中进行了截至 2024 年 3 月 5 日的系统检索，以确定评估生物多样性内层和外层与哮喘、喘息或过敏风险之间关系的相关人类研究。该协议已在 PROSPERO 中注册（CRD42022381725）。结果 总共筛选了 2,419 项研究，在排除和对 447 项研究进行全文审查后，82 项研究纳入全面的最终审查。二十九项研究报告了外层生物多样性对哮喘、喘息或过敏性过敏的发展的保护作用。还有 16 项研究表明外层生物多样性对增加哮喘、喘息或过敏性过敏有影响。然而，没有明确的证据表明内层生物多样性在哮喘、喘息和过敏性过敏发展中的作用（13 项研究报告了保护作用，15 项研究报告了风险增加的证据）。结论 根据文献综述，未来的系统综述可以更具体地关注外层生物多样性和哮喘。 与内层生物多样性的关联不太可能有足够的证据进行系统审查。基于这一全面综述，需要进行基于人群的纵向研究，以确定生命历程中直至成年的关键暴露时期，并更好地了解环境暴露与微生物组组成、多样性和/或功能变化与发育之间的联系机制哮喘和过敏性过敏。 https://doi.org/10.1289/EHP13948。