IntroductionSevere bronchiolitis (i.e., bronchiolitis requiring hospitalization) is linked to childhood asthma development. Despite a growing understanding of risk factors for developing post‐bronchiolitis asthma, protective factors remain unclear. In this study, we aimed to investigate whether exposure to residential greenness between birth and bronchiolitis hospitalization is associated with asthma and atopic asthma development by age 6 years.MethodsWe analyzed a US severe bronchiolitis cohort from hospitalization to age 6 years, investigating how the normalized difference vegetation index (NDVI) and chlorophyll index green (CI green), measured in small (100 m) and large (500 m) radiuses around homes, relate to asthma and atopic asthma by age 6 years. We also explored whether maternal antibiotic use, daycare attendance, and respiratory virus type during hospitalization act as effect modifiers.ResultsThe study cohort included 861 infants, with 239 (28%) developing asthma by age 6 years—152 atopic, 17 nonatopic, and 70 unclassified. Early life residential exposure to high NDVI and CI green levels was associated with lower odds of asthma (ORAdj for NDVI within a 100 m radius, 0.18; 95% CI, 0.05–0.78; and ORAdj for CI green levels within a 100 m radius, 0.53; 95% CI, 0.31–0.90). Associations also were significant for the development of atopic asthma (ORAdj 0.16; 95% CI, 0.03–0.96; and ORAdj 0.46; 95% CI, 0.25–0.92; respectively). Results were similar for the 500 m radius exposures. No effect modification was noted.ConclusionIn a U.S. bronchiolitis cohort, exposure to residential greenness between birth and bronchiolitis hospitalization is linked to lower asthma and atopic asthma risk by age 6 years.

中文翻译：

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美国毛细支气管炎队列中早期暴露于住宅绿化和哮喘风险


引言严重的毛细支气管炎（即需要住院治疗的毛细支气管炎）与儿童哮喘的发展有关。尽管对发生毛细支气管炎后哮喘的危险因素的了解越来越多，但保护因素仍不清楚。在这项研究中，我们旨在调查出生和毛细支气管炎住院之间暴露于住宅绿色是否与 6 岁时哮喘和特应性哮喘的发展有关。方法我们分析了从住院到 6 岁的美国严重毛细支气管炎队列，研究了在家庭周围小 （100 m） 和大 （500 m） 半径中测量的标准化差异植被指数 （NDVI） 和绿色叶绿素指数 （CI green） 与哮喘和特应性哮喘的关系到 6 岁。我们还探讨了母亲在住院期间使用抗生素、日托出勤率和呼吸道病毒类型是否起作用调节因素。结果研究队列包括 861 名婴儿，其中 239 名 （28%） 在 6 岁时发展为哮喘——152 名特应性哮喘，17 名非特应性婴儿和 70 名未分类婴儿。早期住宅暴露于高 NDVI 和 CI 绿色水平与较低的哮喘几率相关（100 m 半径内 NDVI 的 ORAdj，0.18;95% CI，0.05-0.78;100 m 半径内的 CI 绿色水平的 ORAdj，0.53;95% CI，0.31-0.90）。相关性对特应性哮喘的发生也具有显著意义（分别为 ORAdj 0.16;95% CI，0.03-0.96;和 ORAdj 0.46;95% CI，0.25-0.92;）。500 m 半径曝光的结果相似。没有发现效果修改。结论在美国毛细支气管炎队列中，出生和毛细支气管炎住院之间暴露于住宅绿色与 6 岁时哮喘和特应性哮喘风险降低有关。