Abstract

Objective

We aimed to conduct a systematic review examining the association between outdoor pollen and childhood asthma hospitalizations.

Data Source

A systematic search of articles in MEDLINE, EMBASE, CINAHL, ProQuest Central, Web of Science and Google Scholar published to 18 July 2019.

Study selection: Studies that presented data on pollen exposure and childhood asthma hospitalization were included and evaluated for potential risk of bias by two independent authors. Random effects meta-analysis was performed where possible.

Results

A total of 1048 records were identified, and twelve studies included in the review. The synthesis suggested possible associations between outdoor pollen, especially for grass and birch and childhood asthma hospitalization. However, the results varied widely across geographical areas and settings for other pollen taxa. The meta-analysis of the case-crossover studies showed a positive association between grass and childhood asthma hospitalization, an increase in 10 grass pollen grains/m³ was associated with a 3% increase in childhood asthma admission (OR = 1.03; 95%CI:1.01, 1.04), but the pooled estimate was not significant for timeseries studies. The meta-analysis of the timeseries studies for birch pollen showed an increase in 10 pollen grains/m³ being significantly associated with a Mean Percentage Change (MPC) in childhood asthma admissions (MPC= 0.85; 95%CI:0.40, 1.30).

Conclusion: Globally, grass and birch pollen are important triggers of childhood asthma hospitalization, but the association could not be ascertained for other pollen taxa. Pollen is a major environmental trigger of asthma exacerbations and more focus on early interventions to reduce this burden needs to be considered.

摘要

客观的

我们旨在进行系统评价，检查室外花粉与儿童哮喘住院之间的关联。

数据源

系统搜索 MEDLINE、EMBASE、CINAHL、ProQuest Central、Web of Science 和 Google Scholar 中发表至 2019 年 7 月 18 日的文章。

研究选择：包括提供花粉暴露和儿童哮喘住院数据的研究，并由两位独立作者评估潜在的偏倚风险。在可能的情况下进行随机效应荟萃分析。

结果

总共确定了 1048 条记录，其中 12 项研究被纳入该评价。综合表明室外花粉，尤其是草和桦树花粉与儿童哮喘住院之间可能存在关联。然而，结果在其他花粉分类群的地理区域和环境中差异很大。病例交叉研究的荟萃分析显示，草花粉粒/m ^{3 的}增加与儿童哮喘住院率增加 3% 相关（OR = 1.03；95%CI） :1.01, 1.04)，但汇总估计对于时间序列研究并不显着。桦树花粉时间序列研究的荟萃分析显示，10 花粉粒/m ^{3 增加} 与儿童哮喘入院的平均百分比变化 (MPC) 显着相关 (MPC = 0.85; 95% CI:0.40, 1.30)。

结论：在全球范围内，草花和桦树花粉是儿童哮喘住院的重要诱因，但无法确定其他花粉类群的关联。花粉是哮喘发作的主要环境诱因，需要考虑更多地关注早期干预以减少这种负担。