Abstract：
BACKGROUND: Globally, observational studies have demonstrated an association between high levels of air pollution and asthma attacks in children. It remains unclear whether and to what extent exposure may be associated with increased near-fatal/fatal attacks.
OBJECTIVE: To systematically review the evidence for an association between ambient outdoor air pollution and fatal and/or near-fatal asthma (NFA).
METHODS: Following Cochrane methodology, we searched MEDLINE, EMBASE, Web of Science, Scopus, and Open Grey electronic databases for studies reporting the association of fatal/NFA and air pollution (particulate matter [PM], sulfur dioxide, nitrogen dioxide, black carbon and ozone [O3]) in children. NFA was defined as requiring intensive care unit (ICU) management.
RESULTS: Two reviewers independently screened 1358 papers. A total of 276 studies identified asthma attacks related to air pollution, 272 did not meet inclusion criteria after full-text review. Four observational studies described fatal/NFA, of which three addressed NFA. PM2.5 (per 12.5 µg/m3 increase) and O3 (per 22 ppb increase) were associated with NFA in one study (PM2.5, relative risk: 1.26, confidence interval [CI] [1.10-1.44]), O3 (1.19 [1.01-1.40]). PM10 was associated with ICU admission in the context of thunderstorm asthma. Elemental carbon was associated equally with NFA that did not require an ICU admission (p = 0.67). Studies of fatal asthma including children did not demarcate age within the analysis.
CONCLUSIONS: Ozone and PM2.5 have been associated with NFA in children but synthesis is limited by the paucity of studies and methodological heterogeneity. Poor reporting of severities of asthma attacks hinders the assessment of whether outdoor air pollution is associated with an increased number of NFA/fatal attacks in children.
OBJECTIVE: To systematically review the evidence for an association between ambient outdoor air pollution and fatal and/or near-fatal asthma (NFA).
METHODS: Following Cochrane methodology, we searched MEDLINE, EMBASE, Web of Science, Scopus, and Open Grey electronic databases for studies reporting the association of fatal/NFA and air pollution (particulate matter [PM], sulfur dioxide, nitrogen dioxide, black carbon and ozone [O3]) in children. NFA was defined as requiring intensive care unit (ICU) management.
RESULTS: Two reviewers independently screened 1358 papers. A total of 276 studies identified asthma attacks related to air pollution, 272 did not meet inclusion criteria after full-text review. Four observational studies described fatal/NFA, of which three addressed NFA. PM2.5 (per 12.5 µg/m3 increase) and O3 (per 22 ppb increase) were associated with NFA in one study (PM2.5, relative risk: 1.26, confidence interval [CI] [1.10-1.44]), O3 (1.19 [1.01-1.40]). PM10 was associated with ICU admission in the context of thunderstorm asthma. Elemental carbon was associated equally with NFA that did not require an ICU admission (p = 0.67). Studies of fatal asthma including children did not demarcate age within the analysis.
CONCLUSIONS: Ozone and PM2.5 have been associated with NFA in children but synthesis is limited by the paucity of studies and methodological heterogeneity. Poor reporting of severities of asthma attacks hinders the assessment of whether outdoor air pollution is associated with an increased number of NFA/fatal attacks in children.
摘要：
背景：在全球范围内，观察性研究表明，高水平的空气污染与儿童哮喘发作之间存在关联。目前尚不清楚暴露是否以及在多大程度上可能与近致命/致命攻击增加有关。
目的：系统评价室外环境空气污染与致命性和/或近致命性哮喘（NFA）相关的证据。
方法：遵循Cochrane方法，我们搜索了MEDLINE,EMBASE,WebofScience,Scopus,和开放灰色电子数据库，用于报告致命/NFA和空气污染(颗粒物[PM]，二氧化硫,二氧化氮,儿童的黑碳和臭氧[O3]）。NFA被定义为需要重症监护病房(ICU)管理。
结果：两位评审员独立筛选了1358篇论文。共有276项研究确定了与空气污染有关的哮喘发作，272在全文审查后不符合纳入标准。四项观察性研究描述了致命/NFA，其中三人解决了NFA。在一项研究中，PM2.5（每增加12.5µg/m3）和O3（每增加22ppb）与NFA相关（PM2.5，相对风险：1.26，置信区间[CI][1.10-1.44]），O3(1.19[1.01-1.40])。在雷暴哮喘的情况下，PM10与ICU入院有关。元素碳与不需要入住ICU的NFA同等相关(p=0.67)。对包括儿童在内的致命性哮喘的研究未在分析中划定年龄。
结论：臭氧和PM2.5与儿童NFA相关，但由于缺乏研究和方法学异质性，综合研究受到限制。哮喘发作严重程度的不良报告阻碍了对室外空气污染是否与儿童NFA/致命发作数量增加有关的评估。
目的：系统评价室外环境空气污染与致命性和/或近致命性哮喘（NFA）相关的证据。
方法：遵循Cochrane方法，我们搜索了MEDLINE,EMBASE,WebofScience,Scopus,和开放灰色电子数据库，用于报告致命/NFA和空气污染(颗粒物[PM]，二氧化硫,二氧化氮,儿童的黑碳和臭氧[O3]）。NFA被定义为需要重症监护病房(ICU)管理。
结果：两位评审员独立筛选了1358篇论文。共有276项研究确定了与空气污染有关的哮喘发作，272在全文审查后不符合纳入标准。四项观察性研究描述了致命/NFA，其中三人解决了NFA。在一项研究中，PM2.5（每增加12.5µg/m3）和O3（每增加22ppb）与NFA相关（PM2.5，相对风险：1.26，置信区间[CI][1.10-1.44]），O3(1.19[1.01-1.40])。在雷暴哮喘的情况下，PM10与ICU入院有关。元素碳与不需要入住ICU的NFA同等相关(p=0.67)。对包括儿童在内的致命性哮喘的研究未在分析中划定年龄。
结论：臭氧和PM2.5与儿童NFA相关，但由于缺乏研究和方法学异质性，综合研究受到限制。哮喘发作严重程度的不良报告阻碍了对室外空气污染是否与儿童NFA/致命发作数量增加有关的评估。
