About 339 million people worldwide are suffering from asthma. We aimed to investigate whether exposure to formaldehyde (FA) is associated with asthma, which could provide clues for preventive and mitigation actions. This article provides a systematic review and meta‐analysis of observational studies to assess the association between indoor FA exposure and the risk of asthma in children and adults. An electronic search of PubMed, Embase, and Web of Science was performed to collect all relevant studies published before January 1, 2020, and a total of 13 papers were included in this meta‐analysis. A random‐effect model was conducted to calculate the pooled odds ratio (OR) between FA exposure and asthma. We found that each 10 µg/m³ increase in FA exposure was significantly associated with a 10% increase in the risk of asthma in children (OR = 1.10, 95% confidence interval = 1.00‐1.21). We sorted the FA concentrations reported in the selected articles and categorized exposure variables into low (FA ≤ 22.5 µg/m³) and high exposure (FA > 22.5 µg/m³) according to the median concentration of FA. In the high‐exposure adult group, FA exposure may also be associated with an increased risk of asthma (OR = 1.81, 95% CI = 1.18‐2.78).

中文翻译：

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室内甲醛暴露与哮喘之间的关联：观察性研究的系统评价和荟萃分析。

全球约有3.39亿人患有哮喘。我们旨在调查甲醛（FA）暴露是否与哮喘有关，这可以为预防和缓解措施提供线索。本文对观察性研究进行了系统的综述和荟萃分析，以评估室内FA暴露与儿童和成人哮喘风险之间的关联。对PubMed，Embase和Web of Science进行了电子检索，以收集2020年1月1日之前发表的所有相关研究，该荟萃分析总共包括13篇论文。进行了随机效应模型以计算FA暴露与哮喘之间的综合优势比（OR）。我们发现每10 µg / m ³FA暴露的增加与儿童哮喘风险增加10％显着相关（OR = 1.10，95％置信区间= 1.00-1.21）。我们对所选文章中报告的FA浓度进行了分类，并根据FA的中值浓度将其暴露变量分为低（FA≤22.5 µg / m ³）和高暴露（FA> 22.5 µg / m ³）。在成人高暴露人群中，FA暴露也可能与哮喘风险增加相关（OR = 1.81，95％CI = 1.18-2.78）。