Background

Metabolomics refers to study of the metabolome, the entire set of metabolites produced by a biological system. The application of metabolomics to exhaled breath samples - breathomics - is a rapidly growing field with potential application to asthma diagnosis and management.

Objectives

We aimed to review the adult asthma breathomic literature and present a comprehensive list of volatile organic compounds identified by asthma breathomic models.

Methods

We undertook a systematic search for literature on exhaled volatile organic compounds in adult asthma. We assessed the quality of studies and performed a qualitative synthesis.

Results

We identified twenty studies; these were methodologically heterogenous with a variable risk of bias. Studies almost universally reported breathomics to be capable of differentiating - with moderate or greater accuracy - between samples from healthy controls and those with asthma; and to be capable of phenotyping disease. However, there was little concordance in the compounds upon which discriminatory models were based.

Conclusion

Results to-date are promising but validation in independent prospective cohorts is needed. This may be challenging given the high levels of inter-individual variation. However, large-scale, multi-centre studies are underway and validation efforts have been aided by the publication of technical standards likely to increase inter-study comparability. Successful validation of breathomic models for diagnosis and phenotyping would constitute an important step towards personalised medicine in asthma.

中文翻译：

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与哮喘的诊断和疾病特征相关的挥发性有机化合物-系统评价。

背景

代谢组学是指研究代谢组，即由生物系统产生的整套代谢产物。代谢组学在呼气样品中的应用-呼吸组学-是一个快速发展的领域，潜在地应用于哮喘的诊断和治疗。

目标

我们旨在回顾成人哮喘呼吸道文献，并提供由哮喘呼吸道模型鉴定出的挥发性有机化合物的完整列表。

方法

我们对成年哮喘中呼出的挥发性有机物进行了系统的文献检索。我们评估了研究质量并进行了定性综合。

结果

我们确定了二十项研究；这些方法在方法上是异质的，存在偏见的风险。几乎所有研究都普遍报道，呼吸定律能够以中等或更高的准确度区分健康对照和哮喘患者的样本。并能够对疾病进行表型分析。但是，判别模型所基于的化合物几乎没有一致性。

结论

迄今为止的结果令人鼓舞，但需要在独立的前瞻性队列中进行验证。鉴于个人之间的差异很大，这可能具有挑战性。但是，正在进行大规模，多中心的研究，并且通过可能会提高研究间可比性的技术标准的发布帮助进行了验证工作。成功地验证用于诊断和表型的呼吸系统模型将是迈向哮喘个性化医学的重要一步。