Biomarkers in adult asthma: a systematic review of 8-isoprostane in exhaled breath condensate

J Breath Res. 2017 Feb 10;11(1):016011. doi: 10.1088/1752-7163/aa5a8a.


Objectives: We aimed to assess the evidence for the use of 8-isoprostane in exhaled breath condensate (EBC) as a biomarker in adult asthma.

Design: A systematic review and meta-analysis of EBC 8-isoprostane.

Methods: We searched a number of online databases (including PubMed, Embase and Scopus) in January 2016. We included studies of adult non-smokers with EBC collection and asthma diagnosis conducted according to recognised guidelines. We aimed to pool data using random effects meta-analysis and assess heterogeneity using I 2.

Results: We included twenty studies, the findings from which were inconsistent. Seven studies (n = 329) reported 8-isoprostane levels in asthma to be significantly higher than that of control groups, whilst six studies (n = 403) did not. Only four studies were appropriate for inclusion in a random effects meta-analysis of mean difference. This found a statistically significant between-groups difference of 22 pg ml-1. Confidence in the result is limited by the small number of studies and by substantial statistical heterogeneity (I 2 = 94).

Conclusion: The clinical value of EBC 8-isoprostane as a quantitative assessment of oxidative stress in asthma remains unclear due to variability in results and methodological heterogeneity. It is essential to develop a robust and standardised methodology if the use of EBC 8-isoprostane in asthma is to be properly evaluated.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Adult
  • Asthma / diagnosis*
  • Biomarkers / analysis
  • Breath Tests / methods*
  • Case-Control Studies
  • Dinoprost / analogs & derivatives*
  • Dinoprost / analysis
  • Exhalation*
  • Humans


  • Biomarkers
  • 8-epi-prostaglandin F2alpha
  • Dinoprost