A systematic review of research examining exhaled volatile organic compound (VOC) biomarkers for adult asthma has highlighted our ReCIVA® Breath Sampler, the heart of the Breath Biopsy® platform, as a potential optimal solution to some of the persistent challenges of standardized breath collection encountered within the field.
The review, Azim et al. , looked at 66 papers and analysed data from 22. The papers examine a range of applications including asthma diagnosis, phenotyping, treatment stratification, treatment monitoring and exacerbation prediction. Methodologies vary widely across the publications including varous breath manoevres, breath fractions, breath collection tools and both e-nose and GC-MS analysis methods.
As with our recent blog, the discussion of the review focuses on the persistent key challenges in the field and highlights the difficulties in comparing between publications that use such diverse approaches. The challenge encompasses the need to improve reference libraries for breath VOCs, the complexities of collecting volatile compounds, and the issues of collecting total breath fractions. The authors also explore the various attempts that have been made to consistently fractionate breath samples to produce cleaner, clearer results. It is in this respect that they highlight the ReCIVA Breath Sampler, a product of the Breathe Free consortium of experts:
"The optimal solution needs to balance practicality and precision, so as not to negate the clinical utility of breath sampling. The breath sampler developed by a broad consortium of breath researchers and engineers (http://www.breathe-free.org), represents one such solution."
The paper also examines the many data analysis approaches that have been applied in breath research, a challenge that we are seeking to address through our Breath Biopsy Services which apply our expertise in breath collection and VOC detection to developing and implementing suitable data analysis pipelines for breath biomarker data.
The authors conclude with the view that, across all the studies, it is apparent that there is potential for VOCs to reflect inflammation responses in asthma and that breath testing could be applied to the discrimination of asthma phenotypes. They expound the need for larger samples sizes, robust study design and greater independent validation of results to support the existing studies and to consolidate the potential of breathomics into clinical applications. Earlier this year we highlighted a study that used extensive independent validation to develop robust models for distinguising asthma phenotypes, setting a clear example for future development in the field.
You can find out more about the applications of Breath Biopsy in the asthma field by reading our case study or by expressing your interest in attending the Breath Biopsy Conference in Cambridge, UK this November.
- Azim et al. (2019) Exhaled volatile organic compounds in adult asthma: a systematic review. Eur Respir J. DOI: 10.1183/13993003.00056-2019