JPD: Exhaled gas analysis of patients with Parkinson's disease, helpful for disease diagnosis and classification

With significant advances in the understanding of the underlying biological mechanisms of Parkinson's disease (PD), improvements in clinical diagnosis, stratification, and long-term monitoring of the disease remain key areas for further investigation
.

These questions become even more relevant as more and more clinical trials are conducted in search of potentially disease-modifying treatments

In addition, numerous longitudinal studies have also demonstrated significant heterogeneity in disease progression rates and clinical characteristics in PD populations
.

Therefore, while efforts are made to move towards more personalized and targeted PD therapy, better methods for diagnosing, evaluating, and monitoring PD patients are urgently needed

Extensive collaborative efforts are currently underway to identify biomarkers that can achieve this goal
.

However, many of these investigations involve invasive methods (such as lumbar puncture analysis of cerebrospinal fluid), do not provide immediate clinical feedback, and often involve specialized laboratory-based analysis and/or methods that are expensive and uncomfortable for the patient (such as MRI) or PET imaging)

Therefore, any new biomarker method for assessing PD patients, including methods that are rapid, easy to use and non-invasive, would have clear advantages
.

One way is by analyzing the breathing of patients with the disease

In this regard, the analysis of volatile organic compounds (VOCs) in breath has led to the development of technologies that can be used to identify, screen and longitudinally monitor chronic diseases such as PD
.

This approach has been successfully tested preclinically in neurotoxin-based PD models and transgenic PD models

With this, Simon Stotta et al.
, University of Cambridge, sought to extend these findings by studying a large, well-characterized clinical cohort of PD patients to determine whether the analysis of VOCs in breath samples could be used
.

1) confirm its diagnostic utility, including feasibility; 2) stage the disease; and 3) provide new or confirm established mechanistic insights into the condition

They collected breath samples from 177 PD patients and 37 healthy matched controls and followed them long-term
.

Standard clinical data (MDS-UPDRS and cognitive assessments) of PD patients were also collected at the same time as breath samples were collected, and these measures were then correlated with breath test analysis of exhaled VOCs

They found that breath testing was able to distinguish PD patients from healthy control participants and correlated with disease stage
.

The offline system (remote analysis) gave good results, with overall classification accuracy ranging from 73.

Breath testing distinguishes PD patients from healthy control participants and correlates with disease stage

Online (clinic) systems showed similar results, but with lower correlations ranging from 33.
5% to 82.
4%
.
Chemical analysis identified 29 distinct potential molecules that may be involved in the pathogenic pathways of PD
.

The significance of this study is the discovery that breath analysis shows potential for PD diagnosis and monitoring
.
Both off-line and on-line sensor systems are easy to operate and provide comparable results, which, if larger-scale studies corroborate our findings, will make this technology readily available for clinical adoption
.

Breath analysis shows potential for PD diagnosis and monitoring

Original source:
Stott S, Broza YY, Gharra A, Wang Z, Barker RA, Haick H.
The Utility of Breath Analysis in the Diagnosis and Staging of Parkinson's Disease.
_JPD_.
Published online February 8, 2022:1-10.
doi: [10.
3233/JPD-213133](https://doi.
org/10.
3233/JPD-213133)

leave a message here