Exhaled breath analysis for the discrimination of asthma and chronic obstructive pulmonary disease

Abstract

Abstract
BACKGROUND Chronic obstructive pulmonary disease (COPD) and asthma are the most common chronic respiratory diseases. In middle-aged and elderly patients, it is difficult to distinguish between COPD and asthma based on clinical symptoms and pulmonary function examinations in clinical practice. Thus, an accurate and reliable inspection method is required.
METHOD In this study, we aimed to identify breath biomarkers and evaluate the accuracy of breathomics-based methods for discriminating between COPD and asthma. In this multi-center cross-sectional study, exhaled breath samples were collected from 89 patients with COPD and 73 with asthma and detected on a high-pressure photon ionization time-of-flight mass spectrometry (HPPI-TOFMS) platform from October 20, 2022, to May 20, 2023, in four hospitals. Data analysis was performed from June 15, 2023, to August 16, 2023. The sensitivity, specificity, and accuracy were calculated to assess the overall performance of the VOC-based COPD and asthma discrimination models. Potential VOC markers related to COPD and asthma were also analyzed. 
RESULTS The age of all participants ranged from to 18-86 years, and 54 (33.3%) were men. Based on breathomics feature selection, ten VOCs were identified as COPD and asthma discrimination biomarkers via breath testing. The joint panel of these ten VOCs achieved an area under the curve (AUC) of 0.843, sensitivity of 75.9%, specificity of 87.5%, and accuracy of 80.0% in COPD and asthma discrimination. Furthermore, the VOCs detected in the breath samples were closely related to the clinical characteristics of COPD and asthma.
CONCLUSIONS The VOC-based COPD and asthma discrimination model showed good accuracy, providing a new strategy for clinical diagnosis. Breathomics-based methods may play an important role in the diagnosis of COPD and asthma.