Аннотация: Background
Exhaled breath analysis is one of promising methods of non-invasive monitoring of pulmonary disease. According to results of previous researches cigarette smoking influences on composition of exhaled breath either patients with COPD or healthy people.
Objective: Aim of our study was to assess effects of smoking on the exhaled breath.
Methods
We used measure based on Mahalanobis distance for biomedical analysis. This distance gives the opportunity to separate absorption spectra of breath air of patients with COPD from absorption spectra of breath air of healthy volunteers. The specific average square of the Mahalanobis distances of exhaled air absorption spectra was calculated in the 10P and 10R spectral bands of CO2 laser generation.
Results
The analysis of exhaled air absorption spectrum revealed a significant difference (p) between patients with COPD and healthy volunteers only in the 10P spectral band. While the absorption spectrum of exhaled air non-smoking healthy volunteers significantly differed between patients with COPD (p<0.001) in the 10P and 10R spectral band.
By analyzing exhaled air COPD can be expected in 70% of cases when Mahalanobis distance is more than 1.28 in comparing patients with COPD and healthy volunteers. When comparing patients with COPD and non-smoking healthy volunteers accuracy of COPD diagnostic increases to 89%
Conclusion
Smoking has a significant impact on composition of exhaled breath healthy people that have to be considered during COPD diagnosis by analyzing the exhaled air using opto-acoustic spectroscopy.