Related Experiment Video
Updated: Jun 1, 2026

Breath Collection from Children for Disease Biomarker Discovery
Published on: February 14, 2019
Exhaled breath condensate pH as a biomarker of COPD severity in ex-smokers
Andriana I Papaioannou1, Stelios Loukides, Markos Minas
1Respiratory Medicine Department, University of Thessaly Medical School, Larissa, Greece.
Abstract:
Endogenous airway acidification, as assessed by exhaled breath condensate (EBC) pH, is present in patients with stable COPD. The aim of this study was to measure EBC pH levels in a large cohort of COPD patients and to evaluate associations with functional parameters according to their smoking status.EBC was collected from 161 patients with stable COPD and 112 controls (current and ex-smokers). EBC pH was measured after Argon deaeration and all subjects underwent pulmonary function testing.EBC pH was lower in COPD patients compared to controls [7.21 (7.02, 7.44) vs. 7.50 (7.40, 7.66); p < 0.001] and ex-smokers with COPD had lower EBC pH compared to current smokers [7.16 (6.89, 7.36) vs 7.24 (7.09, 7.54), p = 0.03]. In ex-smokers with COPD, EBC pH was lower in patients with GOLD stage III and IV compared to patients with stage I disease (p = 0.026 and 0.004 respectively). No differences were observed among current smokers with different disease severity. EBC pH levels in ex-smokers were associated with static hyperinflation (as expressed by IC/TLC ratio), air trapping (as expressed by RV/TLC ratio) and diffusing capacity for carbon monoxide, whereas no associations were observed in current smokers.Endogenous airway acidification is related to disease severity and to parameters expressing hyperinflation and air trapping in ex-smokers with COPD. The possible role of EBC pH in COPD needs to be further evaluated in longitudinal studies.
More Related Videos
08:23Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
Published on: March 9, 2018
09:19Capturing Actively Produced Microbial Volatile Organic Compounds from Human-Associated Samples with Vacuum-Assisted Sorbent Extraction
Published on: June 1, 2022
Related Concept Videos
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features
Chronic Obstructive Pulmonary Disease-I: Introduction
Chronic Obstructive Pulmonary Disease II: Emphysema
Chronic Obstructive Pulmonary Disease IV: Clinical Manifestations
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...