Effects of Inhalation of Thermal Water on Exhaled Breath Condensate in Chronic Obstructive Pulmonary Disease

Abstract

Background: Inhalation of thermal water (TW) is traditionally used as part of the treatment of chronic obstructive pulmonary disease (COPD), but its benefit and mechanisms are controversial. We previously observed a reduced proportion of neutrophils in induced sputum after treatment with TW. Objectives: The aim of this study was to determine whether inhalation of TW in COPD patients is associated with biochemical changes of airway lining fluid, including a reduction in the neutrophil chemoattractant leukotriene B₄ (LTB₄). Methods: Thirteen COPD patients were randomly assigned to receive a 2-week course of TW and normal saline inhalation in a cross-over, single-blind study design. Exhaled breath condensate (EBC) was collected before and after treatments. LTB₄ concentrations in EBC were determined by ELISA, and EBC pH was measured before and after argon deaeration. Results: No significant differences in LTB₄ concentrations in EBC were detected with either treatment. A significant decrease in pH of non-deaerated EBC was observed after a standard course of TW (median 7.45, interquartile range 6.93–7.66, vs. median 6.99, interquartile range 6.57–7.19; p = 0.05), which disappeared after argon deaeration. Conclusions: There is no evidence that TW treatment affects LTB₄ concentration in EBC. The results of EBC pH measurements suggest that TW inhalation induces an imbalance of volatile components of the buffer system in airway lining fluid.