EXhaled Hydrogen peroxide As a marker of Lung diseasE – the EXHALE 1A study

Background: Inflammacheck™ is a new point-of-care (POC) device measuring exhaled breath temperature, humidity, and hydrogen peroxide (H2O2); the latter a marker of oxidative stress in the airways. Method: Using Inflammacheck™, we assessed levels of H2O2 in exhaled breath condensate (EBC) obtained during 60 seconds of tidal breathing in participants with stable asthma or COPD, and healthy controls. We also explored the effect of patient factors on H2O2 levels (e.g. time of last meal) and assessed device acceptability by questionnaire. Results: We recruited 177 partcipants (67 asthma [32 GINA 2/3, 34 GINA 4/5], 60 COPD [30 GOLD stages 1/2, 30 GOLD 3/4] and 50 controls. Data from 153 partcipants was analysed. Compared to healthy controls, mean EBC H2O2 levels were significantly higher in participants with COPD (2.55 μM vs 3.17 μM, p Conclusion: Compared to healthy controls EBC H2O2 levels were significantly higher in asthma and COPD, and the Inflammacheck™ device may prove a useful POC diagnostic tool. This study was funded by Asthma UK (AUK-IG-2016-357).