Using the Inflammacheck Device to Measure the Level of Exhaled Breath Condensate Hydrogen Peroxide in Patients With Asthma and Chronic Obstructive Pulmonary Disease (The EXHALE Pilot Study): Protocol for a Cross-Sectional Feasibility Study

Abstract

Background: Asthma and Chronic Obstructive Pulmonary Disease (COPD) are common conditions that affect over 5 million people in the United Kingdom. These groups of patients suffer significantly from breathlessness and recurrent exacerbations that can be difficult to diagnose and go untreated. A common feature of COPD and asthma is airway inflammation that increases before and during exacerbations. Current methods of assessing airway inflammation can be invasive, difficult to perform, and are often inaccurate. In contrast, measurement of exhaled breath condensate (EBC) hydrogen peroxide (H₂O₂) is performed during normal tidal breathing and is known to reflect the level of global inflammation in the airways. There is a need for novel tools to diagnose asthma and COPD earlier and to detect increased airway inflammation that precedes an exacerbation.

Objective: The aim of this study was to explore the use of a new handheld device (called Inflammacheck) in measuring H₂O₂ levels in EBC. We will study whether it can measure EBC H₂O₂ levels consistently and whether it can be used to differentiate asthma and COPD from healthy controls.

Methods: We will perform a cross-sectional, feasibility, pilot study of EBC H₂O₂ levels, as measured by Inflammacheck, and other markers of disease severity and symptom control in patients with asthma and COPD and volunteers with no history of lung disease. Participants will be asked to provide an exhaled breath sample for measurement of their EBC H₂O₂ using Inflammacheck. The result will be correlated with disease stage, spirometry, fractional exhaled nitric oxide (FeNO), and symptom control scores.

Results: This study's recruitment is ongoing; it is anticipated that the results will be available in 2018.

Conclusions: The EXhaled Hydrogen peroxide As a marker of Lung diseasE (EXHALE) pilot study will provide an evaluation of a new method of measuring EBC H₂O₂. It will assess the device's consistency and ability to distinguish airway inflammation in asthma and COPD compared with healthy controls.

Keywords: COPD; asthma; biomarkers; medical device; reexhalation.

Figure 1

Summary of study procedures and the participant flow. COPD: Chronic Obstructive Pulmonary Disease; QAH: Queen Alexandra Hospital; PIS: participant information sheet; QoL: quality of life; ACQ: asthma control questionnaire; AQLQ: asthma quality of life questionnaire; CAT: COPD assessment test; SPT: skin prick test; EBC H₂O₂: exhaled breath condensate hydrogen peroxide; FeNO: fractional exhaled nitric oxide.