Exhaled Breath Condensate Biomarkers and Cough in IPF

This study will aim to investigate the levels of the reactive oxygen species (ROS) 8-isoprostane in idiopathic pulmonary fibrosis patients' exhaled breath condensate (EBC). EBC samples will be collected using RTube, prior to analysis for levels of 8-isoprostane. An acceptability assessment will be performed for this non-invasive method of EBC collection through a non-validated questionnaire.

A regression analysis will then be performed for 8-isoprostane levels against the severity of the patient's cough, assessed through the use of the visual analogue scale for cough (VAS), the King's brief interstitial lung disease questionnaire (KBILD), the Medical Research Council (MRC) dyspnoea scale and the Leicester cough questionnaire. Alongside this an exploratory comparison of cough scores and 8 isoprostane concentration between patients with and without honeycombing and traction bronchiectasis.

Inclusion criteria

• Male or female above the age of 40
• IPF diagnosed by a multi-disciplinary team meeting following review of clinical history, thoracic high resolution computed tomography (HRCT) and/or surgical lung according to international guidelines

Exclusion criteria

• A recognised significant co-existing respiratory disease, defined as a respiratory condition that exhibits a clinically relevant effect on respiratory symptoms and disease progression as determined by the principal investigator following multi-disciplinary discussion. For example, patients with bronchiectasis will only be included if the bronchiectasis is deemed to be traction bronchiectasis as a result of idiopathic pulmonary fibrosis
• Airflow obstruction defined as a forced expiratory volume at one second over forced vital capacity (FEV1/FVC) <60% predicted or a residual volume greater than 120% predicted
• Significant medical ,surgical or psychiatric disease that in the opinion of the patient's attending physician would exhibit a clinically relevant effect on the patient's health related quality of life
• The patient is unable to provide written informed consent