Monitoring patients with chronic, inflammatory airways disease particularly in the early stages is hampered by the relative insensitivity of current outcome measures to detect subtle changes. Multiple breath washout is a potential sensitive test that is a useful readout of disease at these early stages but it lacks standardisation and knowledge of variability with reference to standard lung function measures. This is a Cross sectional and longitudinal observation study. The hypothesis is that multiple breath washout-derived indices will provide a robust signal of gas mixing inhomogeneity, correlating with conventional measures of airway disease severity. Multiple breath washout performed on different devices will generate indices which correlate but differ in value.

Population

Patients aged two and upwards with chronic airways disease including CF, PCD, Asthma and Bronchiectasis, Persistent bacterial bronchitis and sleep disordered breathing and obesity as well as aged matched healthy control patients will be approached to take part in the study. Healthy volunteers will only complete MBW and Spirometry for comparison with respiratory disease patients.

Brief Title

Multiple Breath Washout, a Clinimetric Dataset

Official Title

Multiple Breath Washout in Paediatric Chronic Airways Disease: Building a Clinimetrics Dataset

Brief Summary

Monitoring patients with chronic, inflammatory airways disease particularly in the early<br /> stages is hampered by the relative insensitivity of current outcome measures to detect subtle<br /> changes. Multiple breath washout is a potential sensitive test that is a useful readout of<br /> disease at these early stages but it lacks standardisation and knowledge of variability with<br /> reference to standard lung function measures. This is a Cross sectional and longitudinal<br /> observation study. The hypothesis is that multiple breath washout-derived indices will<br /> provide a robust signal of gas mixing inhomogeneity, correlating with conventional measures<br /> of airway disease severity. Multiple breath washout performed on different devices will<br /> generate indices which correlate but differ in value.

Detailed Description

Lung Clearance Index (LCI) has been shown to be more sensitive and perhaps more applicable in
early stages of lung disease when compared to currently utilised physiological outcome
measures, and yet it is not approved by regulatory agencies as a recognised surrogate outcome
measure. This may highlight some of the lack of understanding within MBW; what is the best
equipment to use, what is the minimal value of change to show an improvement in LCI, what is
LCI's correlation with clinical outcome measures and what does the progression of LCI tell us
about lung disease. These questions will be addressed with a view to contributing a body of
data to guide decisions around its utility in both interventional drug trials and for
monitoring in a clinical setting.

The aim of this study is to assess the suitability of LCI as a clinical outcome measure for
both clinical trials and clinical monitoring of patients with inflammatory respiratory
disease across the disease spectrum. Different testing modalities will be compared as well as
assess the repeatability and validity of LCI for its determination as an outcome measure.
Long-term follow up will allow an assessment of the relationship between LCI and future
outcomes such as rate of decline in lung function and frequency of exacerbations, both
recognised as relevant by regulatory agencies.

Outcome Measures

Outcome measures are the tests that investigators perform to prove whether or not a treatment being tested in a clinical trial is having any effect.