A Comparative Assessment of Measurements Made in an Incremental Shuttle Walk Test and Incremental Cycle Ergometry Test in Patients With Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic and potentially fatal lung disease. As IPF progresses, patients become increasingly breathless with reduced exercise capacity and quality of life. Average life expectancy is three years from diagnosis but IPF progresses at different rates in different people. In 2012 the British Lung Foundation estimated that 32,500 in the UK had IPF.

An accurate prognosis can help determine the most appropriate individual treatment option and allow patients and their families to make suitable plans. Currently, measurements from resting lung function tests are used to predict prognosis. However, measurement made during CPET are more sensitive survival predictors and CPET is the gold standard test to assess prognosis in IPF. A CPET test is relatively time-consuming and requires specialist equipment that is not universally available. CPET is not routinely used in clinical practice for the assessment of IPF.

The incremental shuttle walk test (ISWT) is quicker, cheaper and more widely available than CPET. This study builds on previous research done by the Respiratory team which showed a linear relationship between the distance walked in an ISWT and peak oxygen consumption during a CPET, a useful prognostic predictor, in patients with interstitial lung disease. 40-50 patients with IPF will be recruited and will undertake both ISWT and CPET at University Hospital, Coventry. The investigators will compare the results in the current cohort to those of the previous study.

Additionally, the research team will compare oxygen pressure in capillary blood at the end of an ISWT and a CPET. The investigators will also compare patient experience of the two tests using questionnaires. This study paves the way for a simple, standardised test to more accurately predict prognosis in IPF.