DSP as a Predictor in Pulmonary Hypertension
Research type
Research Study
Full title
Distance Saturation Product as an Outcome Predictor in Idiopathic Pulmonary Arterial Hypertension
IRAS ID
310189
Contact name
Colin Church
Contact email
Sponsor organisation
NHS National Waiting Times Centre
Duration of Study in the UK
0 years, 4 months, 1 days
Research summary
Pulmonary Hypertension (PH) is a rare, progressive disease characterised by increased pressure in the pulmonary arteries. The disease is categorised into five sub-groups; Idiopathic pulmonary arterial hypertension (IPAH) belongs to Group I (pulmonary arterial hypertension). IPAH causes progressive narrowing of the pulmonary arteries, increasing resistance and pressure which eventually manifests as heart failure and premature death.
Exercise intolerance is a hallmark symptom of IPAH and assessment of patients’ functional exercise capacity is fundamental in their evaluation and ongoing monitoring. To assess exercise capacity, patients undergo the six-minute walk test (6MWT). Patients are asked to walk the maximum distance they can in six minutes, whilst monitoring oxygen saturations throughout.
The 6MWT is a primary outcome in the majority of clinical trials in PH and walking distance is used as a prognostic indicator in PAH by the European Society of Cardiology. However, analyses of the predictive value of 6-minute-walk-distance (6MWD) have found it to be a poor predictor of clinical outcomes in PH.
The distance saturation product (DSP) is a novel measure of 6MWT performance, that includes surveillance of both distance covered and the lowest oxygen saturation of patients during the test. Analyses into the prognostic value of the DSP in other respiratory diseases, such as non-CF bronchiectasis, have suggested the DSP is an effective predictor of mortality. A retrospective analysis of a cohort of patients with idiopathic pulmonary fibrosis found the DSP strongly correlated with outcome measures. No studies to our knowledge have previously investigated the distance-saturation product (DSP) of 6MWT to predict the prognosis of patients with IPAH.
Using retrospective data, this study aims to determine whether DSP could provide a simple measurement to (i) offer prognostic information for patients and (ii) correlate with routinely collected outcome measures.
REC name
London - City & East Research Ethics Committee
REC reference
22/PR/0413
Date of REC Opinion
13 Apr 2022
REC opinion
Favourable Opinion