Prediction and prognostication in interstitial lung disease associated pulmonary hypertension using baseline and longitudinal trends in non-invasive variables
File(s)
Author(s)
Bax, Simon
Type
Thesis
Abstract
Pulmonary hypertension (PH) commonly occurs in patients with interstitial lung disease
(ILD) and is associated with worsening of symptoms and an adverse prognosis. The onset of
PH is extremely difficult to predict due to the very similar symptomology of the two
conditions and confounding of common screening tests for PH in patients with ILD. It is not
clear what invasive and non-invasive variables predict mortality in ILD-PH patients, or
whether existing mortality prediction tools used in ILD patients are valid in ILD-PH. I
hypothesised that the prediction of PH occurring in ILD patients was possible using non
invasive screening tests, and that baseline and longitudinal change in non-invasive variables
would predict mortality in ILD-PH patients.
The integration of echocardiographic, brain natriuretic peptide (BNP), pulmonary function
tests and CT variables showed that prediction of PH occurring in ILD patients was possible,
although false positives were common. Echocardiographic variables best correlated with
invasive right heart catheter (RHC) pressures. A score was developed to predict severe PH
using echocardiographic variables, and was effective even when blinding the most powerful
predictor which is commonly unavailable in patients with ILD-PH.
CT is commonly employed in suspected ILD-PH patients to exclude co-existent pulmonary
emboli and assess parenchymal disease progression. The right ventricle to left ventricle
measured at CT pulmonary angiography was superior to both echocardiographic and RHC
derived variables at predicting mortality.
The presence of PH confounds commonly used mortality prediction tools in ILD. A multi
modality mortality prediction model was developed to predict mortality using baseline
demographics, lung function and ILD diagnosis. Longitudinal change in pulmonary function
tests and BNP were shown to predict mortality. A longitudinal model using demographics
and change in gas transfer was developed. External validation of the mortality prediction
tools is necessary before its utility is demonstrated.
(ILD) and is associated with worsening of symptoms and an adverse prognosis. The onset of
PH is extremely difficult to predict due to the very similar symptomology of the two
conditions and confounding of common screening tests for PH in patients with ILD. It is not
clear what invasive and non-invasive variables predict mortality in ILD-PH patients, or
whether existing mortality prediction tools used in ILD patients are valid in ILD-PH. I
hypothesised that the prediction of PH occurring in ILD patients was possible using non
invasive screening tests, and that baseline and longitudinal change in non-invasive variables
would predict mortality in ILD-PH patients.
The integration of echocardiographic, brain natriuretic peptide (BNP), pulmonary function
tests and CT variables showed that prediction of PH occurring in ILD patients was possible,
although false positives were common. Echocardiographic variables best correlated with
invasive right heart catheter (RHC) pressures. A score was developed to predict severe PH
using echocardiographic variables, and was effective even when blinding the most powerful
predictor which is commonly unavailable in patients with ILD-PH.
CT is commonly employed in suspected ILD-PH patients to exclude co-existent pulmonary
emboli and assess parenchymal disease progression. The right ventricle to left ventricle
measured at CT pulmonary angiography was superior to both echocardiographic and RHC
derived variables at predicting mortality.
The presence of PH confounds commonly used mortality prediction tools in ILD. A multi
modality mortality prediction model was developed to predict mortality using baseline
demographics, lung function and ILD diagnosis. Longitudinal change in pulmonary function
tests and BNP were shown to predict mortality. A longitudinal model using demographics
and change in gas transfer was developed. External validation of the mortality prediction
tools is necessary before its utility is demonstrated.
Version
Open Access
Date Issued
2019-10
Date Awarded
2020-12
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Wort, Stephen John
Sponsor
Imperial College London
Grant Number
None
Publisher Department
National Heart & Lung Institute
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Medicine (Research) MD (Res)