TY - JOUR
T1 - Idiopathic pulmonary fibrosis
T2 - A composite physiologic index derived from disease extent observed by computed tomography
AU - Wells, Athol U.
AU - Desai, Sujal R.
AU - Rubens, Michael B.
AU - Goh, Nicole S.L.
AU - Cramer, Derek
AU - Nicholson, Andrew G.
AU - Colby, Thomas V.
AU - Du Bois, Roland M.
AU - Hansell, David M.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/4/1
Y1 - 2003/4/1
N2 - In idiopathic pulmonary fibrosis, the quantitation of disease severity using pulmonary function tests is often confounded by emphysema. We have identified the composite physiologic index (CPI) most closely reflecting the morphologic extent of pulmonary fibrosis. Consecutive patients with a clinical/computed tomography (CT) diagnosis of idiopathic pulmonary fibrosis (n = 212) were divided into group I (n = 106) and group II (n = 106). The CPI was derived in group I (by fitting pulmonary function tests against disease extent on CT) and was tested in Group II. The formula for the CPI was as follows: extent of disease on CT = 91.0 - (0.65 × percent predicted diffusing capacity for carbon monoxide [DLCO]) - (0.53 × percent predicted FVC) + (0.34 × percent predicted FEV1). In group II, the CPI correlated more strongly with disease extent on CT (r2 = 0.51) than the individual pulmonary function test (DLCO the highest value, r2 = 0.38). A subanalysis demonstrated that the better fit of the CPI was ascribable to a correction of the confounding effects of emphysema. Mortality was predicted more accurately by the CPI than by a pulmonary function test in all clinical subgroups, including a separate cohort of 36 patients with histologically proven usual interstitial pneumonia (CPI, p < 0.0005; FVC, p = 0.002; Po2, p = 0.002). In conclusion, a new CPI, derived against CT and validated using split sample testing, is a more accurate prognostic determinant in usual interstitial pneumonia than an individual pulmonary function test.
AB - In idiopathic pulmonary fibrosis, the quantitation of disease severity using pulmonary function tests is often confounded by emphysema. We have identified the composite physiologic index (CPI) most closely reflecting the morphologic extent of pulmonary fibrosis. Consecutive patients with a clinical/computed tomography (CT) diagnosis of idiopathic pulmonary fibrosis (n = 212) were divided into group I (n = 106) and group II (n = 106). The CPI was derived in group I (by fitting pulmonary function tests against disease extent on CT) and was tested in Group II. The formula for the CPI was as follows: extent of disease on CT = 91.0 - (0.65 × percent predicted diffusing capacity for carbon monoxide [DLCO]) - (0.53 × percent predicted FVC) + (0.34 × percent predicted FEV1). In group II, the CPI correlated more strongly with disease extent on CT (r2 = 0.51) than the individual pulmonary function test (DLCO the highest value, r2 = 0.38). A subanalysis demonstrated that the better fit of the CPI was ascribable to a correction of the confounding effects of emphysema. Mortality was predicted more accurately by the CPI than by a pulmonary function test in all clinical subgroups, including a separate cohort of 36 patients with histologically proven usual interstitial pneumonia (CPI, p < 0.0005; FVC, p = 0.002; Po2, p = 0.002). In conclusion, a new CPI, derived against CT and validated using split sample testing, is a more accurate prognostic determinant in usual interstitial pneumonia than an individual pulmonary function test.
KW - Composite physiologic index
KW - Idiopathic pulmonary fibrosis
KW - Prognosis
KW - Pulmonary function tests
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U2 - 10.1164/rccm.2111053
DO - 10.1164/rccm.2111053
M3 - Article
C2 - 12663338
AN - SCOPUS:0037383987
SN - 1073-449X
VL - 167
SP - 962
EP - 969
JO - American journal of respiratory and critical care medicine
JF - American journal of respiratory and critical care medicine
IS - 7
ER -