TY - JOUR
T1 - Idiopathic pulmonary fibrosis
T2 - Gender-age-physiology index stage for predicting future lung function decline
AU - Salisbury, Margaret L.
AU - Xia, Meng
AU - Zhou, Yueren
AU - Murray, Susan
AU - Tayob, Nabihah
AU - Brown, Kevin K.
AU - Wells, Athol U.
AU - Schmidt, Shelley L.
AU - Martinez, Fernando J.
AU - Flaherty, Kevin R.
N1 - Publisher Copyright:
Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
PY - 2016/2
Y1 - 2016/2
N2 - Background: Idiopathic pulmonary fibrosis is a progressive lung disease with variable course. The Gender-Age-Physiology (GAP) Index and staging system uses clinical variables to stage mortality risk. It is unknown whether clinical staging predicts future decline in pulmonary function. We assessed whether the GAP stage predicts future pulmonary function decline and whether interval pulmonary function change predicts mortality after accounting for stage. Methods: Patients with idiopathic pulmonary fibrosis (N = 657) were identified retrospectively at three tertiary referral centers, and baseline GAP stages were assessed. Mixed models were used to describe average trajectories of FVC and diffusing capacity of the lung for carbon monoxide (DLCO). Multivariable Cox proportional hazards models were used to assess whether declines in pulmonary function ≥ 10% in 6 months predict mortality after accounting for GAP stage. Results: Over a 2-year period, GAP stage was not associated with differences in yearly lung function decline. After accounting for stage, a 10% decrease in FVC or DLCO over 6 months independently predicted death or transplantation (FVC hazard ratio, 1.37; DLCO hazard ratio, 1.30; both, P ≤ .03). Patients with GAP stage 2 with declining pulmonary function experienced a survival profile similar to patients with GAP stage 3, with 1-year event-free survival of 59.3% (95% CI, 49.4-67.8) vs 56.9% (95% CI, 42.2-69.1). Conclusions: Baseline GAP stage predicted death or lung transplantation but not the rate of future pulmonary function decline. After accounting for GAP stage, a decline of ≥ 10% over 6 months independently predicted death or lung transplantation.
AB - Background: Idiopathic pulmonary fibrosis is a progressive lung disease with variable course. The Gender-Age-Physiology (GAP) Index and staging system uses clinical variables to stage mortality risk. It is unknown whether clinical staging predicts future decline in pulmonary function. We assessed whether the GAP stage predicts future pulmonary function decline and whether interval pulmonary function change predicts mortality after accounting for stage. Methods: Patients with idiopathic pulmonary fibrosis (N = 657) were identified retrospectively at three tertiary referral centers, and baseline GAP stages were assessed. Mixed models were used to describe average trajectories of FVC and diffusing capacity of the lung for carbon monoxide (DLCO). Multivariable Cox proportional hazards models were used to assess whether declines in pulmonary function ≥ 10% in 6 months predict mortality after accounting for GAP stage. Results: Over a 2-year period, GAP stage was not associated with differences in yearly lung function decline. After accounting for stage, a 10% decrease in FVC or DLCO over 6 months independently predicted death or transplantation (FVC hazard ratio, 1.37; DLCO hazard ratio, 1.30; both, P ≤ .03). Patients with GAP stage 2 with declining pulmonary function experienced a survival profile similar to patients with GAP stage 3, with 1-year event-free survival of 59.3% (95% CI, 49.4-67.8) vs 56.9% (95% CI, 42.2-69.1). Conclusions: Baseline GAP stage predicted death or lung transplantation but not the rate of future pulmonary function decline. After accounting for GAP stage, a decline of ≥ 10% over 6 months independently predicted death or lung transplantation.
KW - Idiopathic pulmonary fibrosis
KW - Interstitial lung disease
KW - Lung function
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U2 - 10.1378/chest.15-0530
DO - 10.1378/chest.15-0530
M3 - Article
C2 - 26425858
AN - SCOPUS:84958040637
SN - 0012-3692
VL - 149
SP - 491
EP - 498
JO - Chest
JF - Chest
IS - 2
ER -