Significance of lung shrinkage on CXR as a prognostic factor in patients with idiopathic pulmonary fibrosis.
OBJECTIVE
The aim of this study was to determine whether the presence of lung shrinkage on CXR can predict diminished survival in patients with idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP).


METHODS
In a hospital-based cohort study 68 subjects diagnosed with IPF/UIP by surgical lung biopsy or at autopsy were observed for a mean of 7.6 years. The radiographic scores from Cherniack's method, pulmonary function tests, arterial blood gas, and haematological data were obtained at initial presentation. Longitudinal radiographic changes over a mean interval of 2.7 years were measured. Survival analysis was performed using Kaplan-Meier and Cox's proportional hazards regression analysis.


RESULTS
At some point during the observation period 36 (53%) of 68 patients did not exhibit lung shrinkage and 32 (47%) of 68 patients showed lung shrinkage. Patients with lung shrinkage were more likely to have a diminished survival than those with lung preservation; median survival was 4.4 vs 7.8 years, respectively. Lung shrinkage during the observation period (hazard ratio, 3.89; 95% CI = 1.68-9.01; P= 0.001) was associated with lower rates of survival.


CONCLUSIONS
In patients with IPF/UIP, lung shrinkage on CXR during the observation period was a poor prognostic factor.
Kawabata
Hidenobu
H
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Nagai
Sonoko
S
Hayashi
Michio
M
Nakamura
Hiroshi
H
Nagao
Taisi
T
Shigematsu
Michio
M
Kitaichi
Masanori
M
Izumi
Takateru
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011379:Prognosis; D011658:Pulmonary Fibrosis / Q000097:blood / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D011859:Radiography; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D016019:Survival Analysis