Staging of acute exacerbation in patients with idiopathic pulmonary fibrosis.
BACKGROUND
The purpose of this study was to evaluate the predictors of a 3-month mortality rate of acute exacerbation of idiopathic pulmonary fibrosis (IPF) and provide a new staging system.


METHODS
A total of 594 patients with IPF were included in this retrospective, observational study conducted from January 2001 to December 2010 at Okinawa Chubu Hospital.


RESULTS
Among the 594 patients, 58 (9.8 %) developed acute exacerbation (AE) of IPF during the 10-year observation period. The median follow-up period for AE was 10.4 months. In-hospital mortality was 56.9 % and the 3-month mortality rate was 63.8 %. We identified the following four parameters in a multivariate analysis as: serum lactate dehydrogenase, sialylated carbohydrate antigen (KL-6), ratio of partial pressure of oxygen and fraction of inspiratory oxygen, and total extent of abnormal findings on high-resolution computed tomography of the chest. Patients were divided into two groups on the basis of the four composite parameters. Patients in the extensive disease-stage group required more mechanical ventilation and intensive therapy than those in the limited disease-stage group. The 3-month mortality rate was higher in patients in the extensive disease-stage group than in patients in the limited disease-stage group (80.6 vs. 54.5 %, respectively; p = 0.007).


CONCLUSIONS
Staging of AE in patients with IPF provided useful information regarding disease severity and short-term outcome.
Department of Respiratory Medicine, Okinawa Chubu Hospital, Okinawa, Japan, kishabatomoo@gmail.com.
Tomoo
T
Kishaba
Hitoshi
H
Tamaki
Yousuke
Y
Shimaoka
Hajime
H
Fukuyama
Shin
S
Yamashiro
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001944:Breath Tests; D016009:Chi-Square Distribution; D018450:Disease Progression; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000097:blood / Q000175:diagnosis* / Q000401:mortality* / Q000628:therapy; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007564:Japan; D053208:Kaplan-Meier Estimate; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood; D015999:Multivariate Analysis; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012121:Respiration, Artificial; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D007166:Immunosuppressive Agents; C060192:MUC1 protein, human; D018396:Mucin-1; D007770:L-Lactate Dehydrogenase; D010100:Oxygen