A score for estimating survival in idiopathic pulmonary fibrosis with rest SpO2>88.
BACKGROUND
Prediction models for survival at baseline evaluation have been proposed in IPF but some are difficult to use. The aim of present study was to develop a new mortality risk scoring system for patients with IPF at initial evaluation.


METHODS
One hundred twenty with definitive IPF were selected through a review of standardized medical records for interstitial lung diseases. Patients with resting SpO2<89% were excluded. Significant individual predictors we derived by a Cox proportional hazards model and transformed in categorical data according to cut-off points. Beta coefficients for each predictor were similar, so a score was created considering the sum of dichotomic (0 or 1) transformed variables.


RESULTS
Median follow-up time was 37.5 months. At the end of follow-up, 80 patients had died. Independent predictors of mortality by multivariate analysis included dyspnea (at rest or to light or moderate activities), FVC<70%,FEV1/FVC>0.89 and DLCO ≤ 40%. Resting SpO2 and ExSpO2 were excluded in final analysis. The hazard ratios ranged from 1.95 for dyspnoea to 2.30 for DLCO. When the total score was 0 (Stage I, n=28), median survival time was 68 months; when 1 or 2 (Stage II, n=69), it was 45 months; and when 3 or 4 (Stage III, n=23), it was 19 months (log rank= 60.44, p<0.001).


CONCLUSIONS
The score can separate IPF patients with high, intermediate and low survival.
Federal University of São Paulo. mrsoares2010@gmail.com.
Maria Raquel
MR
Soares
Carlos
C
Pereira
Rimarcs
R
Ferreira
Ester
E
Nei Aparecida Martins Coletta
Mariana
M
Silva Lima
Karin
K
Muller Storrer
D000367:Age Factors; D002423:Cause of Death; D015331:Cohort Studies; D016208:Databases, Factual; D018450:Disease Progression; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000000981:diagnostic imaging* / Q000401:mortality*; D053208:Kaplan-Meier Estimate; D008297:Male; D015999:Multivariate Analysis; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed / Q000379:methods; D014797:Vital Capacity
D010100:Oxygen