Figure 3
Survival curves according to serum heme oxygenase (HO)-1 level. The best cut-off value of serum HO-1 for predicting 12-week mortality was 41.8 ng/mL, determined by receiver-operating characteristic (ROC) analysis (area under the ROC curve for HO-1 0.71, sensitivity 74%, specificity 62%, P = 0.016). Log-rank test showed significant difference between the high and low serum HO-1 groups in the overall patients (P = 0.021) (A) and in patients with idiopathic pulmonary fibrosis (IPF) (P = 0.015) (B). There was similar tendency in patients with non-IPF (P = 0.347) (C).
