Figure 4. Kaplan-Meier survival curves of pneumonia-related septic shock patients, stratified by day-1 serum sex hormone levels.

Patients were categorized into two groups based on the optimal cut-off points of (A) progesterone and (B) estradiol from the ROC curves. Patients were categorized into four groups based on combining (C) progesterone and (D) estradiol optimal cut-off points and high or low Acute Physiology and Chronic Health Evaluation II (APACHE II) scores. Statistical significance was tested with the log-rank test.