Fig. 2

Kaplan-Meier curves for all-cause mortality stratified by admission BUN quartiles. (a) 30-day mortality, (b) 90-day mortality, (c) 180-day mortality. Q1: BUN ≤ 14 mg/dL; Q2: 14 < BUN ≤ 19 mg/dL; Q3: 19 < BUN ≤ 27 mg/dL; Q4: BUN > 27 mg/dL. The number of patients at risk at each time point for each quartile (Q1: n = 941; Q2: n = 814; Q3: n = 741; Q4: n = 754) is shown below the graph. The log-rank test was used to compare overall survival differences, with a P value < 0.0001 for all panels.