Table 4.
Cox proportional hazards models exploring the relationship between serum iron levels and 90-day mortality
| Factors | Univariate model | Multivariate model | ||
|---|---|---|---|---|
| HR (95% CI) | P Value | HR (95% CI) | P Value | |
| Sex (M) | 1.524 (1.142–2.034) | 0.004 | 1.308 (0.976–1.753) | 0.072 |
| Age (years) | ||||
| 16–59 | Reference | – | Reference | – |
| ≥ 60 | 1.44 (1.065–1.947) | 0.018 | 1.910 (1.372–2.661) | < 0.001 |
| Congestive heart failure | 1.012 (0.759–1.348) | 0.936 | 1.115 (0.812–1.531) | 0.502 |
| Hypertension | 0.7821 (0.589–1.039) | 0.090 | 0.703 (0.520–0.951) | 0.022 |
| SOFA score | ||||
| < 2 | Reference | – | Reference | – |
| ≥ 2 | 2.760 (1.297–5.872) | 0.008 | 1.534 (0.694–3.387) | 0.290 |
| Stage of AKI | ||||
| Stage 1 | Reference | – | Reference | – |
| Stage 2 | 1.119 (0.693–1.807) | 0.647 | 1.102 (0.680–1.786) | 0.693 |
| Stage 3 | 2.030 (1.376–2.995) | < 0.001 | 1.587 (1.017–2.477) | 0.042 |
| Treatment | ||||
| Non-RRT | Reference | – | Reference | – |
| RRT | 1.505 (1.108–2.043) | 0.009 | 0.816 (0.553–1.203) | 0.304 |
| Creatinine | 1.112 (1.023–1.208) | 0.0127 | 1.030 (0.928–1.143) | 0.577 |
| Transferrin | 0.992 (0.989–0.995) | < 0.001 | 0.994 (0.991–0.997) | < 0.001 |
| Ferritin | 1.001 (1.001–1.001) | < 0.001 | 1.000 (1.000–1.001) | 0.086 |
| Iron group | ||||
| Low iron group | Reference | – | Reference | – |
| High iron group | 1.585 (1.190–2.112) | 0.002 | 1.741 (1.285–2.358) | < 0.001 |
HR Hazard Ratio, CI Confidence Interval, SOFA Sequential Organ Failure Assessment; AKI Acute Kidney Injury, RRT Renal Replacement Therapy