Table 3.
Cox proportional hazards models exploring the relationship between serum iron levels and 28-day mortality
| Factors | Univariate model | Multivariate model | ||
|---|---|---|---|---|
| HR (95% CI) | P Value | HR (95% CI) | P Value | |
| Sex (M) | 1.436 (1.037–1.990) | 0.029 | 1.208 (0.760–5.971) | 0.263 |
| Age (years) | ||||
| 16–59 | Reference | – | Reference | – |
| ≥ 60 | 1.217 (0.871–1.699) | 0.250 | 1.720 (0.868–1.680) | 0.004 |
| Congestive heart failure | 0.823 (0.591–1.146) | 0.248 | 0.913 (0.633–1.316) | 0.624 |
| Hypertension | 0.759 (0.550–1.047) | 0.093 | 0.717 (0.510–1.010) | 0.057 |
| SOFA score | ||||
| < 2 | Reference | – | Reference | – |
| ≥ 2 | 3.653 (1.353–9.866) | 0.011 | 2.130 (0.760–5.971) | 0.151 |
| Stage of AKI | ||||
| Stage 1 | Reference | – | Reference | – |
| Stage 2 | 1.231 (0.709–2.136) | 0.461 | 1.152 (0.661–2.006) | 0.618 |
| Stage 3 | 2.131 (1.353–3.356) | 0.001 | 1.543 (0.919–2.589) | 0.101 |
| Treatment | ||||
| Non-RRT | Reference | – | Reference | – |
| RRT | 1.663 (1.186–2.334) | 0.003 | 1.008 (0.653–1.556) | 0.972 |
| Creatinine | 1.104 (1.005–1.213) | 0.040 | 0.992 (0.882–1.116) | 0.893 |
| Transferrin | 0.993 (0.990–0.996) | < 0.001 | 0.996 (0.993–0.999) | 0.021 |
| Ferritin | 1.001 (1.001–1.001) | < 0.001 | 1.001 (1.000–1.001) | 0.029 |
| Iron group | ||||
| Low iron group | Reference | – | – | |
| High iron group | 1.868 (1.354–2.576) | < 0.001 | 1.832 (1.305–2.573) | < 0.001 |
HR Hazard Ratio, CI Confidence Interval, SOFA Sequential Organ Failure Assessment, AKI Acute Kidney Injury, RRT Renal Replacement Therapy