Table 2.
Patient characteristics according to 1-month intravenous iron dose
| Patient Characteristics | Total Cohort | Intravenous Iron Dose (mg) | P Valuea | |||
|---|---|---|---|---|---|---|
| None | >0–150 | >150–350 | >350 | |||
| n | 14,078 | 4193 | 1784 | 3114 | 4903 | |
| Demographics | ||||||
| Age, yr (median) | 64.0 | 64.0 | 63.0 | 64.0 | 63.0 | 0.47 |
| Sex (%) | 0.88 | |||||
| Women | 44.9 | 45.4 | 44.5 | 44.6 | 44.9 | |
| Race (%) | 0.47 | |||||
| White | 60.2 | 59.3 | 59.2 | 60.4 | 61.1 | |
| Black | 35.6 | 36.2 | 36.2 | 35.1 | 35.0 | |
| Other | 4.3 | 4.4 | 4.6 | 4.5 | 3.9 | |
| Ethnicity (%) | <0.01 | |||||
| Hispanic | 5.6 | 6.5 | 5.1 | 4.7 | 5.4 | |
| Non-Hispanic | 94.5 | 93.5 | 94.9 | 95.3 | 94.6 | |
| Cause of ESRD (%) | <0.001 | |||||
| Diabetes | 47.7 | 46.1 | 44.8 | 48.7 | 49.5 | |
| Hypertension | 27.7 | 26.7 | 29.2 | 28.9 | 27.3 | |
| GN | 9.1 | 9.6 | 9.6 | 9.3 | 8.3 | |
| Other | 15.5 | 17.7 | 16.4 | 13.1 | 14.8 | |
| Baseline comorbidities | ||||||
| Indexb | 4.0 (1.0–6.0) | 4.0 (1.0–6.0) | 3.0 (1.0–6.0) | 3.0 (1.0–6.0) | 4.0 (1.0–7.0) | 0.11 |
| Congestive heart failure (%) | 40.5 | 40.8 | 38.2 | 39.5 | 41.9 | 0.03 |
| Diabetes (%) | 61.4 | 58.8 | 58.9 | 63.1 | 63.4 | <0.001 |
| Hemoglobinopathyc (%) | 3.6 | 4.8 | 2.6 | 3.2 | 3.1 | <0.001 |
| Ferritin (ng/ml) and TSat (%) combination | <0.001 | |||||
| Ferritin≤500 and TSat≤20 | 46.7 | 33.1 | 37.4 | 44.4 | 62.9 | |
| Ferritin≤500 and TSat=21–30 | 20.8 | 19.2 | 21.8 | 25.8 | 18.4 | |
| Ferritin=501–800 and TSat≤20 | 5.7 | 4.3 | 7.1 | 6.5 | 5.9 | |
| Ferritin>800 regardless of TSat | 8.6 | 21.0 | 6.2 | 3.0 | 2.7 | |
| Other | 18.2 | 22.4 | 27.5 | 20.2 | 10.1 | |
| Ferritin<500 ng/ml and TSat>30% | 8.7 | 11.3 | 11.9 | 9.4 | 4.8 | |
| Ferritin>501–800 ng/ml and TSat=20% | 9.5 | 11.1 | 15.6 | 10.8 | 5.3 | |
| Hemoglobin, g/dl (%) | <0.001 | |||||
| ≤10 | 7.8 | 9.4 | 6.3 | 6.1 | 8.6 | |
| 10.1–11 | 11.3 | 12.4 | 10.0 | 8.9 | 12.3 | |
| 11.1–12 | 24.1 | 23.2 | 22.8 | 24.5 | 25.0 | |
| >12 | 56.7 | 54.9 | 61.0 | 60.6 | 54.1 | |
| Mean weekly epogen dose, units/wk (%) | <0.001 | |||||
| ≤5000 | 18.3 | 24.7 | 24.7 | 18.8 | 10.4 | |
| 5001–12,000 | 18.7 | 19.9 | 22.5 | 20.1 | 15.3 | |
| 12,001–25,000 | 30.2 | 27.9 | 27.7 | 31.1 | 32.5 | |
| >25,000 | 32.8 | 27.5 | 25.1 | 30.0 | 41.8 | |
| Vascular access (%) | <0.01 | |||||
| Arteriovenous fistula | 17.7 | 16.1 | 17.9 | 18.5 | 18.4 | |
| Arteriovenous graft | 9.4 | 10.3 | 8.5 | 9.8 | 8.7 | |
| Central venous catheter | 72.9 | 73.6 | 73.6 | 71.6 | 72.9 | |
| Serum albumin (g/dl)b | 3.6 (3.3–3.9) | 3.6 (3.3–3.9) | 3.6 (3.3–3.9) | 3.6 (3.3–3.9) | 3.6 (3.3–3.9) | 0.04 |
| Serum creatinine (g/dl)b | 6.1 (4.6–8.1) | 6.1 (4.6–8.1) | 6.2 (4.5–8.2) | 6.1 (4.6–8.0) | 6.1 (4.6–8.1) | 0.72 |
| Body mass index (kg/m2)b | 27.2 (23.1–32.6) | 26.6 (22.8–31.7) | 26.6 (22.8–32.0) | 27.2 (23.4–32.7) | 27.9 (23.5–33.5) | <0.001 |
| Infection in past 21 d (%) | 19.1 | 20.2 | 19.0 | 18.8 | 18.3 | 0.14 |
| Noninfection-related hospitalization in past 21 d (%) | 6.5 | 7.0 | 6.1 | 6.3 | 6.5 | 0.52 |
| Iron (mg) over the past 3 mob | 1000 (300–1600) | 0 (0–150) | 1100 (500–1500) | 1200 (650–1600) | 1250 (800–1700) | <0.001 |
TSat, saturation of transferrin.
a
Comparison across subgroups of 1-month cumulative intravenous iron dose.
b
Median and interquartile range.
c
Includes sickle cell, hereditary spherocytosis, myelodysplasia, multiple myeloma, and other anemia not caused by erythropoietin or iron deficiency; mean serum albumin findings are rounded. Values were 3.55, 3.55, 3.58, and 3.57 for intravenous iron doses of none, >0–150 mg, >150–350 mg, and >350 mg, respectively.