Table 1.
Characteristics of patients treated with intravenous versus subcutaneous epoetin
| Demographic and Clinical Variables of Study Patients | Route of Administration | |||
|---|---|---|---|---|
| Total (n=62,710) | Intravenous (n=57,602) | Subcutaneous (n=5108) | P Value | |
| Men (%) | 52.4 | 52.2 | 54.7 | <0.001 |
| Black (%) | 37.1 | 37.6 | 30.9 | <0.001 |
| Hispanic (%) | 12.6 | 12.6 | 12.6 | 0.97 |
| Age, yr | ||||
| Mean (SD) | 61.4 (15.3) | 61.3 (15.3) | 62.0 (15.2) | 0.004 |
| Median (interquartile range) | 63.3 (50.7–73.3) | 63.2 (50.7–73.3) | 64.1 (51.9–73.8) | |
| <65 yr old (%) | 46.0 | 45.8 | 47.9 | 0.004 |
| DM as the cause of ESRDa (%) | 42.2 | 42.0 | 44.7 | <0.001 |
| History of CHF, AMI, or stroke (%) | 25.9 | 26.1 | 23.7 | <0.001 |
| Dialysis vintage, yr (%) | ||||
| <0.5 | 12.2 | 12.0 | 14.4 | <0.001 |
| 0.5–0.9 | 14.2 | 14.1 | 15.2 | |
| 1.0–1.9 | 20.5 | 20.4 | 21.5 | |
| ≥2.0 | 53.1 | 53.4 | 48.9 | |
| Postdialysis BMI, kga | ||||
| Mean (SD) | 26.5 (7.00) | 26.5 (7.0) | 26.7 (6.8) | 0.07 |
| Median (interquartile range) | 25.2 (21.9–29.7) | 25.4 (21.9–29.7) | 25.4 (22.1–29.8) | |
| ≥25 (%) | 51.5 | 51.4 | 52.6 | 0.09 |
| Hgb | ||||
| Mean (SD) | 11.45 (1.23) | 11.45 (1.23) | 11.37 (1.22) | <0.001 |
| Median (interquartile range) | 11.53 (10.7–12.2) | 11.53 (10.8–12.2) | 11.47 (10.6–12.1) | |
| ≤11.5 (%) | 49.7 | 49.5 | 51.6 | 0.004 |
| TSAT<20a (%) | 23.6 | 23.4 | 26.2 | <0.001 |
| Serum ferritin <100 ng/ml (%) | 11.6 | 11.5 | 13.0 | 0.002 |
| Iron deficienta,b (%) | 5.2 | 5.1 | 6.8 | <0.001 |
| Prescribed intravenous irona (%) | 63.5 | 63.5 | 63.6 | 0.95 |
| Serum albumina ≥3.5/3.8 g/dlc (%) | 75.6 | 76.2 | 67.9 | <0.001 |
| Epoetin dose, units/kg per week | ||||
| Mean (SD) | 223 (158) | 227 (159) | 182 (133) | <0.001 |
| Median (interquartile range) | 183 (101–308) | 187 (103–314) | 146 (82–245) | <0.001 |
| <150 (%) | 40.7 | 39.8 | 51.0 | <0.001 |
| 150–299 (%) | 33.0 | 33.1 | 32.2 | |
| ≥300 (%) | 26.3 | 27.1 | 16.7 | |
| Facility (%) | ||||
| Nonprofit | 25.0 | 23.4 | 42.7 | <0.001 |
| Hospital based | 16.0 | 14.8 | 29.6 | <0.001 |
| Chain affiliated | 61.2 | 63.4 | 36.5 | <0.001 |
| <20 stations | 49.9 | 49.8 | 51.3 | 0.04 |
Continuous variables (with the exception of age and dialysis vintage) represent the mean of measurements recorded during 3-month study periods. DM, diabetes mellitus; CHF, congestive heart failure; AMI, acute myocardial infarction; BMI, body mass index; Hgb, hemoglobin; TSAT, transferrin saturation.
Numbers of patients for whom data were available (all, intravenous, and subcutaneous): DM as the cause of ESRD (62,698, 57,591, and 5107), BMI (61,994, 56,995, and 4999), TSAT (59,082, 54,442, and 4640), serum ferritin (59,890, 55,105, and 4785), iron deficient (57,489, 52,979, and 4510), prescribed iron (62,494, 57,404, and 5090), and serum albumin (62,394, 57,324, and 5070).
Mean TSAT <20% and mean serum ferritin <100 ng/ml.
Bromcresol green/bromcresol purple laboratory methods.