Table 1.
Baseline characteristics according to absence versus presence of self-reported urine output (UOP)
| Absence of UOP | Presence of UOP | Pa | |
|---|---|---|---|
| % (n) of patients | 25.4 (170) | 74.6 (500) | n/a |
| Age (yr), mean ± SD | 51.6 ± 14.6 | 55.6 ± 14.3 | 0.004 |
| Female, % (n) | 42.9 (73) | 44.2 (221) | 0.78 |
| Race, % (n) | 0.43 | ||
| White | 57.1 (97) | 55.0 (275) | |
| Black | 36.5 (62) | 32.8 (164) | |
| Asian | 5.3 (9) | 9.4 (47) | |
| Pacific Islander | 1.2 (2) | 2.2 (11) | |
| Alaskan/American Indian | 0.0 (0) | 0.2 (1) | |
| Other race | 0.0 (0) | 0.4 (2) | |
| Hispanic ethnicity, % (n) | 52.9 (90) | 46.8 (234) | 0.17 |
| Vintage (mo), mean ± SD | 87.0 ± 59.3 | 37.2 ± 36.3 | <0.001 |
| Vintage, % (n) | <0.001 | ||
| <1 yr | 2.4 (4) | 27.2 (135) | |
| 1 to <2 yr | 12.4 (21) | 20.9 (104) | |
| ≥2 yr | 85.2 (144) | 51.9 (258) | |
| Diabetes, % (n) | 48.8 (83) | 55.8 (279) | 0.11 |
| Vascular access, % (n) | 0.14 | ||
| AVF/AVG | 77.1 (131) | 70.6 (353) | |
| Catheter | 8.8 (15) | 14.6 (73) | |
| Unknown | 14.1 (24) | 14.8 (74) | |
| Laboratory tests, median (IQR) | |||
| Serum albumin (g/dl) | 4.1 (3.9, 4.3) | 4.0 (3.8, 4.2) | 0.15 |
| Alkaline phosphatase (IU/l) | 91 (74, 130) | 85 (65, 116) | 0.03 |
| Calcium (mg/dl) | 9.2 (8.7, 9.6) | 9.1 (8.7, 9.5) | 0.67 |
| Serum creatinine (mg/dl) | 10.6 (8.5, 12.7) | 9.3 (7.2, 11.4) | <0.001 |
| Ferritin (ng/ml) | 625 (405, 820) | 638 (395, 872) | 0.64 |
| Hemoglobin (g/dl) | 10.7 (10.1, 11.4) | 10.7 (10.1, 11.2) | 0.30 |
| Iron saturation (%) | 28 (22, 36) | 28 (22, 35) | 0.44 |
| nPCR (g/kg per day) | 1.0 (0.9, 1.2) | 1.0 (0.9, 1.2) | 0.18 |
| Phosphorus (mg/dl) | 5.1 (3.9, 6.1) | 4.9 (4.1, 5.9) | >0.99 |
| Potassium (mEq/l) | 5.1 (4.7, 5.4) | 4.8 (4.4, 5.2) | <0.001 |
| PTH (pg/ml) | 365 (226, 579) | 348 (218, 491) | 0.30 |
| Single pool Kt/V | 1.7 (1.5, 2.0) | 1.6 (1.4, 1.8) | <0.001 |
| Laboratory tests, % (n) | |||
| Potassium (mEq/l) | <0.001 | ||
| <3.5 | 0 (0) | 0 (0) | |
| 3.5–5.0 | 49.0 (77) | 65.6 (286) | |
| >5.0–5.5 | 29.9 (47) | 22.2 (97) | |
| >5.5 | 21.0 (33) | 12.2 (53) | |
| Body anthropometry, median (IQR) | |||
| BMI (kg/m2) | 26.6 (23.0, 30.2) | 26.5 (23.4, 31.7) | 0.78 |
AVF, arteriovenous fistula; AVG, arteriovenous graft; BMI, body mass index; nPCR, normalized protein catabolic rate; PTH, parathyroid hormone.
a
P values calculated by analysis of variance, χ2, or Kruskal-Wallis tests.