Table 1. Baseline characteristics of the overall study cohort and comparisons across ultrafiltration groupsa.
| Total (N=1846b) | ≤ 10 ml/h/kg (n=644b) | 10–13 ml/h/kg (n=517b) | > 13 ml/h/kg (n=685b) | Pc | |
|---|---|---|---|---|---|
| UFR (ml/h/kg) | 12.1 (4.6) | 7.7 (1.8) | 11.4 (8.6) | 16.8 (3.6) | — |
| Age (years) | 57.6 (14.0) | 60.4 (13.2) | 57.9 (13.5) | 54.8 (14.7) | < 0.001 |
| Female | 1038 (56.2%) | 367 (57.0%) | 272 (52.6%) | 399 (58.3%) | 0.13 |
| Black | 1156 (62.6%) | 405 (62.9%) | 324 (62.7%) | 427 (62.3%) | 0.98 |
| Smoking | 0.28 | ||||
| Never | 926 (50.2%) | 336 (52.3%) | 257 (49.8%) | 333 (48.7%) | — |
| Past | 597 (32.4%) | 205 (31.9%) | 176 (34.1%) | 216 (31.6%) | — |
| Current | 320 (17.4%) (N=1843) | 102 (15.9%) (n=643) | 83 (16.1%) (n=516) | 135 (19.7%) (n=684) | — |
| Vintage (years) | 0.12 | ||||
| < 1 | 490 (26.5%) | 180 (28.0%) | 135 (26.1%) | 175 (25.6%) | — |
| 1–2 | 382 (20.7%) | 147 (22.8%) | 109 (21.1%) | 126 (18.4%) | — |
| 2–4 | 434 (23.5%) | 136 (21.1%) | 134 (25.9%) | 164 (23.9%) | — |
| ≥ 4 | 540 (29.3%) | 181 (28.1%) | 139 (26.9%) | 220 (32.1%) | — |
| Access | 0.57 | ||||
| Graft | 1112 (60.2%) | 391 (60.7%) | 301 (58.2%) | 420 (61.3%) | — |
| Fistula | 612 (33.2%) | 205 (31.8%) | 184 (35.6%) | 223 (32.6%) | — |
| Catheter | 122 (6.6%) | 48 (7.5%) | 32 (6.2%) | 42 (6.1%) | — |
| Oliguricd | 1579 (86.3%) (N=1830) | 524 (82.0%) (n=639) | 444 (86.4%) (n=514) | 611 (90.3%) (n=677) | < 0.001 |
| SBP (mm Hg) | 0.001 | ||||
| < 120 | 99 (5.4%) | 41 (6.4%) | 28 (5.4%) | 30 (4.4%) | — |
| 120–140 | 438 (23.7%) | 162 (25.2%) | 140 (27.1%) | 136 (19.9%) | — |
| 140–160 | 667 (36.1%) | 247 (38.4%) | 181 (35.0%) | 239 (34.9%) | — |
| 160–180 | 490 (26.5%) | 148 (23.0%) | 136 (26.3%) | 206 (30.1%) | — |
| ≥ 180 | 152 (8.2%) | 46 (7.1%) | 32 (6.2%) | 74 (10.8%) | — |
| Diabetes | 823 (44.6%) | 290 (45.0%) | 242 (46.8%) | 291 (42.5%) | 0.32 |
| Congestive heart failure | 733 (39.7%) | 240 (37.3%) | 192 (37.1%) | 301 (43.9%) | 0.02 |
| Ischemic heart disease | 726 (39.3%) | 251 (39.0%) | 212 (41.0%) | 263 (38.4%) | 0.64 |
| Cerebrovascular disease | 360 (19.5%) | 142 (22.1%) | 104 (20.1%) | 114 (16.6%) | 0.04 |
| Peripheral vascular disease | 474 (25.7%) | 165 (25.6%) | 142 (27.5%) | 167 (24.4%) | 0.48 |
| Albumin (g/dl) | 3.6 (0.4) | 3.6 (0.3) | 3.6 (0.4) | 3.6 (0.4) | 0.63 |
| Creatinine (mg/dl) | 10.3 (2.9) (N=1845) | 10.0 (2.7) | 10.6 (2.9) | 10.3 (3.0) (n=684) | 0.005 |
| Hematocrit (%) | 0.001 | ||||
| < 30 | 334 (18.1%) | 84 (13.1%) | 96 (18.6%) | 154 (22.5%) | — |
| 30–33 | 438 (23.8%) | 153 (23.8%) | 115 (22.3%) | 170 (24.8%) | — |
| 33–36 | 545 (29.6%) | 209 (32.6%) | 159 (30.8%) | 177 (25.8%) | — |
| ≥ 36 | 526 (28.5%) (N=1843) | 196 (30.5%) (n=642) | 146 (28.3%) (n=516) | 184 (26.9%) | — |
| Phosphorous (mg/dl) | 5.8 (1.9) (N=1844) | 5.7 (1.8) (n=642) | 5.7 (1.7) | 6.0 (2.0) | 0.001 |
| ACEi/ARB use | 484 (26.2%) | 152 (23.6%) | 124 (24.0%) | 208 (30.4%) | 0.008 |
| α-1 blocker use | 125 (6.8%) | 51 (7.9%) | 33 (6.4%) | 41 (6.0%) | 0.34 |
| β-Blocker use | 553 (30.0%) | 180 (28.0%) | 151 (29.2%) | 222 (32.4%) | 0.19 |
| Calcium channel blocker use | 910 (49.3%) | 292 (45.3%) | 247 (47.8%) | 371 (54.2%) | 0.004 |
| Nitrate use | 317 (17.2%) | 112 (17.4%) | 81 (15.7%) | 124 (18.1%) | 0.53 |
| Other antihypertensive use | 416 (22.5%) | 127 (19.7%) | 121 (23.4%) | 168 (24.5%) | 0.10 |
| IDWG (kg) | 2.9 (1.1) | 2.1 (0.9) | 3.0 (0.9) | 3.6 (1.0) | < 0.001 |
| Session length (min) | 218 (24) | 226 (21) | 220 (23) | 209 (23) | < 0.001 |
| BMI (kg/m2) | < 0.001 | ||||
| < 18.5 | 125 (6.8%) | 20 (3.1%) | 21 (4.1%) | 84 (12.3%) | — |
| 18.5–24.9 | 896 (48.8%) | 233 (36.4%) | 230 (44.8%) | 433 (63.5%) | — |
| 25–29.9 | 519 (28.3%) | 227 (35.4%) | 165 (32.1%) | 127 (18.6%) | — |
| ≥ 30 | 297 (16.2%) (n=1837) | 161 (25.1%) (n=641) | 98 (19.1%) (n=514) | 38 (5.6%) (n=684) | — |
| High Kt/V group | 920 (49.8%) | 323 (50.2%) | 248 (48.0%) | 349 (51.0%) | 0.58 |
| High flux group | 921 (49.9%) | 329 (51.1%) | 246 (47.6%) | 346 (50.5%) | 0.46 |
Abbreviations: ACEi/ARB, angiotensin-converting enzyme inhibitor and/or angiotensin receptor blocker; BMI, body mass index; IDWG, interdialytic weight gain; SBP, systolic blood pressure; UFR, ultrafiltration rate.
a
Values presented as mean (s.d.) or n (%).
b
Except where noted.
c
Across UFR groups, determined by analysis of variance for continuous variables and χ2-testing for categorical variables.
d
Urine output ≤ 200 ml/day.