Table 1. Clinical Characteristics According to Clusters of Black Kidney Transplant Recipients.
| Characteristic | Recipient groupa | P value | ||||
|---|---|---|---|---|---|---|
| All (N = 22 687) | Cluster 1 (n = 3196) | Cluster 2 (n = 3096) | Cluster 3 (n = 7678) | Cluster 4 (n = 8717) | ||
| Recipient age, mean (SD), y | 51.4 (12.6) | 48.5 (11.8) | 48.4 (13.0) | 44.4 (11.3) | 59.6 (8.7) | <.001 |
| Recipient sex | ||||||
| Men | 13 635 (60) | 1410 (44) | 1807 (58) | 4961 (65) | 5457 (63) | <.001 |
| Women | 9052 (40) | 1786 (56) | 1289 (42) | 2717 (35) | 3260 (37) | |
| ABO blood group | ||||||
| A | 6452 (28) | 861 (27) | 899 (29) | 2165 (28) | 2527 (29) | <.001 |
| B | 4334 (19) | 539 (17) | 723 (23) | 1410 (18) | 1662 (19) | |
| AB | 1255 (5) | 141 (4) | 169 (5) | 445 (6) | 500 (6) | |
| O | 10 646 (47) | 1655 (52) | 1305 (42) | 3658 (48) | 4028 (46) | |
| BMI, mean (SD) | 29.3 (5.7) | 28.0 (5.6) | 29.3 (5.7) | 28.6 (5.8) | 30.5 (5.3) | <.001 |
| Kidney retransplant | 2413 (11) | 2178 (68) | 112 (4) | 58 (1) | 65 (1) | <.001 |
| Kidney donor status | ||||||
| Non-ECD deceased | 17 052 (75) | 2919 (91) | 151 (5) | 7580 (99) | 6402 (73) | <.001 |
| ECD deceased | 2482 (11) | 172 (5) | 32 (1) | 39 (1) | 2239 (26) | |
| Living | 3153 (14) | 105 (3) | 2913 (94) | 59 (1) | 76 (1) | |
| Dialysis duration | ||||||
| Preemptive | 1798 (8) | 264 (8) | 768 (25) | 397 (5) | 369 (4) | <.001 |
| <1 y | 1787 (8) | 215 (7) | 666 (22) | 404 (5) | 502 (6) | |
| 1-3 y | 4069 (18) | 745 (23) | 977 (32) | 1080 (14) | 1267 (15) | |
| >3 y | 15 033 (66) | 1972 (62) | 685 (22) | 5797 (76) | 6579 (75) | |
| Cause of ESKD | ||||||
| Diabetes | 6460 (28) | 359 (11) | 860 (28) | 464 (6) | 4777 (55) | <.001 |
| Hypertension | 8189 (36) | 650 (20) | 924 (30) | 4107 (53) | 2508 (29) | |
| Glomerular disease | 4027 (18) | 598 (19) | 800 (26) | 1974 (26) | 655 (7) | |
| PKD | 839 (4) | 89 (3) | 175 (6) | 293 (4) | 282 (3) | |
| Other | 3172 (14) | 1500 (47) | 337 (11) | 840 (11) | 495 (6) | |
| Comorbidity | ||||||
| Diabetes | 8253 (36) | 770 (24) | 1055 (34) | 751 (10) | 5677 (65) | <.001 |
| Malignant neoplasm | 1580 (7) | 218 (7) | 169 (5) | 386 (5) | 887 (10) | <.001 |
| Peripheral vascular disease | 2119 (9) | 216 (7) | 228 (7) | 388 (5) | 1287 (15) | <.001 |
| PRA, median (IQR), % | 0 (0-48) | 99 (87-100) | 0 (0-9) | 0 (0-18) | 0 (0-17) | <.001 |
| Positive HCV serostatus | 1825 (8) | 238 (7) | 95 (3) | 546 (7) | 946 (11) | <.001 |
| Positive HBs antigen | 340 (1) | 41 (1) | 42 (1) | 139 (2) | 118 (1) | .052 |
| Positive HIV serostatus | 767 (3) | 43 (1) | 66 (2) | 437 (6) | 221 (3) | <.001 |
| Functional status, % | ||||||
| 10-30 | 50 (0.2) | 6 (0.2) | 9 (<1) | 11 (<1) | 24 (<1) | <.001 |
| 40-70 | 11 869 (52) | 1660 (52) | 1258 (41) | 3810 (50) | 5141 (59) | |
| 80-100 | 10 768 (47) | 1530 (48) | 1829 (59) | 3587 (50) | 3552 (41) | |
| Working income | 5883 (26) | 914 (29) | 1428 (46) | 2161 (28) | 1380 (16) | <.001 |
| Public insurance | 18 504 (81) | 2591 (81) | 1658 (53) | 6632 (86) | 7623 (87) | <.001 |
| US resident | 22 597 (>99) | 3187 (>99) | 3075 (99) | 7644 (>99) | 8691 (>99) | .02 |
| ≥Undergraduate educational attainment | 12 405 (55) | 1897 (59) | 2108 (68) | 3855 (50) | 4545 (52) | <.001 |
| Serum albumin level, mean (SD), g/dL | 4.0 (0.6) | 3.8 (0.6) | 3.9 (0.5) | 4.1 (0.5) | 3.9 (0.5) | <.001 |
| Donor age, mean (SD), y | 38.4 (14.8) | 34.8 (13.8) | 40.9 (12.0) | 28.4 (12.4) | 47.2 (11.9) | <.001 |
| Donor sex | ||||||
| Men | 13 064 (58) | 2010 (63) | 1103 (36) | 5102 (66) | 4849 (56) | <.001 |
| Women | 9623 (42) | 1186 (37) | 1993 (64) | 2576 (33) | 3823 (44) | |
| Donor race | ||||||
| Black | 5918 (26) | 909 (28) | 2005 (65) | 1458 (19) | 1546 (18) | <.001 |
| Hispanic | 2266 (10) | 421 (13) | 140 (5) | 873 (11) | 832 (9) | <.001 |
| White | 13 784 (61) | 1765 (55) | 844 (27) | 5150 (67) | 6025 (69) | <.001 |
| Otherb | 719 (3) | 101 (3) | 107 (3) | 197 (3) | 314 (4) | .002 |
| History of hypertension in donor | 5477 (24) | 654 (20) | 137 (4) | 780 (10) | 3906 (45) | <.001 |
| KDPI | ||||||
| Living donor | 3153 (14) | 105 (3) | 2913 (94) | 59 (1) | 76 (1) | <.001 |
| <85% | 17 892 (79) | 3028 (95) | 163 (5) | 7563 (99) | 7228 (83) | |
| ≥85% | 1552 (7) | 63 (2) | 20 (1) | 56 (1) | 1413 (16) | |
| HLA antigen mismatch, median (IQR) | ||||||
| A | 2 (1-2) | 1 (1-2) | 1 (1-2) | 2 (1-2) | 2 (1-2) | <.001 |
| B | 2 (1-2) | 1 (1-2) | 1 (1-2) | 2 (2-2) | 2 (2-2) | <.001 |
| DR | 1 (1-2) | 1 (0-1) | 1 (1-2) | 1 (1-2) | 1 (1-2) | <.001 |
| ABDR | 5 (4-5) | 4 (3-4) | 4 (3-5) | 5 (4-5) | 5 (4-5) | <.001 |
| Cold ischemia time, mean (SD), h | 15.8 (9.8) | 18.7 (8.4) | 2.4 (3.3) | 16.1 (8.0) | 19.3 (9.1) | <.001 |
| Kidney on pump | 9496 (42) | 1115 (35) | 17 (1) | 3216 (42) | 5148 (59) | <.001 |
| Delay graft function | 6720 (30) | 972 (30) | 123 (4) | 1998 (26) | 3627 (42) | <.001 |
| Allocation type | ||||||
| Local | 16 718 (74) | 1283 (40) | 3079 (99) | 6310 (82) | 6046 (69) | <.001 |
| Regional | 2821 (12) | 623 (19) | 8 (<1) | 652 (8) | 1538 (18) | |
| National | 3148 (14) | 1290 (40) | 9 (<1) | 716 (9) | 1133 (13) | |
| EBV risk status | ||||||
| Low | 122 (1) | 22 (1) | 35 (1) | 53 (1) | 12 (<1) | <.001 |
| Moderate | 21 200 (93) | 2970 (93) | 2888 (93) | 7101 (92) | 8241 (95) | |
| High | 1365 (6) | 204 (6) | 173 (5) | 524 (7) | 464 (5) | |
| CMV status | ||||||
| Donor negative/recipient negative | 2531 (11) | 261 (8) | 458 (15) | 1031 (13) | 781 (9) | <.001 |
| Donor negative/recipient positive | 6554 (29) | 1002 (31) | 794 (26) | 2385 (31) | 2373 (27) | |
| Donor positive/recipient positive | 10 398 (46) | 1569 (49) | 1362 (44) | 3017 (39) | 4450 (51) | |
| Donor positive/recipient negative | 3204 (14) | 364 (11) | 482 (15) | 1245 (16) | 1113 (13) | |
| Induction immunosuppression | ||||||
| Thymoglobulin | 14 376 (63) | 2303 (72) | 1711 (55) | 4879 (63) | 5483 (63) | <.001 |
| Alemtuzumab | 3792 (17) | 465 (15) | 662 (21) | 1305 (17) | 1360 (16) | <.001 |
| Basiliximab | 3684 (16) | 243 (8) | 607 (20) | 1176 (15) | 1658 (19) | <.001 |
| Other | 328 (1) | 46 (1) | 55 (2) | 101 (1) | 126 (1) | .35 |
| None | 1547 (7) | 222 (7) | 186 (6) | 557 (7) | 582 (7) | .12 |
| Maintenance immunosuppression | ||||||
| Tacrolimus | 20 689 (91) | 2942 (92) | 2824 (91) | 7050 (92) | 7873 (90) | .002 |
| Cyclosporine | 184 (1) | 26 (1) | 35 (1) | 51 (1) | 72 (1) | .11 |
| Mycophenolate | 20 907 (92) | 2952 (92) | 2857 (92) | 7139 (93) | 7959 (91) | .001 |
| Azathioprine | 65 (<1) | 5 (<1) | 13 (<1) | 22 (<1) | 25 (<1) | .28 |
| mTOR inhibitors | 62 (<1) | 17 (1) | 11 (<1) | 19 (<1) | 115 (1) | .01 |
| Corticosteroid | 16 131 (71) | 2598 (81) | 1947 (63) | 5579 (73) | 6007 (69) | <.001 |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by square of height in meters); CMV, cytomegalovirus; EBV, Epstein-Barr virus; ECD, extended criteria donor; ESKD, end-stage kidney disease; HBs, hepatitis B surface; HCV, hepatitis C virus; HLA, human leukocyte antigen; KDPI, kidney donor profile index; mTOR, mammalian target of rapamycin; PKD, polycystic kidney disease; PRA, panel reactive antibody.
SI conversion factor: To convert serum albumin to g/L, multiply by 10.
a
Unless otherwise indicated, data are expressed as number (percentage) of recipients. Percentages have been rounded and may not total 100.
b
Includes Asian, American Indian, Alaska Native, Native Hawaiian, or other Pacific Islander.