Table 1.
Patient Characteristics of the Overall Cohort, the Antibody-Mediated Rejection Group (AMR) by Presentationa, and the AMR-Free Matched Controlsb
| Non-AMR Patients (n=2,097) | P- Valuec | AMR Patients | P-Valued | Matched Controls (n=231) c | P-Valuee | |||
|---|---|---|---|---|---|---|---|---|
| Overall (n=219) | Subclinical AMR (n=77) | Clinical AMR (n=142) | ||||||
| Transplant Type | <0.001 | 0.027 | 0.69 | |||||
| Deceased Donor | ||||||||
| Compatible | 48.0% | 7.8% | 1.3% | 11.3% | 90.9% | |||
| HLA-Incompatible | 2.7% | 21.0% | 22.1% | 20.4% | 74.2% | |||
| Live Donor | ||||||||
| Compatible | 38.6% | 2.7% | 5.2% | 1.4% | 63.6% | |||
| ABO-Incompatible | 3.3% | 5.0% | 2.6% | 6.3% | 75.0% | |||
| HLA-Incompatible | 7.3% | 63.5% | 68.8% | 60.6% | 75.0% | |||
| Age at Transplant (SD) | 50.8 (14.2) | <0.001 | 45.8 (13.4) | 44.8 (12.2) | 46.3 (14.1) | 0.43 | 45.5 (10.8) | 0.67 |
| Female | 42.9% | <0.001 | 58.9% | 61.0% | 57.7% | 0.64 | 64.1% | 0.63 |
| African-American | 34.8% | 0.003 | 24.7% | 23.4% | 25.3% | 0.75 | 27.7% | 0.46 |
| Public Insurance | 45.2% | <0.001 | 65.7% | 64.9% | 66.2% | 0.74 | 49.3% | 0.018 |
| BMI (SD) | 27.5 (5.9) | <0.001 | 25.9 (6.1) | 26.0 (6.7) | 25.9 (5.7) | 0.95 | 26.3 (6.3) | 0.72 |
| Cause of ESRD | <0.001 | 0.36 | 0.68 | |||||
| Glomerular Diseases | 23.9% | 38.4% | 35.1% | 40.1% | 34.2% | |||
| Diabetes Mellitus | 18.6% | 9.6% | 6.5% | 11.3% | 10.0% | |||
| Hypertensive Nephrosclerosis | 31.1% | 18.3% | 15.6% | 19.7% | 15.6% | |||
| Polycystic Kidney Disease | 9.8% | 9.6% | 10.4% | 9.1% | 12.5% | |||
| Renovascular & Other Vascular Diseases | 0.7% | 3.2% | 3.9% | 2.8% | 1.3% | |||
| Other or Missing (includes Tubular and Congenital) | 15.8% | 21.0% | 28.6% | 16.9% | 26.4% | |||
| Peak PRA/CPR (IQR) | 2 (0–33) | <0.001 | 93 (68–100) | 93 (85–100) | 92 (64–100) | 0.16 | 94 (83–100) | 0.89 |
| Previous Transplant | 16.7% | <0.001 | 55.2% | 61.0% | 52.1% | 0.20 | 57.6% | 0.91 |
| Zero HLA-mismatch | 7.9% | <0.001 | 0.9% | 0.0% | 1.4% | 0.29 | 1.7% | 0.24 |
| Time on Dialysis Prior to Recent Transplant | <0.001 | 0.10 | 0.20 | |||||
| Preemptive | 17.9% | 5.9% | 9.1% | 4.2% | 7.8% | |||
| ≤2years | 31.9% | 14.2% | 13.0% | 14.8% | 16.4% | |||
| 2–6 years | 32.1% | 23.7% | 15.6% | 28.2% | 25.5% | |||
| ≥6 years | 18.1% | 56.2% | 62.3% | 52.8% | 50.2% | |||
| Donor Age (SD) | 40.7 (14.8) | 0.16 | 42.2 (12.9) | 43.8 (12.2) | 41.3 (13.2) | 0.16 | 38.7 | 0.007 |
AMR=antibody-mediated rejection, SD=standard deviation, BMI=body mass index, ESRD=end stage renal disease, IQR=interquartile range, PRA/CPRA=panel reactive antibody/calculated panel reactive antibody
- Clinical AMR was distinguished from subclinical AMR by the presence of evidence of graft dysfunction, manifested as oliguria/anuria, an increase in serum creatinine by ≥20% from baseline, treatment of cell-mediated rejection and/or thrombotic microangiopathy within the two prior weeks, the need for hemodialysis>7 days post-transplant, or new onset proteinuria at the time of the AMR-defining biopsy.
– AMR patients were matched in a 1:3 ratio on HLA-compatibility, ABO-compatibility, donor type (deceased versus live), previous transplant, peak PRA/CPRA, age, and year of transplant to AMR-free patients.
- Refers to the statistical test that tested the difference between AMR patients and non-AMR patients.
- Refers to the statistical test that tested the difference between patients with a subclinical AMR presentation and patients with a clinical AMR presentation.
- Refers to the statistical test that tested the difference between subclinical AMR patients and matched controls.