Table 4.
Univariable and multivariable analyses of the associations with post-biopsy allograft failure in patients with recurrent IgAN
| Variable | Univariable (n = 80) |
Multivariable (n = 67), N events = 33* |
|||
|---|---|---|---|---|---|
| N events | HR (95% CI) | p value | HR (95% CI) | p value | |
| Recipient age at biopsy (per each year) | 33 | 1.01 (0.98–1.04) | 0.55 | ||
| Recipient, female gender | 33 | 0.71 (0.33–1.54) | 0.39 | ||
| Recipient, European ancestry1 | 33 | 0.79 (0.37–1.70) | 0.55 | ||
| Donor, European ancestry2 | 23 | 0.99 (0.36–2.75) | 0.99 | ||
| Allograft from living donor | 33 | 0.62 (0.31–1.25) | 0.18 | ||
| Induction with thymoglobulin3 | 30 | 1.16 (0.55–2.45) | 0.7 | ||
| Steroid-free regimens | 33 | 0.68 (0.31–1.47) | 0.33 | ||
| Post-transplant interval (per month) | 33 | 1.01 (1.01–1.01) | <0.001 | 1.01 (0.99–1.01) | 0.14 |
| Serum creatinine at biopsy (mg/dL)4 | 33 | 1.94 (1.40–2.69) | <0.001 | 2.81 (1.69–4.68) | <0.001 |
| Proteinuria (g/g vs. mg/dL)5 | 33 | 1.15 (1.07–1.24) | <0.001 | 1.20 (1.07–1.34) | 0.002 |
| Concurrent acute rejection | 33 | 3.21 (1.54–6.70) | 0.002 | 3.51 (1.11–11.0) | 0.03 |
| # Of HLA matches (per antigen: 0–6) | 33 | 0.82 (0.67–1.01) | 0.06 | 0.68 (0.50–0.91) | 0.009 |
| Protocol biopsy | 33 | 0.4 (0.05–2.49) | 0.3 | ||
| Mesangial score (M: 0–1)6 | 33 | 2.14 (1.05–4.34) | 0.04 | ||
| Endocapillary proliferation score (E: 0–1)6 | 33 | 1.50 (0.74–3.05) | 0.26 | ||
| Cellular or fibrocellular crescent score (C0–2)6 | 33 | 1.71 (0.73–3.98) | 0.22 | ||
| Segmental sclerosis score (S: 0–1)5 | 33 | 2.79 (1.32–5.93) | 0.007 | ||
| Tubular atrophy/interstitial fibrosis score (T: 0–2)6 | 33 | 2.56 (1.64–4.00) | <0.001 | ||
| Combined MEST-C score (0–7)5 | 33 | 1.51 (1.23–1.85) | <0.001 | 1.20 (0.86–1.66) | 0.28 |
DSA, donor-specific autoantibodies; IgAN, IgA nephropathy; HLA, human leukocyte antigen.
To avoid potential overfitting in multivariable analysis, we also used a forward and backward stepwise multivariable analysis that included variables with p < 0.1. Only the combined MEST-C score, rather than individual components were entered in multivariable analysis. Forward stepwise analyses showed that each of serum creatinine (3.09 [1.88–5.10], p < 0.001), proteinuria (1.26 [1.14–1.38], p < 0.001), concurrent acute rejection (6.67 [2.54–17.6], p < 0.001), and # HLA matches (0.73 [0.55–0.97], p = 0.03) were associated with inferior allograft survival.
Information on recipient ancestry was not available for 1 patient.
Information on donor ancestry was not available for 18 patients.
Information on induction therapy was not available for 11 patients.
Information on serum creatinine was not available for 4 patients.
Information on proteinuria was not available for 11 patients.
Histologic Oxford scores could not be assessed in 1 patient.