Table 4.
Mixed linear model to evaluate the impact of the function of the donated kidney on recipient eGFR
| Parameters | Reduced modela | Multivariable modelb | ||
|---|---|---|---|---|
| Estimate (95% CI) | P value | Estimate (95% CI) | P value | |
| Impact on recipient baseline eGFR, mL/min/1.73 m2 | ||||
| eGFR-dkc, per mL/min/1.73 m2 | Changes with each calculation | 0.6 (0.1 to 1.1) | 0.02 | |
| Recipient variables | ||||
| Age, per year | −0.2 (−0.5 to 0) | 0.06 | −0.2 (−0.4 to 0.1) | 0.23 |
| Female sex, yes vs. no | 3.5 (−4.7 to 11.7) | 0.40 | – | – |
| Preemptive transplantation, yes vs. no | 1.9 (−6.4 to 10.3) | 0.65 | – | – |
| Recipient of a re-transplant, yes vs. no | 4.7 (−8 to 17.3) | 0.46 | – | – |
| ABO/HLA incompatible transplantation, yes vs. no | 1.3 (−11.2 to 13.9) | 0.83 | – | - |
| Sum of HLA mismatch in A, B and DR, per n | −0.9 (−3.5 to 1.8) | 0.52 | – | – |
| IL-2R antibody induction, yes vs. no | −7.5 (−20.5 to 5.5) | 0.26 | – | – |
| Tacrolimus-based immunosuppression, yes vs. no | 2.6 (−7.5 to 12.6) | 0.61 | – | – |
| Belatacept-based immunosuppression, yes vs. no | −0.3 (−15.8 to 15.3) | 0.97 | – | – |
| LD variables | ||||
| Age, per year | −0.5 (−0.9 to 0) | 0.04 | −0.4 (−0.9 to 0) | 0.08 |
| Female sex, yes vs. no | −6.4 (−14.5 to 1.8) | 0.12 | −3.8 (−12.0 to 4.3) | 0.35 |
| BMI, per kg/m2 | 0.8 (−0.2 to 1.8) | 0.133 | 0.6 (−0.4–1.6) | 0.24 |
| Living-related, yes vs. no | −2.5 (−10.3 to 5.4) | 0.53 | – | – |
| Abnormal MTT of donated kidneyd, yes vs. no | −6.8 (−14.4 to 0.9) | 0.08 | −6.2 (−13.5 to 1.2) | 0.10 |
| Biopsy-proven rejection | ||||
| TCMR, yes vs. no | 0.1 (−9.5 to 9.7) | 0.99 | −2.0 (−11.3 to 7.2) | 0.66 |
| ABMR, yes vs. no | 0.5 (−11.9 to 12.8) | 0.94 | 1.6 (−10.1 to 133) | 0.79 |
| Impact on recipient eGFR slope, mL/min/1.73 m2/year | ||||
| eGFR-dkc, per mL/min/1.73 m2 | Changes with each calculation | −0.1 (−0.3 to 0.1) | 0.27 | |
| Recipient variables | ||||
| Age, per year | 0.1 (0 to 0.2) | 0.26 | 0 (−0.1 to 0.1) | 0.39 |
| Female sex, yes vs. no | −2.1 (−5.2 to 1.1) | 0.20 | – | – |
| Preemptive transplantation, yes vs. no | 1.1 (−2.1 to 4.4) | 0.49 | – | – |
| Recipient of a re-transplant, yes vs. no | 0.9 (−4.2 to 6) | 0.73 | – | – |
| ABO/HLA incompatible transplantation, yes vs. no | −0.5 (−5.4 to 4.4) | 0.85 | – | – |
| Sum of HLA mismatch in A, B and DR, per n | 0.3 (−0.8 to 1.3) | 0.59 | – | – |
| IL-2R antibody induction, yes vs. no | 1.4 (−3.5 to 6.3) | 0.58 | – | – |
| Tacrolimus-based immunosuppression, yes vs. no | 2.5 (−1.4 to 6.4) | 0.20 | – | – |
| Belatacept-based immunosuppression, yes vs. no | −0.9 (−6.7 to 4.9) | 0.77 | – | – |
| LD variables | ||||
| Age, per year | −0.2 (−0.3 to 0) | 0.09 | −0.2 (−0.4 to 0) | 0.07 |
| Female sex, yes vs. no | 2.5 (−0.6 to 5.7) | 0.11 | 0.9 (−2.4 to 4.1) | 0.60 |
| BMI, per kg/m2 | −0.4 (−0.8 to −0.01) | 0.03 | −0.5 (−0.8 to −0) | 0.04 |
| Living-related, yes vs. no | −0.2 (−3.3 to 2.8) | 0.87 | – | – |
| Abnormal MTT of donated kidneyd, yes vs. no | 0.6 (−2.4 to 3.6) | 0.71 | 0.9 (−2.1 to 3.8) | 0.56 |
| Biopsy-proven rejection | ||||
| TCMR, yes vs. no | −2.8 (−6.5 to 0.9) | 0.13 | −1.2 (−4.9 to 2.5) | 0.51 |
| ABMR, yes vs. no | −5.3 (−10 to −0.6) | 0.03 | −5.8 (−10.4 to −1.2) | 0.01 |
ABMR antibody-mediated rejection, BMI body mass index, CI confidence interval, eGFR estimated glomerular filtration rate, eGFR-dk eGFR of the donated kidney, IL-2R interleukin‑2 receptor, LD live donor, MTT mean transit time, TCMR T cell-mediated rejection
aIn the reduced model recipient eGFR values from 6 to 36 months were used as dependent variable. eGFR-dk and time were included in each calculation. Other variables were added one by one. Slope estimates additionally considered interactions of variables with time
bThe multivariable model included eGFR-dk and time. Additionally, the model was expanded by variables with a P value of <0.157 for their impact on recipient baseline eGFR or its slope in the reduced model
ceGFR-dk was calculated from total donor eGFR on the basis of the relative kidney function determined in isotope nephrography
dMTT values of 1.9 to 2.9 min were considered normal