Abstract: FR-PO1038

Limitation of Terminal Serum Creatinine as a KDPI Variable in Predicting Long-term Kidney Transplant Outcomes

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • Chopra, Bhavna, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States
  • Marcus, Richard J., Allegheny General Hospital, Pittsburgh, Pennsylvania, United States
  • Sureshkumar, Kalathil K., Allegheny General Hospital, Pittsburgh, Pennsylvania, United States
Background

Terminal serum creatinine (Cr) is a varible in deriving kidney donor profile index (KDPI) which is used for deceased donor kidney (DDK) allocation and predicting transplant outcomes. Terminal Cr is a dynamic variable and can increase from reversible causes. We hypothesize that transplantation of DDKs with higher terminal Cr within a KDPI group results in better long-term outcomes since these kidneys likely undergo procurement biopsy and transplant centers generally accept these kidneys only if the biopsy shows predominantly acute tubular injury with minimal chronicity.

Methods

Using the UNOS database, we identified adult DDK transplant recipients from 2000 to 2015 who received induction and were discharged on calcineurin inhibitor and mycophenolate mofetil maintenance.Patients were divided into 4 KDPI categories (0-20%, 21-50%, 51-85% and >85%). Using a Cox model, adjusted long-term graft and patient outcomes were compared between recipients of kidneys with terminal Cr >2.0 vs. ≤2.0 mg/dL under each KDPI category.

Results

Study comprised of 59,645 patients with a median follow up of 48 months. Adjusted graft and patient outcome comparisons based on terminal Cr for different KDPI groups are shown in the table. Adjusted overall graft failure and patient death risks were lower in patients who received DDKs with termial Cr >2 vs. ≤ 2 mg/dL in KDPI 21-50% and 51-85% groups but not in best quality (KDPI 0-20%) and marginal kidney (KDPI >85%) recipients. There were no differences in death-censored graft failure risks. Lower overall graft failure and similar death-censored graft failure in recipients of DDK with terminal Cr >2.0 mg/dL indicated reduced death with functioning graft.

Conclusion

The finding of reduced risk for death with functioning graft in patients who recieved DDK with termial Cr >2 mg/dL in the mid KDPI ranges likely reflects the selective use of these kidneys when procurment biopsy findings are favorable resulting in better long-term allograft function. Our study highlights limitations of using elevated terminal Cr in derivng KDPI.

Adjusted graft and patient outcomes by terminal creatinine (Cr) under different KDPI groups
 KDPI 0-20%
Cr >2; n=478;
Cr≤ 2; n=14769
KDP 21-50%
Cr >2; n=1592;
Cr≤2; n=17,762
KDPI 51-85%
Cr>2; n=1388;
Cr≤2; n=18,024
KDPI>85%
Cr >2; n=349;
Cr≤2; n=5282
 HR (95% CI)pHR (95% CI)pHR (95% CI)pHR (95% CI)p
Overall graft failure risk0.92 (0.75-1.14)0.460.88 (0.77-0.99)0.040.86 (0.76-0.96)0.0071.02 (0.86-1.21)0.85
Death-censored graft failure risk0.91(0.68-1.23)0.540.89 (0.75-1.05)0.170.91 (0.79-1.06)0.221.09 (0.88-1.37)0.43
Patient death risk0.88 (0.68-1.13)0.300.86 (0.74-0.99)0.040.84 (0.74-0.97)0.010.94 (0.76-1.16)0.58