Kidney Week

Abstract: SA-PO794

Progression of Kidney Disease in Kidney Transplant Recipients With a Failing Graft: A Matched Cohort Study

Session Information

• Transplantation: Clinical - Pretransplant Assessment and Living Donors
  November 05, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2002 Transplantation: Clinical

Authors

• Lam, Ngan, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Ngan Lam,

• Quinn, Robert R., University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Robert R. Quinn,

• Clarke, Alix, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Alix Clarke,

• Al-Wahsh, Huda, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Huda Al-Wahsh,

• Knoll, Greg A., Ottawa Hospital, Ottawa, Ontario, Canada

Greg A. Knoll,

• Kamar, Fareed, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Fareed Kamar,

• Jeong, Rachel, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Rachel Jeong,

• Kiberd, James Alan, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

James Alan Kiberd,

• Ravani, Pietro, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada

Pietro Ravani,

Background

Renal function may decline more rapidly in kidney transplant recipients with a failing graft than in people with chronic kidney disease (CKD) of their native kidneys.

Methods

We conducted a retrospective, population-based cohort study using linked healthcare databases in Alberta, Canada (2002-2019) to identify kidney transplant recipients with a failing graft, defined as 2 outpatient estimated glomerular filtration rate (eGFR) measurements between 15 and 30 mL/min/1.73 m² at least 90 days apart. Recipients were compared to propensity-score matched, non-transplant controls with a similar degree of sustained kidney dysfunction who were followed by a nephrologist. We compared the change in eGFR over time (primary outcome) and the competing risks of kidney failure and death without kidney failure (secondary outcome). We used joint modelling to account for possible informative censoring and the association between time-dependent changes in eGFR (eGFR with 95% confidence limits, _LCLeGFR_UCL) and the competing events (hazard ratios, _LCLHR_UCL).

Results

We matched 575 transplant recipients to 575 non-transplant controls. For the recipients, the median age was 57 years (interquartile range [IQR] 46-67), 39% were women, and median potential follow-up time was 7.8 years (IQR 3.6-12.1). In the joint model, the eGFR decline over time was similar in the two groups (recipients vs. controls: _-2.60-2.27_-1.94 vs. _-2.52-2.21_-1.90 mL/min/1.73 m² per year). In the time-to-event sub-model, the hazards for both kidney failure (HR _2.052.68_3.49) and death (HR _1.231.61_2.11) were significantly higher for transplant recipients. eGFR decline was associated with kidney failure but not with death.

Conclusion

Although kidney function declines at a similar rate in transplant recipients as in non-transplant controls, people with a failing graft have a higher risk of kidney failure and death. Studies are needed to identify preventive measures to improve outcomes in kidney transplant recipients with a failing graft.

Funding

• Government Support – Non-U.S.