Kidney Week

Abstract: TH-PO1175

Changes in Kidney Function After Live Donor Nephrectomy

Session Information

• Transplantation: Clinical - Pretransplant Management
  November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 1902 Transplantation: Clinical

Authors

• Lam, Ngan, University of Alberta, Edmonton, Alberta, Canada

Ngan Lam,

• Lloyd, Anita, University of Alberta, Edmonton, Alberta, Canada

Anita Lloyd,

• Lentine, Krista L., Saint Louis University, St. Louis, Missouri, United States

Krista L. Lentine,

• Quinn, Robert R., University of Calgary, Calgary, Alberta, Canada

Robert R. Quinn,

• Hemmelgarn, Brenda, University of Calgary, Calgary, Alberta, Canada

Brenda Hemmelgarn,

• Klarenbach, Scott, University of Alberta, Edmonton, Alberta, Canada

Scott Klarenbach,

• Garg, Amit X., London Health Sciences Centre, London, Ontario, Canada

Amit X. Garg,

Background

Better understanding the decline in kidney function after live donor nephrectomy and how this differs by donor characteristics can inform counselling, selection, and follow-up care.

Methods

We conducted a retrospective matched cohort study of living kidney donors in Alberta, Canada between 2002 and 2016 using linked healthcare administrative databases. We matched 604 donors to 2,414 healthy non-donors from the general population based on age, sex, year of cohort entry, urban residence, and estimated glomerular filtration rate (eGFR) before cohort entry (nephrectomy date for donors and randomly assigned date for non-donors). The primary outcome was rate of eGFR change over time (median follow-up 7 years, maximum 15 years).

Results

The median age was 43 years, 64% were women, and the baseline (predonation) eGFR was 100 mL/min/1.73 m². Overall, from 6 weeks onwards, the eGFR increased by +0.32 mL/min/1.73 m² per year (95% CI +0.17 to +0.46) in donors and decreased by -0.88 mL/min/1.73 m² per year (95% CI -0.96 to -0.79) in non-donors (p<0.001). The change in eGFR between 6 weeks to 2 years, 2 to 5 years, and ≥5 years onwards in donors was +1.05, +0.61, and -0.09 mL/min/1.73 m² per year, respectively. The change in eGFR over time in donors varied by sex, percent decline in eGFR within the first 6 weeks, and eGFR category at 1 year, but not by age category at donation, predonation hypertension, or predonation eGFR category.

Conclusion

The function in the remaining kidney of a living donor initially increases by 1 mL/min/1.73 m² per year due to hyperfiltration; however, this begins to plateau by 5 years postdonation. In contrast, non-donors experience a steady age-related decline of 1 mL/min/1.73 m² per year.

Mean estimated glomerular filtration rate (eGFR) over time in living kidney donors (solid line) and matched, healthy non-donor controls (dotted line).