Preserved Kidney Function and Renal Recovery in Living Kidney Donors

Abstract

Background: Living kidney transplantation is considered the most favorable treatment for end-stage kidney disease. The aim of this study was to assess the impact of clinical pre-donation factors upon post-donation kidney function and renal recovery.

Methods: Sixty kidney donors (age = 46 ± 11 years, 63% women) were included. Associations between pre-donation factors and post-donation kidney function and renal recovery at 2 and 6 months were examined. Iohexol or ⁵¹Cr-EDTA was used to measure glomerular filtration rate. Multiple regression analyses and machine learning were applied.

Results: Pre-donation measured glomerular filtration rate (mGFR) was 107 ± 18 and single-kidney (sk) mGFR 55 ± 10 mL/min. Sk mGFR increased by 29% and 35% at 2 and 6 months, respectively (P < .001 vs pre-donation). In univariable regression analysis, age, female sex, mGFR₀, sk mGFR₀, eGFR₀, body surface area (BSA), triglycerides (TGs), high-density lipoprotein (HDL), and waist-hip ratio (WHR) were significantly associated with post-donation mGFR. Age and pre-donation mGFR were the main determinants of post-donation mGFR at 2 and 6 months (adjusted [adj.] R² = 0.64, F = 71.5 and adj. R² = 0.63, F = 51.6, respectively, P < .001 for both models). Renal recovery (∆mGFR 0-2 and 0-6 months post donation) was associated with age, sk mGFR, and side of the donated kidney (left vs right; adj. R² = 0.37 and R² = 0.44, respectively, P < .001 for both models). The findings were similar when applying machine learning (data not shown).

Conclusions: This study confirms that age and pre-donation kidney function (mGFR) are key determinants of post-donation kidney function and renal recovery.