What is the significance of end-stage renal disease risk estimation in living kidney donors?

Abstract

Two end-stage renal disease (ESRD) risk calculators were recently developed by Grams et al., and Ibrahim et al. to calculate ESRD risk before donation among living kidney donors. However, those calculators have never been studied among potential donors for whom donation was refused due to medical contraindications and compared to a group of donors. We compared 15-year and lifetime ESRD risk of donors and nondonors due to medical cause as estimated by those two calculators. Nondonors due to medical cause (n = 27) had a significantly higher 15-year ESRD risk compared to donors (n = 288) with both calculators (0.25 vs. 0.14, P < 0.001 for that developed by Grams et al. and 2.21 vs. 1.43, P = 0.002 for that developed by Ibrahim et al.). On the contrary, lifetime ESRD risk was not significantly different between the two groups. At both times (15 years and lifetime), we observed a significant overlap of ESRD risk between the two groups. ESRD risk calculators could be complementary to standard screening strategy but cannot be used alone to accept or decline donation.

Lifetime end-stage kidney disease risk estimation in living kidney donor candidates remains a challenge

“…Only the calculator by Grams et al [2] provides lifetime (albeit predonation) ESKD risk estimates and is endorsed by KDIGO. We read with interest the publication by Gaillard et al [5], having recently reported similar findings from Australia [6]. Like Gaillard et al, we observed higher predonation 15year risk but similar lifetime ESKD risk in declined compared with accepted LKDC using the Grams calculator.…”

“…We wish to emphasize the need for cautious use of the Ibrahim calculator [3] to estimate lifetime risk and highlight the paradoxical effect of donor age. Gaillard et al [5] reported higher 15-year but similar 40-year postdonation risk in their declined versus accepted LKDC using the Ibrahim calculator. As the median age was 10 years older in their declined LKDC, they were likely disadvantaged when 40-year postdonation risk was used to compare their long-term risk with accepted LKDC.…”

“…The Ibrahim calculator does not provide 40-year risk for male LKDC age over 61 (as donors were unlikely to have lived beyond 100 years of age), the likely explanation for the exclusion of their 10 declined LKDC. Furthermore, with a median age of 59 and an average life expectancy of 82 years in France [5], any risk estimation beyond 25 years would be inappropriate for the majority of their declined LKDC. In our cohort [6], we employed an alternative approach by reporting the postdonation risk at age 78-82 as a surrogate for lifetime risk.…”