Explore the scholarly record.

Abstract

Abstract Background: Nephron mass mismatch between donor kidney size and recipient body size has been suggested as a crucial determinant of long-term graft outcomes following kidney transplantation. However, large multicenter studies evaluating the combined impact of donor kidney weight and recipient body mass index (BMI) remain scarce. Methods: This retrospective multicenter cohort study encompassed 536 recipients who underwent living donor kidney transplantation from 1998 to 2021. Patients were stratified into four groups according to donor kidney weight (median, 200 g) and recipient BMI (cutoff, 25 kg/m²). Graft function decline, defined as the percentage change in estimated glomerular filtration rate from 1 month post-transplantation, was the primary outcome. Group comparisons were performed using analysis of variance with Tukey’s post-hoc test. Graft function decline-associated factors were evaluated using linear regression analyses. Results: In this multicenter cohort study, we demonstrated that the combination of donor kidney weight and recipient BMI was associated with long-term renal function decline following living donor kidney transplantation. Among these factors, donor kidney weight appeared to play a particularly important role in post-transplant renal outcomes (p = 0.0067). Multivariate analysis revealed that the combination of low donor kidney weight and high recipient BMI, rather than BMI alone, was independently associated with graft function decline (p = 0.0090). Furthermore, blood group incompatibility was identified as an independent predictor (p = 0.0016). Conclusions: The combination of donor kidney weight and recipient BMI was associated with long-term renal function decline following living donor kidney transplantation. These findings highlight the clinical significance of nephron mass matching in donor selection and recipient risk stratification.