Impact of Shared Decision Making in Renal Replacement Therapy Selection on Clinical Characteristics of Living-Donor Kidney Transplantation

1. Introduction

Among renal replacement therapy (RRT) modalities for patients with end-stage kidney disease, hemodialysis, peritoneal dialysis, and kidney transplantation are available. Of these, kidney transplantation is the most effective treatment, with clear advantages in survival and quality of life [1,2]. However, while deceased-donor kidney transplantation predominates in some countries, a shortage of deceased donors has led to dependence on living-donor kidney transplantation (LDKT) in Japan and many other countries [3]. To expand the indications for living donation, extensive basic and clinical research on ABO-incompatible kidney transplantation (ABOi-KT) has been conducted in Japan, with outcomes comparable to those of ABO-compatible transplantation [4]. Additionally, preemptive kidney transplantation (PEKT) has been increasingly performed in recent years. PEKT has been associated with improved graft survival and reduced cardiovascular events, with growing evidence from retrospective studies and meta-analyses [5].

Recently, patient-centered care has emphasized the importance of shared decision making (SDM), a process in which patients and clinicians collaboratively determine treatment options [6]. In the context of RRT, SDM has been shown to improve informed, patient-centered decision-making and patient satisfaction [7], with reports of increased selection of peritoneal dialysis and a higher proportion of patients undergoing pre-transplant evaluation following its introduction [8]. However, although some studies have described the influence of SDM on transplant selection, its impact on the clinical characteristics of transplantation remains unclear. Therefore, this study aimed to evaluate the influence of SDM implementation on the clinical characteristics of LDKT.

2. Materials and Methods

2.1. Shared Decision-Making Outpatient Clinic

A specialized SDM outpatient clinic was established at Fukuoka University Hospital in April 2019. Following routine chronic kidney disease (CKD) outpatient visits, patients were allocated approximately 60 minutes per session across two to three sessions, during which a dedicated nurse conducted structured information gathering and provided explanations about treatment options. In addition to written educational materials, patients and their families were offered hands-on exposure to peritoneal dialysis connection devices, automated peritoneal dialysis machines, educational DVDs, and tours of the hemodialysis unit. Treatment options were explained in the following order: kidney transplantation, peritoneal dialysis, and hemodialysis. Patients aged ≥75 years, those with untreatable malignancies, or those with severe cardiovascular comorbidities were considered unsuitable candidates for kidney transplantation. SDM was generally initiated when patients reached CKD stage G4 or G5, without strict numerical thresholds for the estimated glomerular filtration rate (eGFR), with the decision left to the attending nephrologist’s judgment.

2.2. Study Design and Participants

This retrospective cohort study included 65 patients who underwent LDKT between 2010 and 2025. Patients who received LDKT prior to the introduction of SDM were classified as the pre-SDM group (2010–2018, n = 25), and those thereafter were defined as the post-SDM group (2019–2025, n = 40). Donor and recipient demographic and clinical characteristics, transplant-related factors (ABOi-KT, donor-specific anti-HLA antibody [DSA] positivity, and PEKT), and preoperative kidney function (serum creatinine concentration and eGFR) were compared. eGFR was calculated using the equation developed for the Japanese population [9]. Hypertension was defined as a blood pressure of ≥140/90 mmHg at the outpatient clinic or treatment with antihypertensive drugs. Diabetes mellitus was defined as a fasting plasma glucose of ≥126 mg/dL, HbA1c of ≥6.5%, 2-hour plasma glucose of ≥200 mg/dL during a 75-g oral glucose tolerance test, or current use of hypoglycemic therapy. PEKT was defined as kidney transplantation performed prior to the initiation of maintenance dialysis; patients requiring temporary hemodialysis via a catheter for conditioning purposes were also included. In patients undergoing PEKT, kidney function at the initiation of evaluation and at admission for transplantation, as well as the need for preoperative hemodialysis, were assessed.

2.3. Statistical Analysis

Statistical analyses were performed using JMP Student Edition 18.2.1 (SAS Institute, Cary, NC, USA). Continuous variables were expressed as medians with interquartile ranges, and categorical variables were expressed as counts with percentages. Comparisons between the two groups were conducted using the Mann–Whitney U test for continuous variables and the chi-square test or Fisher’s exact test for categorical variables. A two-tailed P value of <0.05 was considered statistically significant. The study protocol was approved by the Ethics Committee of Fukuoka University Hospital (IRB H21-08-004), and all transplantations were performed in accordance with the Declaration of Istanbul. All living donors were either biologically related to the recipients (within the fourth degree of consanguinity) or were spouses, and were aged 18 years or older. No living unrelated donors were included in this study.

3. Results

Demographic and clinical characteristics of recipients and donors, as well as transplant-related factors, are summarized in Table 1, Table 2 and Table 3, respectively. Recipient age, sex, and primary kidney disease did not differ significantly between groups (Table 1). Donor age, however, was significantly higher in the post-SDM group than in the pre-SDM group (62.0 [52.3–68.0] vs. 55.0 [44.5–60.0] years, P = 0.01). No significant differences were observed between groups in donor hypertension, diabetes, or baseline kidney function (Table 2). The specific degree of relationship between donors and recipients is also summarized in Table 2.

With regard to transplant-related factors, the proportion of ABOi-KT was significantly higher in the post-SDM group (37.5% vs. 4.0%, P = 0.002). No DSA-positive transplantations were performed in the pre-SDM group, whereas they were performed in the post-SDM group (20.0%), showing a significant difference (P = 0.02) (Table 3).

Clinical characteristics of the patients who underwent PEKT are summarized separately in Table 4. The proportion of PEKT was comparable between the pre- and post-SDM groups (44.0% and 50.0%, respectively). However, initial eGFR at evaluation was significantly higher in the post-SDM group (11.4 [9.4–13.7] vs. 7.7 [7.1–9.5] mL/min/1.73 m², P = 0.01). The time from evaluation to transplantation was 118.0 [101.0–188.5] days in the pre-SDM group and 179.0 [119.0–243.0] days in the post-SDM group, without a significant difference. At admission for transplantation, eGFR was higher in the post-SDM group (8.7 [6.8–10.6] vs. 5.8 [4.9–7.3] mL/min/1.73 m², P = 0.006). Pre-transplant hemodialysis via a temporary catheter was performed in 54.5% of pre-SDM patients and 20.0% of post-SDM patients (P = 0.049).

4. Discussion

This study evaluated the impact of SDM introduction in RRT selection on the clinical characteristics of LDKT. We found that the introduction of SDM was associated with the acceptance of older living donors and higher frequencies of ABOi-KT and preformed DSA-positive kidney transplantation. Furthermore, among PEKT recipients, the post-SDM group underwent earlier pre-transplant evaluation, had better-preserved kidney function at admission, and less frequently required pre-transplant dialysis using a temporary catheter. To our knowledge, this is the first report describing an association between the implementation of SDM and the clinical characteristics of subsequent LDKT.

In Japan, the age at dialysis initiation has been steadily increasing [10], paralleled by increasing recipient age in transplantation [11]. In our study, although recipient age did not differ significantly, a slight upward trend was observed. Importantly, donor age was significantly higher in the post-SDM group, suggesting that SDM facilitated acceptance of older donors, likely through more comprehensive education and discussion with patients and families. When selecting RRT, insufficient patient knowledge may influence decision-making, leading to misconceptions about kidney transplantation. In particular, patients often self-exclude by assuming they are ineligible for kidney transplantation owing to factors such as age and comorbidities [12]. Furthermore, in Japan, limited understanding of ABOi-KT may also exist. These misconceptions may be addressed through appropriate information provision and sufficient time for SDM, which could ultimately improve access to kidney transplantation and expand its indications.

In addition, after the introduction of SDM, evaluation in PEKT cases was initiated earlier, and the rate of preoperative hemodialysis decreased, which is also an important finding. Kidney transplant recipients are typically patients with CKD stage G5, and evaluation of surgical tolerance is crucial, particularly screening for cardiovascular disease. Because postoperative immunosuppressive therapy is required, screening for malignancy and infections is also performed, aiming for curative treatment if detected, and vaccinations are administered when necessary. For donors, overall kidney function, cardiopulmonary and hepatic function, and the presence of infections or malignancies are assessed, along with psychological counseling to ensure long-term physical and mental safety after donation. If any problems are identified during this process, donor substitution is considered; indeed, in this study, donor changes were made in seven cases. The necessity of preoperative hemodialysis is determined individually, without clear criteria; however, it was performed when perioperative complications were anticipated, such as bleeding tendency due to uremia, fluid overload, or hyperkalemia. In our study, after the introduction of SDM, more PEKT procedures were performed without prior dialysis. This likely reduced risk associated with dialysis catheter insertion, such as infection and thrombosis, and supported safer transplantation.

In the selection of RRT, SDM is recognized as an effective approach that supports treatment choices aligned with patients’ values and lifestyles. Although patients with CKD face multiple treatment options, including hemodialysis, peritoneal dialysis, kidney transplantation, and conservative kidney management, SDM encourages collaborative dialogue between patients and healthcare providers, leading to improved satisfaction and adherence. Elwyn et al. [6] described SDM as a framework for patient-centered care and quality improvement in healthcare. Morton et al. [13] highlighted that decision-making in CKD is complex and often associated with anxiety and confusion, suggesting that improved decision support and SDM could be beneficial. Importantly, SDM has also been shown to promote selection of treatment modalities that have historically been underutilized, such as peritoneal dialysis and kidney transplantation. Patients who received SDM-based educational interventions were significantly more likely to select peritoneal dialysis and transplantation [7]. These findings suggest that SDM improves patients’ understanding of the benefits and limitations of each treatment modality, allowing them to make choices consistent with their personal values and lifestyles.

This study has several limitations. First, it was a single-center retrospective study with a small sample size, limiting statistical power and generalizability. Second, the pre-SDM and post-SDM groups were defined by calendar period. Consequently, secular changes in transplant practice—including increasing experience with ABOi-KT, DSA-positive transplantation, PEKT, and older living donors—may have contributed to the observed differences independently of SDM. The study design therefore cannot establish a causal effect of SDM. Third, only LDKT was analyzed, limiting applicability in countries where deceased-donor transplantation predominates. Fourth, preoperative dialysis decisions were physician-dependent, potentially introducing treatment-selection bias. Finally, unmeasured confounders such as socioeconomic status, education, and health literacy may have influenced outcomes. Future large-scale, prospective, and ideally randomized controlled studies are needed to confirm our findings. An ongoing randomized trial in Korea comparing SDM with standard care may provide further insights [14].

5. Conclusions

The introduction of a structured SDM outpatient clinic for RRT selection was associated with changes in the clinical characteristics and timing of LDKT at our center. After SDM implementation, transplantation involving older donors, ABO incompatibility, and preformed DSA positivity was more frequent. Among PEKT recipients, transplant evaluation began earlier in the course of kidney failure and preoperative dialysis was less frequently required. Because this historical pre–post study cannot separate the effect of SDM from secular changes in transplant practice, these findings should be interpreted as associations. Prospective studies are warranted to determine whether structured SDM can independently improve access to timely, patient-centered kidney transplantation.