Clinical Outcomes of Living Kidney Transplantation from Older Adult Donors Aged 70 Years and Older: A Multicenter Study of Seven Kidney Transplantation Centers in Japan

Clinical Outcomes of Living Kidney Transplantation from Older Adult Donors Aged 70 Years and Older: A Multicenter Study of Seven Kidney Transplantation Centers in Japan | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Clinical Outcomes of Living Kidney Transplantation from Older Adult Donors Aged 70 Years and Older: A Multicenter Study of Seven Kidney Transplantation Centers in Japan Ryohei Yamamoto, Mitsuru Saito, Tomohiko Matsuura, Shingo Hatakeyama, and 14 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7818024/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 18 Dec, 2025 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract The persistent organ shortage has led to the consideration of "marginal" donors, including those of advanced age, but the outcomes of using living kidney donors aged 70 years or older remain debated. This multicenter retrospective cohort study aimed to evaluate the propriety of kidney donation from older adult donors by analyzing the association between transplant outcomes and recipient age. Using data from 633 adult living-donor kidney transplants, we compared an elderly donor group (age ≥70 years, n=75) with a non-elderly donor group (age <70 years, n=558). After 1:1 propensity score matching, the elderly donor group showed significantly lower death-censored graft survival. However, this disadvantage disappeared entirely in recipients aged 50 years or older, who exhibited comparable death-censored graft survival to those with non-elderly donors ( p =0.743). In contrast, recipients younger than 50 years who received grafts from elderly donors had markedly inferior death-censored graft survival ( p =0.008). In conclusion, using living kidney donors aged ≥70 years is a viable strategy to expand the donor pool, but its success is influenced by recipient age. These results support an age-sensitive approach in counseling and decision-making for kidney transplantation. Health sciences/Health care Health sciences/Medical research Health sciences/Nephrology Living kidney donation Older adult donors Graft survival Age matching Propensity score matching Figures Figure 1 Figure 2 Figure 3 Introduction Kidney transplantation is the gold standard treatment for end-stage kidney disease, providing superior survival and quality of life compared with long-term dialysis ( 1 , 2 ). This advantage, including significant economic benefits over dialysis, extends to older adults ( 3 , 4 ). However, the persistent global organ shortage, a challenge that has spurred an increase in living donation worldwide to expand the organ pool, limits the application of kidney transplantation ( 5 ). In this context, international guidelines have evolved to cautiously include older individuals as living donors, who may have been previously considered unsuitable ( 6 ). In Japan, for instance, where the transplant-eligible population is rapidly aging, donors aged ≥ 70 years are frequently considered “marginal,” necessitating a careful evaluation of their associated outcomes ( 7 , 8 ). The use of organs from older donors has sparked considerable debate owing to concerns about risks for both the donor and the recipient ( 9 ). On the recipient side, a growing body of evidence indicates an association between increasing donor age and reduced long-term graft survival ( 10 ). This effect is particularly notable when a significant age mismatch exists between an older donor and a younger recipient ( 11 ). From the donor’s perspective, although the long-term risk of kidney failure appears low, other outcomes, such as the development of hypertension, warrant careful consideration ( 12 , 13 ). This growing awareness of the risks may slow the expansion of the older adult donor pool ( 9 ). While previous studies have suggested that advanced donor age impacts graft survival, particularly in cases of older donors and younger recipients ( 10 ), research focusing specifically on living donors aged 70 and over is scarce. Furthermore, few studies have quantitatively analyzed how transplant outcomes vary with recipient age using large-scale, real-world data from a multicenter cohort in Japan. A significant gap remains in identifying a specific recipient age threshold at which transplantation from an older adult donor may be considered acceptable. To address these outcome-related concerns, this study aimed to evaluate the clinical validity of using living donors aged ≥ 70 years. We here retrospectively analyzed clinical data to compare transplant outcomes for recipients of kidneys from an older adult donor group (≥ 70 years) with those from a non-older adult group (< 70 years) using a propensity score matching (PSM) analysis. Furthermore, we investigated donors’ postoperative kidney function and whether differences exist in clinical outcomes based on recipient age in kidney donations from older adult marginal donors. Results Baseline Characteristics Before PSM, the 633 recipients were categorized into the older adult (n = 75) and non-older adult (n = 558) donor groups. Recipient characteristics, including median age (48 vs. 49 years, p = 0.915) and sex distribution, were comparable between both groups. As defined by the group allocation, donors in the older adult group were significantly older (median, 72 vs. 57 years; p < 0.001), had a higher prevalence of hypertension (39% vs. 22%, p = 0.003), and a lower preoperative estimated glomerular filtration rate (eGFR) (median, 75.5 vs. 82.0 mL/min/1.73 m²; p = 0.003) (Table 1 ). Following 1:1 PSM, 69 matched pairs were identified. In this matched cohort, all recipient and donor baseline characteristics were well-balanced, with the standardized mean differences for all covariates being less than 0.01, except for the intended variable of donor age ( p < 0.001). Preoperative donor eGFR did not differ between the matched groups (median, 79.5 vs. 79.0 mL/min/1.73 m²; p = 0.587) (Table 2 ). Table 1 Baseline characteristics of recipients and donors stratified by donor age before propensity score matching Donor < 70 years Donor ≥ 70 years n = 558 n = 75 p -value Recipient Age (years), median (IQR) 49 (36–58) 48 (41–51) 0.915 Sex, male, n (%) 358 (64) 47 (63) 0.770 Preemptive, n (%) 137 ( 25 ) 20 ( 27 ) 0.671 Dialysis vintage (months), median (IQR) 14 (1–42) 12 (0.5–29) 0.366 DM, n (%) 113 ( 20 ) 9 ( 12 ) 0.118 Hypertension, n (%) 387 (69) 45 (60) 0.113 ABO-incompatible, n (%) 142 ( 25 ) 15 ( 20 ) 0.393 BMI (kg/m 2 ), median (IQR) 21.9 (19.8–24.7) 22.6 (20.2–24.5) 0.358 Follow-up period (months), median (IQR) 83 (46–137) 84 (35–143) 0.789 Donor Age (years), median (IQR) 57 (50–62) 72 (71–75) < 0.001 Sex, male, n (%) 218 (39) 37 (49) 0.103 BMI, median (IQR) 23.5 (21.2–25.8) 23.5 (21.8–26.0) 0.770 DM, n (%) 27 (48) 7 ( 9 ) 0.107 Hypertension, n (%) 123 ( 22 ) 29 (39) 0.003 eGFR (mL/min/1.73 m 2 ), median (IQR) 82.0 (73.3–94.0) 75.5 (66.9–87.8) 0.003 Table 2 Recipient and donor characteristics after 1:1 propensity score matching Donor < 70 years Donor ≥ 70 years n = 69 n = 69 p -value Recipient Age (years), median (IQR) 50 (34–58) 48 (42–51) 0.687 Sex, male, n (%) 36 (52) 44 (64) 0.227 Preemptive, n (%) 18 ( 26 ) 19 ( 28 ) 0.671 Dialysis vintage (months), median (IQR) 12 (0–52) 13 (0–31) 0.691 DM, n (%) 4 ( 6 ) 9( 13 ) 0.243 Hypertension, n (%) 37 (54) 42 (60) 0.491 ABO-incompatible, n (%) 17 ( 25 ) 15 ( 22 ) 0.840 BMI (kg/m 2 ), median (IQR) 22.5 (19.7–25.7) 22.6 (20.1–24.4) 0.816 Follow-up period (months), median (IQR) 88 (47–151) 93 (41–146) 0.606 Donor Age (years), median (IQR) 58 (53–62) 72 (71–75) < 0.001 Sex, male, n (%) 34 (49) 31(57) 0.733 BMI, median (IQR) 23.5 (21.2–25.8) 23.5 (21.8–26.0) 0.770 DM, n (%) 6 ( 9 ) 4 ( 6 ) 0.107 Hypertension, n (%) 24 (35) 24 (35) 1.000 eGFR (mL/min/1.73 m 2 ), median (IQR) 79 (69.4–87.6) 79.5 (67.9–88.9) 0.587 Abbreviations : IQR, interquartile range; DM, diabetes mellitus; BMI, body mass index; eGFR, estimated glomerular filtration rate. Note: The standardized mean differences for all baseline covariates were < 0.01 after matching. Graft Survival and Postoperative Renal Function of Recipients and Donors Before PSM, the older adult donor group exhibited significantly lower death-censored graft survival ( p < 0.001, Fig. 1 a), a difference that persisted even after matching ( p < 0.001, Fig. 2 a). In contrast, patient survival did not differ between the groups either before ( p = 0.880, Fig. 1 b) or after matching ( p = 0.647, Fig. 2 b). Regarding renal function, recipients from the older adult donor group exhibited consistently lower post-transplant eGFR at all follow-up points in both the unmatched (Fig. 1 c) and matched cohorts (Fig. 2 c). The donors showed a similar trend, with their post-donation eGFR being significantly lower in the older adult group in both the unmatched (Fig. 1 d) and matched analyses (Fig. 2 d) despite preoperative eGFR being balanced after matching. Complications Regardless of PSM, both groups exhibited comparable incidence of major complications. Throughout follow-up period, acute rejection developed in 40% and 38% of the older adult and non-older adult donor groups, respectively ( p = 0.702). Furthermore, rates of cytomegalovirus (CMV) infection, BK polyoma virus (BKPyV)-associated nephropathy, cardiovascular disease, and cancer development were comparable (Table 3 ). Table 3 Comparison of post-transplant complications between donor groups before propensity score matching Donor < 70 years Donor ≥ 70 years n = 558 n = 75 p -value Acute rejection, n (%) 210 (38) 30 (40) 0.702 CMV infection, n (%) 59 ( 11 ) 8 ( 11 ) 1 BKPyV-associated nephropathy, n (%) 30 ( 5 ) 7 ( 9 ) 0.186 Cardiovascular disease, n (%) 29 ( 5 ) 2 ( 3 ) 0.566 Cancer, n (%) 59 ( 11 ) 9 ( 12 ) 0.843 Subgroup Analysis Subgroup analysis based on recipient age was performed to assess its association with donor age and outcomes. Among recipients aged ≥ 50 years, no significant difference in death-censored graft survival was noted between those who received kidneys from older adult donors and those who received them from non-older adult donors ( p = 0.743, Fig. 3 ). In contrast, recipients aged < 50 years demonstrated significantly lower death-censored graft survival when the kidney was from an older adult donor ( p = 0.008, Fig. 3 ). Discussion This multicenter study reveals a crucial finding that although living kidney transplantation from donors aged ≥ 70 years is associated with inferior death-censored graft survival, this disadvantage seems to be completely dependent on recipient age. For recipients aged ≥ 50 years, kidneys from older adult donors offer comparable long-term graft survival to those from younger donors, strongly advocating for a strategy of donor–recipient age matching. Notably, despite successful PSM that balanced preoperative donor eGFR between the groups, recipients from older adult donors demonstrated consistently lower post-transplant renal function throughout the follow-up period. This finding suggests that chronological age captures kidney quality factors beyond what is reflected in baseline eGFR measurements, potentially encompassing subclinical nephrosclerosis, reduced regenerative capacity, and age-related changes in cellular function that are not evident in routine functional evaluations. The finding of reduced long-term graft survival from older donors aligns with the existing literature ( 10 – 12 , 14 ) and is likely multifactorial. Age-related nephrosclerosis, which leads to a lower functional nephron mass ( 15 ), combined with the effects of immunosenescence ( 16 ), may render these older kidneys more susceptible to injury. Our study refines this understanding by quantitatively determining an age threshold where this disadvantage may be mitigated. This phenomenon can be attributed to underlying biological concepts. Younger recipients exhibit higher long-term metabolic demands. The reduced nephron mass of an older kidney may be inadequate to meet these high demands over several decades. The persistent functional differences observed despite eGFR matching suggest that aging impacts kidney quality through mechanisms beyond nephron quantity. Age-related changes encompass mitochondrial dysfunction, cellular senescence, reduced angiogenic capacity, and altered response to injury—factors collectively compromising the kidney’s ability to maintain function and adapt to the metabolic demands of transplantation ( 17 ). Beyond recipient outcomes, donors’ postoperative kidney function constitutes a primary concern. In this study cohort, we confirmed that older adult donors experienced a safe perioperative course (data not shown). Regarding the surgical procedure, a previous study from our institution has demonstrated that hand-assisted retroperitoneoscopic living-donor nephrectomy is safe for older adult donors, with complication rates comparable to those of younger donors ( 18 ). This short-term safety profile is supported by broader literature offering reassuring evidence that with careful selection, donors aged > 70 years exhibit excellent long-term survival with a low absolute risk of end-stage renal disease development ( 8 , 19 – 21 ). Therefore, our findings should be interpreted alongside this evidence, suggesting the practice is ethically sound for both parties. In this study, donor kidney function in the older adult group after PSM did not reveal a tendency to decline up to 5 years postoperatively. However, the older adult group showed significantly lower donor kidney function than the non-older adult group throughout the immediate postoperative period. This result indicates a shortage of compensatory hyperfunction following nephrectomy in the older adult donors, which is also believed to influence graft function ( 22 ). The implications of this study are particularly salient for patient counseling and shared decision-making ( 23 , 24 ), especially in regions with rapidly aging populations, such as Japan ( 7 ). An older transplant candidate can be reassured that accepting a kidney from an age-matched older adult donor is a highly effective option that does not potentially compromise medium- to long-term graft survival ( 25 ). This finding offers robust evidence supporting the concept of “age-matching,” an approach shown to optimize outcomes ( 11 ) and agrees with the ethical principles of utility and equity in organ allocation ( 26 ). In the context of living kidney transplantation in Japan, where donations occur between a specific donor and recipient, the choice to reallocate donors on the basis of age is not available. However, our findings are pertinent in the decision-making process for individual transplant cases. For instance, when a recipient aged ≥ 50 years is considering whether to accept a kidney from a family member aged ≥ 70 years, this study provides the scientific evidence and reassurance that such matching does not compromise long-term graft survival, thereby facilitating their decision to proceed with transplantation. Therefore, these findings can enhance counseling with older recipients and their families, alleviating concerns about transplantation from older adult donors and optimizing transplantation opportunities. Conversely, when a 20-year-old recipient has both 45- and 70-year-old family members offering kidney donation, the kidney from the 45-year-old donor is ideal for situations where long-term primary graft survival is desired. Alternatively, using the 70-year-old family member as the first donor sets the stage for a potential second transplant. In this case, as the graft survival from the 70-year-old family member may be shorter, an appropriate counseling that encourages thorough self-management may be required to extend graft survival. This study had several limitations. First, the retrospective nature of our analysis precluded the establishment of causality ( 27 ). Although PSM can balance observed covariates, it cannot account for unmeasured or unknown confounders. Second, the study period spanned over two decades, during which immunosuppressive protocols and surgical techniques have evolved. Third, the database used in this study lacked data on the causes of graft loss, preventing an analysis of how donor age might influence the reasons for graft failure. Fourth, this study did not evaluate the histological markers of kidney aging, which may provide better predictors of post-transplant function than eGFR alone. Future studies incorporating kidney biopsy data or novel biomarkers of renal aging could further refine donor–recipient matching algorithms. Lastly, as the data were derived from a particular transplant network in Japan, the generalizability of our findings to other ethnic or geographic populations warrants further investigation. Despite these limitations, this study provides compelling real-world evidence from a large multicenter cohort demonstrating that chronological age functions as an essential surrogate for kidney quality beyond standard functional measures. The age-dependent outcomes strongly support age-based allocation strategy implementation for optimizing transplant outcomes and maximizing organ utilization ( 28 ). Conclusions This study demonstrated that although the use of living donors aged ≥ 70 years was associated with inferior overall graft survival, this effect was entirely driven by outcomes in younger recipients aged < 50 years. For recipients aged ≥ 50 years, graft survival was comparable to that from non-older adult donors, offering salient evidence for the effectiveness of using older adult donors in this population. Therefore, rather than advocating for a change in allocation that is not applicable to the living donation context, these results highlight the need for tailored counseling and shared decision-making that take patient age into account. This approach will facilitate maximizing the utility of every donated kidney by providing reassurance and a solid evidence base for older recipients considering transplantation from an older living donor. Furthermore, medical staff should educate younger recipients who received kidneys from older adult donors to protect the graft by implementing strict self-management. Methods Study Design and Population This retrospective cohort study analyzed 633 living-donor kidney transplants performed from May 1998 to December 2021 using the database from five hospitals and two tertiary hospitals (Michinoku Renal Transplant Network). This study was conducted across multiple transplant centers within the network. Patients were excluded from the analysis when they met any of the following criteria: (1) received a deceased donor, (2) were younger than 18 years old, (3) had a history of any organ transplants, or (4) had significant missing data required for the analysis. Recipients were divided into the following two groups on the basis of donor age: the older adult donor (≥ 70 years, n = 75) and non-older adult donor groups (< 70 years, n = 558). Ethical Approval This study was conducted in accordance with the principles of the Declaration of Helsinki. This study was approved by an ethics review board of the Akita University Graduate School of Medicine (Approval No. 2546) . All hospitals approved the present study. Data Collection Data on patient demographics, clinical characteristics, and transplant outcomes were collected from the database. For recipients, variables encompassed age, sex, preemptive transplantation status, dialysis duration, diabetes mellitus, primary disease, hypertension, ABO-incompatible transplantation, and body mass index (BMI). For donors, variables comprised age, sex, BMI, diabetes mellitus, hypertension, and eGFR. The eGFR was calculated using the formula adapted for Japanese individuals by the Japanese Society of Nephrology (29). Outcome Evaluations Patient survival and death-censored graft survival were evaluated before and after PSM. Death-censored graft survival was defined as the time from transplantation to the first graft loss occurrence from any cause other than the recipient’s death (e.g., return to dialysis, received second or third transplant, or graft removal). Moreover, renal function (eGFR) in both recipients and donors, as well as the incidence of complications (e.g., acute rejection, CMV infection, BK polyoma virus infection, cardiovascular disease, and cancer), were evaluated. Immunosuppressive Protocol The foundational immunosuppressive regimen comprised calcineurin inhibitors, mycophenolate mofetil, and corticosteroids. However, the target trough level, specific selection, and combination of these agents were determined at the discretion of the attending physician at each institution. Moreover, everolimus was prescribed at the discretion of the attending physician. For induction therapy, basiliximab was administered intraoperatively and on the fourth day postoperatively. For instances of ABO-incompatible kidney transplants or the presence of preformed donor-specific antibodies, rituximab and/or antibody removal were employed as part of the preoperative desensitization process. Diagnosis and Treatment of Acute Rejection Acute rejection was diagnosed on the basis of clinical and pathological data and guided by the Banff classification criteria, which have evolved over time. Each facility implemented treatment strategies at their discretion, tailoring care to individual patient needs. Statistical Analysis Continuous variables were expressed as medians with interquartile ranges and compared using the Mann–Whitney U test. Categorical variables were presented as frequencies and percentages and compared using the chi-square test or Fisher’s exact test as appropriate. We performed a PSM analysis to address potential selection bias and confounding inherent in a nonrandomized study. A 1:1 matching algorithm was employed to construct comparable cohorts of recipients from the older adult and non-older adult donor groups. The propensity score was calculated on the basis of key baseline characteristics of both the recipient (age, sex, BMI, ABO incompatibility, and diabetes) and the donor (sex, hypertension, diabetes, BMI, and eGFR). Following matching, 69 pairs were obtained for analysis. Survival analyses were performed using the Kaplan–Meier method, and differences between groups were assessed using the log-rank test. To evaluate the impact of donor–recipient age matching, subgroup analysis was performed on the basis of recipient age (<50 vs. ≥50 years). This age threshold was selected on the basis of previous findings （14）that identify this as a critical inflection point. All statistical analyses were performed using EZR (Easy R) (Saitama Medical Center, Jichi Medical University, Saitama, Japan), a graphical user interface for R. A P-value < 0.05 was considered statistically significant. Declarations Acknowledgments: We thank enago for the English language editing. Author Contributions: All authors contributed to the study design and/or assisted with data analysis and interpretation. All authors assisted in preparing the manuscript, reviewed the manuscript, and approved the manuscript for submission. All authors agree to be accountable for all the aspects of this study. Funding: None. Conflicts of interest: All authors declare no conflicts of interest. Consent to Participate: All patients provided written informed consent before undergoing any study-specific procedures. Consent for publication: Not applicable. Data Availability: The datasets generated and/or analyzed during the current study are not publicly available due to patient privacy protection but are available from the corresponding author on reasonable request. Code availability: Not applicable. Author Contributions: Ryohei Yamamoto and Mitsuru Saito had full access to all the data in the study and took responsibility for the integrity of the data and the accuracy of the data analysis. Conception and design: Ryohei Yamamoto, Mitsuru Saito, and Tomonori Habuchi. Data acquisition: Tomohiko Matsuura, Shingo Hatakeyama, Hayato Nishida, Shinya Maita, Kengo Furihata, Chika Kaziwara, Mizuki Mori, Yu Aoyama, Ayato Ito, Reiichi Murakami, Hirofumi Tomita, and Hisao Saitoh. Statistical analysis: Ryohei Yamamoto and Mitsuru Saito. Data analysis and interpretation: Ryohei Yamamoto and Mitsuru Saito. Drafting the manuscript: Ryohei Yamamoto and Mitsuru Saito. Supervision and critical revision of the manuscript for scientific and factual content: Tomohiko Matsuura, Shingo Hatakeyama, Hayato Nishida, Shinya Maita, Ayato Ito, Reiichi Murakami, Hirofumi Tomita, Hisao Saitoh, Norihiko Tsuchiya, Chikara Ohyama, Wataru Obara, and Tomonori Habuchi. Final approval of the manuscript: All authors. References Wolfe, R. A. et al. Comparison of mortality in all patients on dialysis, patients on dialysis awaiting transplantation, and recipients of a first cadaveric transplant. N. Engl. J. Med. 341 , 1725–1730 (1999). Garcia, G. G., Harden, P. & Chapman, J. The global role of kidney transplantation. Am. J. Nephrol. 35 , 259–264 (2012). Axelrod, D. A. et al. An economic assessment of contemporary kidney transplant practice. Am. J. Transplant. 18 , 1168–1176 (2018). Raissi, A., Bansal, A., Ekundayo, O. et al. Older age is associated with lower utilization of living donor kidney transplant. Kidney Int. Rep. 8 , 282–293 (2022). Matesanz, R., Mahillo, B. & Alvarez, M. Global observatory and database on donation and transplantation: world overview on transplantation activities. Transplant. Proc. 41 , 2297–2301 (2009). Lentine, K. L. et al. KDIGO Clinical practice guideline on the evaluation and care of living kidney donors. Transplantation 101 , S1–S109 (2017). Akikawa, A. Current status and future aspects of kidney transplantation in Japan. Ren. Replace. Ther. 4 , 50 (2018). Hiramitsu, T., Himeno, T., Hasegawa, Y. et al. Impact of age 70 years or older on donors for living-donor kidney transplantation. Kidney Int. Rep. 9 , 1321–1332 (2024). Basu, A. & Pasilan, R. M. F. Outcomes in LD70s redefining the limits of kidney donation: insights from living donors aged 70 years and older. Kidney Int. Rep. 9 , 1157–1159 (2024). Song, J. Y., Lee, K. W., Kim, K. et al. Recipient efficacy and safety of kidney transplantation from older living donor: consideration for using older kidney as a solution to the shortage of organs. Korean J. Transplant. 35 , 238–246 (2021). Molnar, M. Z., Streja, E., Kovesdy, C. P. et al. Age and the associations of living donor and expanded criteria donor kidneys with kidney transplant outcomes. Am. J. Kidney Dis. 59 , 841–848 (2012). Muzaale, A. D., Massie, A. B., Wang, M. C. et al. Risk of end-stage renal disease following live kidney donation. JAMA 311 , 579–586 (2014). Matas, A. J. & Rule, A. D. Long-term medical outcomes of living kidney donors. Mayo Clin. Proc. 97 , 2107–2122 (2022). Noppakun, K., Cosio, F. G., Dean, P. G. et al. Living donor age and kidney transplant outcomes. Am. J. Transplant. 11 , 1279–1286 (2011). Denic, A., Glassock, R. J. & Rule, A. D. Structural and functional changes with the aging kidney. Adv. Chronic Kidney Dis. 23 , 19–28 (2016). Heinbokel, T., Hock, K., Liu, G. et al. Impact of immunosenescence on transplant outcome. Transpl. Int. 26 , 242–253 (2013). Denic, A., Glassock, R. J. & Rule, A. D. The kidney in normal aging: a comparison with chronic kidney disease. Clin. J. Am. Soc. Nephrol. 17 , 137–139 (2022). Tsuchiya, N., Satoh, S., Sato, K. et al. Hand assisted retroperitoneoscopic living donor nephrectomy in elderly donors. J. Urol. 175 , 230–234 (2006). Gero, D., Dib, F., Matter, M. et al. Outcomes of kidney donors over 60 years old: a single-center cohort study. World J. Surg. 41 , 2940–2948 (2017). Berger, J. C., Muzaale, A. D., James, N. et al. Living kidney donors ages 70 and older: recipient and donor outcomes. Clin. J. Am. Soc. Nephrol. 6 , 2887–2893 (2011). Park, J. Y., Yang, W. J., Doo, S. W. et al. Long-term end-stage renal disease risks after living kidney donation: a systematic review and meta-analysis. BMC Nephrol. 24 , 152 (2023). Nishida, S., Hidaka, Y., Toyoda, M. et al. Factors related to suboptimal recovery of renal function after living donor nephrectomy: a retrospective study. BMC Nephrol. 20 , 403 (2019). Montori, V. M., Ruissen, M. M., Hargraves, I. G. et al. Shared decision-making as a method of care. BMJ Evid. Based Med. 28 , 213–217 (2023). Pinter, J., Hanson, C. S., Chapman, J. R. et al. Perspectives of older kidney transplant recipients on kidney transplantation. Clin. J. Am. Soc. Nephrol. 12 , 443–453 (2017). Bunnik, E. M. Ethics of allocation of donor organs. Curr. Opin. Organ Transplant. 28 , 192–196 (2023). Gutmann, T. & Land, W. The ethics of organ allocation: the state of debate. Transplant. Rev. (Orlando) 11 , 191–207 (1997). Concato, J., Shah, N. & Horwitz, R. I. Randomized, controlled trials, observational studies, and the hierarchy of research designs. N. Engl. J. Med. 342 , 1887–1892 (2000). Halloran, P. F., Melk, A. & Barth, C. Rethinking chronic allograft nephropathy: the concept of accelerated senescence. J. Am. Soc. Nephrol. 10 , 167–181 (1999). Matsuo, S. et al. Revised equations for estimated GFR from serum creatinine in Japan. Am. J. Kidney Dis. 53 , 982–992 (2009). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 18 Dec, 2025 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 21 Nov, 2025 Reviews received at journal 20 Nov, 2025 Reviews received at journal 13 Nov, 2025 Reviewers agreed at journal 02 Nov, 2025 Reviewers agreed at journal 01 Nov, 2025 Reviewers invited by journal 22 Oct, 2025 Editor assigned by journal 22 Oct, 2025 Editor invited by journal 17 Oct, 2025 Submission checks completed at journal 15 Oct, 2025 First submitted to journal 15 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7818024","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":538635100,"identity":"96919c8c-ef5b-4efe-8388-669a3d90f477","order_by":0,"name":"Ryohei Yamamoto","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Ryohei","middleName":"","lastName":"Yamamoto","suffix":""},{"id":538635101,"identity":"cf7b22e1-8c08-481c-a092-896df504653f","order_by":1,"name":"Mitsuru Saito","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxUlEQVRIiWNgGAWjYNACAwYGfhCdUEC8FgMGyQaQFgNSrDE4ALWOsNrbhw9/+FHwR874/OrEDw8MGOT5xQ4Q0HIuLU2yx8DA2OzG280SQIcZzpydQEDLGR4zBh4Dg8RtN85uAGlJMLhNWIvxxz9ALZtnnN38g1gtBtIgWzbw924jzhbJM2xp0jIGxsYSN3i3WSQYSBD2C98Z5sMf3/yRk+PvP7v55o8KG3l+aQJaEEACrFKCWOUgwH+AFNWjYBSMglEwkgAAG/5BFpu0qAUAAAAASUVORK5CYII=","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":true,"prefix":"","firstName":"Mitsuru","middleName":"","lastName":"Saito","suffix":""},{"id":538635102,"identity":"1a704867-7fea-4602-b398-0fd42e88a075","order_by":2,"name":"Tomohiko Matsuura","email":"","orcid":"","institution":"Hirosaki University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Tomohiko","middleName":"","lastName":"Matsuura","suffix":""},{"id":538635103,"identity":"dece3778-9f7f-48bb-a258-738a8f6b10bb","order_by":3,"name":"Shingo Hatakeyama","email":"","orcid":"","institution":"Hirosaki University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Shingo","middleName":"","lastName":"Hatakeyama","suffix":""},{"id":538635106,"identity":"f6380acb-cee1-46de-82ad-b7811f432f15","order_by":4,"name":"Hayato Nishida","email":"","orcid":"","institution":"Yamagata University Faculty of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Hayato","middleName":"","lastName":"Nishida","suffix":""},{"id":538635108,"identity":"ebd7e615-29c0-4465-a644-fa0fe478d39a","order_by":5,"name":"Shinya Maita","email":"","orcid":"","institution":"Iwate Prefectural Isawa Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shinya","middleName":"","lastName":"Maita","suffix":""},{"id":538635109,"identity":"079dfcfa-7a81-4cec-98e6-a7cec96c4818","order_by":6,"name":"Kengo Furihata","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Kengo","middleName":"","lastName":"Furihata","suffix":""},{"id":538635111,"identity":"5f059497-c932-40d3-8985-1a0a6812a0de","order_by":7,"name":"Chika Kaziwara","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Chika","middleName":"","lastName":"Kaziwara","suffix":""},{"id":538635113,"identity":"50346ec9-26cb-488d-80f9-e31d3fc0bdc3","order_by":8,"name":"Mizuki Mori","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Mizuki","middleName":"","lastName":"Mori","suffix":""},{"id":538635114,"identity":"d7c66014-75e8-44be-95a2-8085e488d3f5","order_by":9,"name":"Yu Aoyama","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Aoyama","suffix":""},{"id":538635115,"identity":"9ad665ea-1681-47c0-95ad-92898229f01f","order_by":10,"name":"Ayato Ito","email":"","orcid":"","institution":"Iwate Medical University","correspondingAuthor":false,"prefix":"","firstName":"Ayato","middleName":"","lastName":"Ito","suffix":""},{"id":538635116,"identity":"3297333a-4ad6-44ce-8d30-7849073e342c","order_by":11,"name":"Reiichi Murakami","email":"","orcid":"","institution":"Hirosaki University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Reiichi","middleName":"","lastName":"Murakami","suffix":""},{"id":538635117,"identity":"da9c7e65-c40e-4c0a-895d-3aedb3e91cbb","order_by":12,"name":"Hirofumi Tomita","email":"","orcid":"","institution":"Hirosaki University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Hirofumi","middleName":"","lastName":"Tomita","suffix":""},{"id":538635118,"identity":"c0bbcd4d-1300-49d9-9a2f-ca89673ee23d","order_by":13,"name":"Hisao Saitoh","email":"","orcid":"","institution":"Oyokyo Kidney Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Hisao","middleName":"","lastName":"Saitoh","suffix":""},{"id":538635119,"identity":"d8ca01dc-8791-4945-b4c1-1bd590d431bf","order_by":14,"name":"Norihiko Tsuchiya","email":"","orcid":"","institution":"Yamagata University Faculty of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Norihiko","middleName":"","lastName":"Tsuchiya","suffix":""},{"id":538635120,"identity":"f1b86d06-c850-4380-b10f-9071bce8a6e2","order_by":15,"name":"Chikara Ohyama","email":"","orcid":"","institution":"Hirosaki University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Chikara","middleName":"","lastName":"Ohyama","suffix":""},{"id":538635121,"identity":"8751771b-c552-4d7e-9914-111793d89b8a","order_by":16,"name":"Wataru Obara","email":"","orcid":"","institution":"Iwate Medical University","correspondingAuthor":false,"prefix":"","firstName":"Wataru","middleName":"","lastName":"Obara","suffix":""},{"id":538635122,"identity":"e14b86e3-1433-4ebb-a0d2-9a2a1789a167","order_by":17,"name":"Tomonori Habuchi","email":"","orcid":"","institution":"Akita University Graduate School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Tomonori","middleName":"","lastName":"Habuchi","suffix":""}],"badges":[],"createdAt":"2025-10-09 13:23:31","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7818024/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7818024/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-025-32558-x","type":"published","date":"2025-12-18T15:58:05+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":95223002,"identity":"8fd8bcbc-b81e-4669-9b14-00b2b95962fd","added_by":"auto","created_at":"2025-11-05 16:21:30","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6014610,"visible":true,"origin":"","legend":"","description":"","filename":"2025.10.14scientificreportselderlydonororiginalarticle.docx","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/7ecaca7680c0b1608e438329.docx"},{"id":95049132,"identity":"a8ef2b39-8b69-4d13-adeb-769a8bd4e144","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":16914,"visible":true,"origin":"","legend":"","description":"","filename":"a9395f8a49c041c487eec74d892d00b7.json","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/d2bf6ad6cfc8e69c495593a6.json"},{"id":95222575,"identity":"52fd0077-00d0-49e9-b9c3-575ba59fa441","added_by":"auto","created_at":"2025-11-05 16:20:50","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":96514,"visible":true,"origin":"","legend":"","description":"","filename":"a9395f8a49c041c487eec74d892d00b71enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/991195b458c3a3ba12573d41.xml"},{"id":95049138,"identity":"8b25046f-ede0-4734-a302-35e21ea5ba1d","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"jpeg","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":5616562,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/ddd1c675946e8f15e96dddd8.jpeg"},{"id":95049136,"identity":"c418c83d-8693-40bd-8331-e1ab75a043af","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"jpeg","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":222018,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/752c7c7e57310d614c60411a.jpeg"},{"id":95049133,"identity":"3e5ea090-c606-49e4-88fe-9d6cc0c8f281","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"jpeg","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":114652,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/9a1975fbbd5be319c14af9a7.jpeg"},{"id":95222819,"identity":"c7c329a0-4cfa-4110-923a-566833b384db","added_by":"auto","created_at":"2025-11-05 16:21:10","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":45309,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/2762eed6b487dd92fab2478c.png"},{"id":95049134,"identity":"ec46d51b-25e5-4c0b-99f5-5fd5eaf606ac","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":622084,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/f3a8c42580709863b2283258.png"},{"id":95222533,"identity":"edd4dcea-5742-4b8f-b3cf-36ed84b638b5","added_by":"auto","created_at":"2025-11-05 16:20:47","extension":"png","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":325071,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/49730a220e678e6fbc3fdbf8.png"},{"id":95049142,"identity":"814cd96d-e778-497a-803e-64dee278639d","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"xml","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":93380,"visible":true,"origin":"","legend":"","description":"","filename":"a9395f8a49c041c487eec74d892d00b71structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/8e1cb6d8cae9a951998734a8.xml"},{"id":95049140,"identity":"fe911212-1695-4eed-acc5-9a27ec8cd149","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":106811,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/3f92e1ef5ba661af5e850c06.html"},{"id":95049129,"identity":"639feae5-2f70-4ae7-94d0-8d81227809d2","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":45309,"visible":true,"origin":"","legend":"\u003cp\u003eDeath-censored graft survival (a), patient survival (b), and renal function in recipients (c) and donors (d) from older adult (≥ 70 years) versus non-older adult (\u0026lt; 70 years) living donors: unmatched cohort analysis\u003c/p\u003e\n\u003cp\u003eStatistical significance: * \u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05; time units: w = weeks, m = months, y = years; renal function measured as estimated glomerular filtration rate (eGFR, mL/min/1.73 m²)\u003c/p\u003e","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/f6db782eb1b1d6fa68dab4fe.png"},{"id":95223873,"identity":"ddc32295-4539-4478-ad9a-7e846ea2dd24","added_by":"auto","created_at":"2025-11-05 16:22:59","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":622084,"visible":true,"origin":"","legend":"\u003cp\u003ePropensity score-matched comparison of graft outcomes: impact of donor age on death-censored graft survival (a), patient survival (b), and long-term renal function of recipients (c) and donors (d)\u003c/p\u003e\n\u003cp\u003eStatistical significance: * \u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05; time units: w = weeks, m = months, y = years; renal function measured as estimated glomerular filtration rate (eGFR, mL/min/1.73 m²)\u003c/p\u003e","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/0de338992d9eec00044523ed.png"},{"id":95049130,"identity":"bfefbcf2-4011-4a24-ab0f-4f89008fb8a9","added_by":"auto","created_at":"2025-11-03 17:43:41","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":325071,"visible":true,"origin":"","legend":"\u003cp\u003eAge-dependent impact of older adult donors on death-censored graft survival: recipient age as a critical modifier of donor age effect in living kidney transplantation\u003c/p\u003e","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/08d2583f936204c9126af599.png"},{"id":100949288,"identity":"332cccdf-f8e2-4c81-8d73-9e7f6f416aa9","added_by":"auto","created_at":"2026-01-23 06:57:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2962258,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7818024/v1/6e2281da-4d50-4695-87ea-fe097dc3f9d5.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Clinical Outcomes of Living Kidney Transplantation from Older Adult Donors Aged 70 Years and Older: A Multicenter Study of Seven Kidney Transplantation Centers in Japan","fulltext":[{"header":"Introduction","content":"\u003cp\u003eKidney transplantation is the gold standard treatment for end-stage kidney disease, providing superior survival and quality of life compared with long-term dialysis (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). This advantage, including significant economic benefits over dialysis, extends to older adults (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). However, the persistent global organ shortage, a challenge that has spurred an increase in living donation worldwide to expand the organ pool, limits the application of kidney transplantation (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). In this context, international guidelines have evolved to cautiously include older individuals as living donors, who may have been previously considered unsuitable (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). In Japan, for instance, where the transplant-eligible population is rapidly aging, donors aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years are frequently considered \u0026ldquo;marginal,\u0026rdquo; necessitating a careful evaluation of their associated outcomes (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe use of organs from older donors has sparked considerable debate owing to concerns about risks for both the donor and the recipient (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). On the recipient side, a growing body of evidence indicates an association between increasing donor age and reduced long-term graft survival (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). This effect is particularly notable when a significant age mismatch exists between an older donor and a younger recipient (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). From the donor\u0026rsquo;s perspective, although the long-term risk of kidney failure appears low, other outcomes, such as the development of hypertension, warrant careful consideration (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). This growing awareness of the risks may slow the expansion of the older adult donor pool (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWhile previous studies have suggested that advanced donor age impacts graft survival, particularly in cases of older donors and younger recipients (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e), research focusing specifically on living donors aged 70 and over is scarce. Furthermore, few studies have quantitatively analyzed how transplant outcomes vary with recipient age using large-scale, real-world data from a multicenter cohort in Japan. A significant gap remains in identifying a specific recipient age threshold at which transplantation from an older adult donor may be considered acceptable.\u003c/p\u003e\u003cp\u003eTo address these outcome-related concerns, this study aimed to evaluate the clinical validity of using living donors aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years. We here retrospectively analyzed clinical data to compare transplant outcomes for recipients of kidneys from an older adult donor group (\u0026ge;\u0026thinsp;70 years) with those from a non-older adult group (\u0026lt;\u0026thinsp;70 years) using a propensity score matching (PSM) analysis. Furthermore, we investigated donors\u0026rsquo; postoperative kidney function and whether differences exist in clinical outcomes based on recipient age in kidney donations from older adult marginal donors.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eBaseline Characteristics\u003c/h2\u003e\u003cp\u003eBefore PSM, the 633 recipients were categorized into the older adult (n\u0026thinsp;=\u0026thinsp;75) and non-older adult (n\u0026thinsp;=\u0026thinsp;558) donor groups. Recipient characteristics, including median age (48 vs. 49 years, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.915) and sex distribution, were comparable between both groups. As defined by the group allocation, donors in the older adult group were significantly older (median, 72 vs. 57 years; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), had a higher prevalence of hypertension (39% vs. 22%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003), and a lower preoperative estimated glomerular filtration rate (eGFR) (median, 75.5 vs. 82.0 mL/min/1.73 m\u0026sup2;; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Following 1:1 PSM, 69 matched pairs were identified. In this matched cohort, all recipient and donor baseline characteristics were well-balanced, with the standardized mean differences for all covariates being less than 0.01, except for the intended variable of donor age (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Preoperative donor eGFR did not differ between the matched groups (median, 79.5 vs. 79.0 mL/min/1.73 m\u0026sup2;; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.587) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBaseline characteristics of recipients and donors stratified by donor age before propensity score matching\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026lt;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026ge;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;558\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRecipient\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (years), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e49 (36\u0026ndash;58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e48 (41\u0026ndash;51)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.915\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, male, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e358 (64)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e47 (63)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.770\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreemptive, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e137 (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20 (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.671\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDialysis vintage (months), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14 (1\u0026ndash;42)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e12 (0.5\u0026ndash;29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.366\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e113 (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9 (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.118\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e387 (69)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e45 (60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.113\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eABO-incompatible, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e142 (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e15 (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.393\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e21.9 (19.8\u0026ndash;24.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22.6 (20.2\u0026ndash;24.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.358\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFollow-up period (months), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e83 (46\u0026ndash;137)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e84 (35\u0026ndash;143)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.789\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDonor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (years), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e57 (50\u0026ndash;62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e72 (71\u0026ndash;75)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, male, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e218 (39)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37 (49)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.103\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI, median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23.5 (21.2\u0026ndash;25.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.5 (21.8\u0026ndash;26.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.770\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e27 (48)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.107\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e123 (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29 (39)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eeGFR (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e82.0 (73.3\u0026ndash;94.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e75.5 (66.9\u0026ndash;87.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eRecipient and donor characteristics after 1:1 propensity score matching\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026lt;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026ge;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRecipient\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (years), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e50 (34\u0026ndash;58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e48 (42\u0026ndash;51)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.687\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, male, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e36 (52)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e44 (64)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.227\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreemptive, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18 (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e19 (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.671\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDialysis vintage (months), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e12 (0\u0026ndash;52)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13 (0\u0026ndash;31)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.691\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4 (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.243\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e37 (54)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e42 (60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.491\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eABO-incompatible, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e17 (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e15 (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.840\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e22.5 (19.7\u0026ndash;25.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22.6 (20.1\u0026ndash;24.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.816\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFollow-up period (months), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e88 (47\u0026ndash;151)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e93 (41\u0026ndash;146)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.606\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDonor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (years), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e58 (53\u0026ndash;62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e72 (71\u0026ndash;75)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, male, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e34 (49)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e31(57)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.733\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI, median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23.5 (21.2\u0026ndash;25.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.5 (21.8\u0026ndash;26.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.770\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.107\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e24 (35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24 (35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.000\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eeGFR (mL/min/1.73 m\u003csup\u003e2\u003c/sup\u003e), median (IQR)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e79 (69.4\u0026ndash;87.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e79.5 (67.9\u0026ndash;88.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.587\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003cb\u003eAbbreviations\u003c/b\u003e: IQR, interquartile range; DM, diabetes mellitus; BMI, body mass index; eGFR, estimated glomerular filtration rate. Note: The standardized mean differences for all baseline covariates were \u0026lt;\u0026thinsp;0.01 after matching.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eGraft Survival and Postoperative Renal Function of Recipients and Donors\u003c/h3\u003e\n\u003cp\u003eBefore PSM, the older adult donor group exhibited significantly lower death-censored graft survival (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea), a difference that persisted even after matching (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). In contrast, patient survival did not differ between the groups either before (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.880, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb) or after matching (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.647, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eRegarding renal function, recipients from the older adult donor group exhibited consistently lower post-transplant eGFR at all follow-up points in both the unmatched (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec) and matched cohorts (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec). The donors showed a similar trend, with their post-donation eGFR being significantly lower in the older adult group in both the unmatched (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ed) and matched analyses (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed) despite preoperative eGFR being balanced after matching.\u003c/p\u003e\n\u003ch3\u003eComplications\u003c/h3\u003e\n\u003cp\u003eRegardless of PSM, both groups exhibited comparable incidence of major complications. Throughout follow-up period, acute rejection developed in 40% and 38% of the older adult and non-older adult donor groups, respectively (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.702). Furthermore, rates of cytomegalovirus (CMV) infection, BK polyoma virus (BKPyV)-associated nephropathy, cardiovascular disease, and cancer development were comparable (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of post-transplant complications between donor groups before propensity score matching\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026lt;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDonor\u0026thinsp;\u0026ge;\u0026thinsp;70 years\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;558\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAcute rejection, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e210 (38)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e30 (40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.702\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCMV infection, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e59 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBKPyV-associated nephropathy, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e30 (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.186\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCardiovascular disease, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29 (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.566\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCancer, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e59 (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9 (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.843\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eSubgroup Analysis\u003c/h3\u003e\n\u003cp\u003eSubgroup analysis based on recipient age was performed to assess its association with donor age and outcomes. Among recipients aged\u0026thinsp;\u0026ge;\u0026thinsp;50 years, no significant difference in death-censored graft survival was noted between those who received kidneys from older adult donors and those who received them from non-older adult donors (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.743, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). In contrast, recipients aged\u0026thinsp;\u0026lt;\u0026thinsp;50 years demonstrated significantly lower death-censored graft survival when the kidney was from an older adult donor (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.008, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis multicenter study reveals a crucial finding that although living kidney transplantation from donors aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years is associated with inferior death-censored graft survival, this disadvantage seems to be completely dependent on recipient age. For recipients aged\u0026thinsp;\u0026ge;\u0026thinsp;50 years, kidneys from older adult donors offer comparable long-term graft survival to those from younger donors, strongly advocating for a strategy of donor\u0026ndash;recipient age matching. Notably, despite successful PSM that balanced preoperative donor eGFR between the groups, recipients from older adult donors demonstrated consistently lower post-transplant renal function throughout the follow-up period. This finding suggests that chronological age captures kidney quality factors beyond what is reflected in baseline eGFR measurements, potentially encompassing subclinical nephrosclerosis, reduced regenerative capacity, and age-related changes in cellular function that are not evident in routine functional evaluations.\u003c/p\u003e\u003cp\u003eThe finding of reduced long-term graft survival from older donors aligns with the existing literature (\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) and is likely multifactorial. Age-related nephrosclerosis, which leads to a lower functional nephron mass (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e), combined with the effects of immunosenescence (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e), may render these older kidneys more susceptible to injury. Our study refines this understanding by quantitatively determining an age threshold where this disadvantage may be mitigated. This phenomenon can be attributed to underlying biological concepts.\u003c/p\u003e\u003cp\u003eYounger recipients exhibit higher long-term metabolic demands. The reduced nephron mass of an older kidney may be inadequate to meet these high demands over several decades. The persistent functional differences observed despite eGFR matching suggest that aging impacts kidney quality through mechanisms beyond nephron quantity. Age-related changes encompass mitochondrial dysfunction, cellular senescence, reduced angiogenic capacity, and altered response to injury\u0026mdash;factors collectively compromising the kidney\u0026rsquo;s ability to maintain function and adapt to the metabolic demands of transplantation (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eBeyond recipient outcomes, donors\u0026rsquo; postoperative kidney function constitutes a primary concern. In this study cohort, we confirmed that older adult donors experienced a safe perioperative course (data not shown). Regarding the surgical procedure, a previous study from our institution has demonstrated that hand-assisted retroperitoneoscopic living-donor nephrectomy is safe for older adult donors, with complication rates comparable to those of younger donors (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). This short-term safety profile is supported by broader literature offering reassuring evidence that with careful selection, donors aged\u0026thinsp;\u0026gt;\u0026thinsp;70 years exhibit excellent long-term survival with a low absolute risk of end-stage renal disease development (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). Therefore, our findings should be interpreted alongside this evidence, suggesting the practice is ethically sound for both parties. In this study, donor kidney function in the older adult group after PSM did not reveal a tendency to decline up to 5 years postoperatively. However, the older adult group showed significantly lower donor kidney function than the non-older adult group throughout the immediate postoperative period. This result indicates a shortage of compensatory hyperfunction following nephrectomy in the older adult donors, which is also believed to influence graft function (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe implications of this study are particularly salient for patient counseling and shared decision-making (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e), especially in regions with rapidly aging populations, such as Japan (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). An older transplant candidate can be reassured that accepting a kidney from an age-matched older adult donor is a highly effective option that does not potentially compromise medium- to long-term graft survival (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e). This finding offers robust evidence supporting the concept of \u0026ldquo;age-matching,\u0026rdquo; an approach shown to optimize outcomes (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e) and agrees with the ethical principles of utility and equity in organ allocation (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). In the context of living kidney transplantation in Japan, where donations occur between a specific donor and recipient, the choice to reallocate donors on the basis of age is not available. However, our findings are pertinent in the decision-making process for individual transplant cases. For instance, when a recipient aged\u0026thinsp;\u0026ge;\u0026thinsp;50 years is considering whether to accept a kidney from a family member aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years, this study provides the scientific evidence and reassurance that such matching does not compromise long-term graft survival, thereby facilitating their decision to proceed with transplantation. Therefore, these findings can enhance counseling with older recipients and their families, alleviating concerns about transplantation from older adult donors and optimizing transplantation opportunities. Conversely, when a 20-year-old recipient has both 45- and 70-year-old family members offering kidney donation, the kidney from the 45-year-old donor is ideal for situations where long-term primary graft survival is desired. Alternatively, using the 70-year-old family member as the first donor sets the stage for a potential second transplant. In this case, as the graft survival from the 70-year-old family member may be shorter, an appropriate counseling that encourages thorough self-management may be required to extend graft survival.\u003c/p\u003e\u003cp\u003eThis study had several limitations. First, the retrospective nature of our analysis precluded the establishment of causality (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). Although PSM can balance observed covariates, it cannot account for unmeasured or unknown confounders. Second, the study period spanned over two decades, during which immunosuppressive protocols and surgical techniques have evolved. Third, the database used in this study lacked data on the causes of graft loss, preventing an analysis of how donor age might influence the reasons for graft failure. Fourth, this study did not evaluate the histological markers of kidney aging, which may provide better predictors of post-transplant function than eGFR alone. Future studies incorporating kidney biopsy data or novel biomarkers of renal aging could further refine donor\u0026ndash;recipient matching algorithms. Lastly, as the data were derived from a particular transplant network in Japan, the generalizability of our findings to other ethnic or geographic populations warrants further investigation. Despite these limitations, this study provides compelling real-world evidence from a large multicenter cohort demonstrating that chronological age functions as an essential surrogate for kidney quality beyond standard functional measures. The age-dependent outcomes strongly support age-based allocation strategy implementation for optimizing transplant outcomes and maximizing organ utilization (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study demonstrated that although the use of living donors aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years was associated with inferior overall graft survival, this effect was entirely driven by outcomes in younger recipients aged\u0026thinsp;\u0026lt;\u0026thinsp;50 years. For recipients aged\u0026thinsp;\u0026ge;\u0026thinsp;50 years, graft survival was comparable to that from non-older adult donors, offering salient evidence for the effectiveness of using older adult donors in this population.\u003c/p\u003e\u003cp\u003eTherefore, rather than advocating for a change in allocation that is not applicable to the living donation context, these results highlight the need for tailored counseling and shared decision-making that take patient age into account. This approach will facilitate maximizing the utility of every donated kidney by providing reassurance and a solid evidence base for older recipients considering transplantation from an older living donor. Furthermore, medical staff should educate younger recipients who received kidneys from older adult donors to protect the graft by implementing strict self-management.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eStudy Design and Population\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective cohort study analyzed 633 living-donor kidney transplants performed from May 1998 to December 2021 using the database from five hospitals and two tertiary hospitals (Michinoku Renal Transplant Network). This study was conducted across multiple transplant centers within the network. Patients were excluded from the analysis when they met any of the following criteria: (1) received a deceased donor, (2) were younger than 18 years old, (3) had a history of any organ transplants, or (4) had significant missing data required for the analysis. Recipients were divided into the following two groups on the basis of donor age: the older adult donor (≥ 70 years, n = 75) and non-older adult donor groups (\u0026lt; 70 years, n = 558).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the principles of the Declaration of Helsinki. This study was approved by an ethics review board of the Akita University Graduate School of Medicine (Approval No. 2546)\u003cstrong\u003e.\u0026nbsp;\u003c/strong\u003eAll hospitals approved the present study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData on patient demographics, clinical characteristics, and transplant outcomes were collected from the database. For recipients, variables encompassed age, sex, preemptive transplantation status, dialysis duration, diabetes mellitus, primary disease, hypertension, ABO-incompatible transplantation, and body mass index (BMI). For donors, variables comprised age, sex, BMI, diabetes mellitus, hypertension, and eGFR. The eGFR was calculated using the formula adapted for Japanese individuals by the Japanese Society of Nephrology (29).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutcome\u003c/strong\u003e \u003cstrong\u003eEvaluations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatient survival and death-censored graft survival were evaluated before and after PSM. Death-censored graft survival was defined as the time from transplantation to the first graft loss occurrence from any cause other than the recipient’s death (e.g., return to dialysis, received second or third transplant, or graft removal). Moreover, renal function (eGFR) in both recipients and donors, as well as the incidence of complications (e.g., acute rejection, CMV infection, BK polyoma virus infection, cardiovascular disease, and cancer), were evaluated.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eImmunosuppressive Protocol\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe foundational immunosuppressive regimen comprised calcineurin inhibitors, mycophenolate mofetil, and corticosteroids. However, the target trough level, specific selection, and combination of these agents were determined at the discretion of the attending physician at each institution. Moreover, everolimus was prescribed at the discretion of the attending physician. For induction therapy, basiliximab was administered intraoperatively and on the fourth day postoperatively. For instances of ABO-incompatible kidney transplants or the presence of preformed donor-specific antibodies, rituximab and/or antibody removal were employed as part of the preoperative desensitization process.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiagnosis and Treatment of Acute Rejection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAcute rejection was diagnosed on the basis of clinical and pathological data and guided by the Banff classification criteria, which have evolved over time. Each facility implemented treatment strategies at their discretion, tailoring care to individual patient needs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eContinuous variables were expressed as medians with interquartile ranges and compared using the Mann–Whitney U test. Categorical variables were presented as frequencies and percentages and compared using the chi-square test or Fisher’s exact test as appropriate. We performed a PSM analysis to address potential selection bias and confounding inherent in a nonrandomized study. A 1:1 matching algorithm was employed to construct comparable cohorts of recipients from the older adult and non-older adult donor groups. The propensity score was calculated on the basis of key baseline characteristics of both the recipient (age, sex, BMI, ABO incompatibility, and diabetes) and the donor (sex, hypertension, diabetes, BMI, and eGFR). Following matching, 69 pairs were obtained for analysis. Survival analyses were performed using the Kaplan–Meier method, and differences between groups were assessed using the log-rank test.\u003c/p\u003e\n\u003cp\u003eTo evaluate the impact of donor–recipient age matching, subgroup analysis was performed on the basis of recipient age (\u0026lt;50 vs. ≥50 years). This age threshold was selected on the basis of previous findings\u0026nbsp;（14）that identify this as a critical inflection point.\u003c/p\u003e\n\u003cp\u003eAll statistical analyses were performed using EZR (Easy R) (Saitama Medical Center, Jichi Medical University, Saitama, Japan), a graphical user interface for R. A P-value \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments: \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank enago for the English language editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u0026nbsp;\u003c/strong\u003eAll authors contributed to the study design and/or assisted with data analysis and interpretation. All authors assisted in preparing the manuscript, reviewed the manuscript, and approved the manuscript for submission. All authors agree to be accountable for all the aspects of this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest: All authors declare no conflicts of interest.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate:\u0026nbsp;\u003c/strong\u003eAll patients provided written informed consent before undergoing any study-specific procedures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability:\u0026nbsp;\u003c/strong\u003eThe datasets generated and/or analyzed during the current study are not publicly available due to patient privacy protection but are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCode availability:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRyohei Yamamoto and Mitsuru Saito had full access to all the data in the study and took responsibility for the integrity of the data and the accuracy of the data analysis.\u003c/p\u003e\n\u003cp\u003eConception and design: Ryohei Yamamoto, Mitsuru Saito, and Tomonori Habuchi.\u003c/p\u003e\n\u003cp\u003eData acquisition:\u0026nbsp;Tomohiko Matsuura, Shingo Hatakeyama, Hayato Nishida, Shinya Maita, Kengo Furihata, Chika Kaziwara, Mizuki Mori, Yu Aoyama, Ayato Ito, Reiichi Murakami, Hirofumi Tomita, and Hisao Saitoh.\u003c/p\u003e\n\u003cp\u003eStatistical analysis: Ryohei Yamamoto and Mitsuru Saito.\u003c/p\u003e\n\u003cp\u003eData analysis and interpretation: Ryohei Yamamoto and Mitsuru Saito.\u003c/p\u003e\n\u003cp\u003eDrafting the manuscript: Ryohei Yamamoto and Mitsuru Saito.\u003c/p\u003e\n\u003cp\u003eSupervision and critical revision of the manuscript for scientific and factual content:\u0026nbsp;Tomohiko Matsuura, Shingo Hatakeyama, Hayato Nishida, Shinya Maita, Ayato Ito, Reiichi Murakami, Hirofumi Tomita, Hisao Saitoh, Norihiko Tsuchiya, Chikara Ohyama, Wataru Obara,\u0026nbsp;and Tomonori Habuchi.\u003c/p\u003e\n\u003cp\u003eFinal approval of the manuscript: All authors.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eWolfe, R. A. \u003cem\u003eet al.\u003c/em\u003e Comparison of mortality in all patients on dialysis, patients on dialysis awaiting transplantation, and recipients of a first cadaveric transplant. \u003cem\u003eN. Engl. J. Med.\u003c/em\u003e\u003cstrong\u003e341\u003c/strong\u003e, 1725\u0026ndash;1730 (1999).\u003c/li\u003e\n\u003cli\u003eGarcia, G. G., Harden, P. \u0026amp; Chapman, J. The global role of kidney transplantation. \u003cem\u003eAm. J. Nephrol.\u003c/em\u003e\u003cstrong\u003e35\u003c/strong\u003e, 259\u0026ndash;264 (2012).\u003c/li\u003e\n\u003cli\u003eAxelrod, D. A. \u003cem\u003eet al.\u003c/em\u003e An economic assessment of contemporary kidney transplant practice. \u003cem\u003eAm. J. Transplant.\u003c/em\u003e\u003cstrong\u003e18\u003c/strong\u003e, 1168\u0026ndash;1176 (2018).\u003c/li\u003e\n\u003cli\u003eRaissi, A., Bansal, A., Ekundayo, O. \u003cem\u003eet al.\u003c/em\u003e Older age is associated with lower utilization of living donor kidney transplant. \u003cem\u003eKidney Int. Rep.\u003c/em\u003e\u003cstrong\u003e8\u003c/strong\u003e, 282\u0026ndash;293 (2022).\u003c/li\u003e\n\u003cli\u003eMatesanz, R., Mahillo, B. \u0026amp; Alvarez, M. Global observatory and database on donation and transplantation: world overview on transplantation activities. \u003cem\u003eTransplant. Proc.\u003c/em\u003e\u003cstrong\u003e41\u003c/strong\u003e, 2297\u0026ndash;2301 (2009).\u003c/li\u003e\n\u003cli\u003eLentine, K. L. \u003cem\u003eet al.\u003c/em\u003e KDIGO Clinical practice guideline on the evaluation and care of living kidney donors. \u003cem\u003eTransplantation\u003c/em\u003e\u003cstrong\u003e101\u003c/strong\u003e, S1\u0026ndash;S109 (2017).\u003c/li\u003e\n\u003cli\u003eAkikawa, A. Current status and future aspects of kidney transplantation in Japan. \u003cem\u003eRen. Replace. Ther.\u003c/em\u003e\u003cstrong\u003e4\u003c/strong\u003e, 50 (2018).\u003c/li\u003e\n\u003cli\u003eHiramitsu, T., Himeno, T., Hasegawa, Y. \u003cem\u003eet al.\u003c/em\u003e Impact of age 70 years or older on donors for living-donor kidney transplantation. \u003cem\u003eKidney Int. Rep.\u003c/em\u003e\u003cstrong\u003e9\u003c/strong\u003e, 1321\u0026ndash;1332 (2024).\u003c/li\u003e\n\u003cli\u003eBasu, A. \u0026amp; Pasilan, R. M. F. Outcomes in LD70s redefining the limits of kidney donation: insights from living donors aged 70 years and older. \u003cem\u003eKidney Int. Rep.\u003c/em\u003e\u003cstrong\u003e9\u003c/strong\u003e, 1157\u0026ndash;1159 (2024).\u003c/li\u003e\n\u003cli\u003eSong, J. Y., Lee, K. W., Kim, K. \u003cem\u003eet al.\u003c/em\u003e Recipient efficacy and safety of kidney transplantation from older living donor: consideration for using older kidney as a solution to the shortage of organs. \u003cem\u003eKorean J. Transplant.\u003c/em\u003e\u003cstrong\u003e35\u003c/strong\u003e, 238\u0026ndash;246 (2021).\u003c/li\u003e\n\u003cli\u003eMolnar, M. Z., Streja, E., Kovesdy, C. P. \u003cem\u003eet al.\u003c/em\u003e Age and the associations of living donor and expanded criteria donor kidneys with kidney transplant outcomes. \u003cem\u003eAm. J. Kidney Dis.\u003c/em\u003e\u003cstrong\u003e59\u003c/strong\u003e, 841\u0026ndash;848 (2012).\u003c/li\u003e\n\u003cli\u003eMuzaale, A. D., Massie, A. B., Wang, M. C. \u003cem\u003eet al.\u003c/em\u003e Risk of end-stage renal disease following live kidney donation. \u003cem\u003eJAMA\u003c/em\u003e\u003cstrong\u003e311\u003c/strong\u003e, 579\u0026ndash;586 (2014).\u003c/li\u003e\n\u003cli\u003eMatas, A. J. \u0026amp; Rule, A. D. Long-term medical outcomes of living kidney donors. \u003cem\u003eMayo Clin. Proc.\u003c/em\u003e\u003cstrong\u003e97\u003c/strong\u003e, 2107\u0026ndash;2122 (2022).\u003c/li\u003e\n\u003cli\u003eNoppakun, K., Cosio, F. G., Dean, P. G. \u003cem\u003eet al.\u003c/em\u003e Living donor age and kidney transplant outcomes. \u003cem\u003eAm. J. Transplant.\u003c/em\u003e\u003cstrong\u003e11\u003c/strong\u003e, 1279\u0026ndash;1286 (2011).\u003c/li\u003e\n\u003cli\u003eDenic, A., Glassock, R. J. \u0026amp; Rule, A. D. Structural and functional changes with the aging kidney. \u003cem\u003eAdv. Chronic Kidney Dis.\u003c/em\u003e\u003cstrong\u003e23\u003c/strong\u003e, 19\u0026ndash;28 (2016).\u003c/li\u003e\n\u003cli\u003eHeinbokel, T., Hock, K., Liu, G. \u003cem\u003eet al.\u003c/em\u003e Impact of immunosenescence on transplant outcome. \u003cem\u003eTranspl. Int.\u003c/em\u003e\u003cstrong\u003e26\u003c/strong\u003e, 242\u0026ndash;253 (2013).\u003c/li\u003e\n\u003cli\u003eDenic, A., Glassock, R. J. \u0026amp; Rule, A. D. The kidney in normal aging: a comparison with chronic kidney disease. \u003cem\u003eClin. J. Am. Soc. Nephrol.\u003c/em\u003e\u003cstrong\u003e17\u003c/strong\u003e, 137\u0026ndash;139 (2022).\u003c/li\u003e\n\u003cli\u003eTsuchiya, N., Satoh, S., Sato, K. \u003cem\u003eet al.\u003c/em\u003e Hand assisted retroperitoneoscopic living donor nephrectomy in elderly donors. \u003cem\u003eJ. Urol.\u003c/em\u003e\u003cstrong\u003e175\u003c/strong\u003e, 230\u0026ndash;234 (2006).\u003c/li\u003e\n\u003cli\u003eGero, D., Dib, F., Matter, M. \u003cem\u003eet al.\u003c/em\u003e Outcomes of kidney donors over 60 years old: a single-center cohort study. \u003cem\u003eWorld J. Surg.\u003c/em\u003e\u003cstrong\u003e41\u003c/strong\u003e, 2940\u0026ndash;2948 (2017).\u003c/li\u003e\n\u003cli\u003eBerger, J. C., Muzaale, A. D., James, N. \u003cem\u003eet al.\u003c/em\u003e Living kidney donors ages 70 and older: recipient and donor outcomes. \u003cem\u003eClin. J. Am. Soc. Nephrol.\u003c/em\u003e\u003cstrong\u003e6\u003c/strong\u003e, 2887\u0026ndash;2893 (2011).\u003c/li\u003e\n\u003cli\u003ePark, J. Y., Yang, W. J., Doo, S. W. \u003cem\u003eet al.\u003c/em\u003e Long-term end-stage renal disease risks after living kidney donation: a systematic review and meta-analysis. \u003cem\u003eBMC Nephrol.\u003c/em\u003e\u003cstrong\u003e24\u003c/strong\u003e, 152 (2023).\u003c/li\u003e\n\u003cli\u003eNishida, S., Hidaka, Y., Toyoda, M. \u003cem\u003eet al.\u003c/em\u003e Factors related to suboptimal recovery of renal function after living donor nephrectomy: a retrospective study. \u003cem\u003eBMC Nephrol.\u003c/em\u003e\u003cstrong\u003e20\u003c/strong\u003e, 403 (2019).\u003c/li\u003e\n\u003cli\u003eMontori, V. M., Ruissen, M. M., Hargraves, I. G. \u003cem\u003eet al.\u003c/em\u003e Shared decision-making as a method of care. \u003cem\u003eBMJ Evid. Based Med.\u003c/em\u003e\u003cstrong\u003e28\u003c/strong\u003e, 213\u0026ndash;217 (2023).\u003c/li\u003e\n\u003cli\u003ePinter, J., Hanson, C. S., Chapman, J. R. \u003cem\u003eet al.\u003c/em\u003e Perspectives of older kidney transplant recipients on kidney transplantation. \u003cem\u003eClin. J. Am. Soc. Nephrol.\u003c/em\u003e\u003cstrong\u003e12\u003c/strong\u003e, 443\u0026ndash;453 (2017).\u003c/li\u003e\n\u003cli\u003eBunnik, E. M. Ethics of allocation of donor organs. \u003cem\u003eCurr. Opin. Organ Transplant.\u003c/em\u003e\u003cstrong\u003e28\u003c/strong\u003e, 192\u0026ndash;196 (2023).\u003c/li\u003e\n\u003cli\u003eGutmann, T. \u0026amp; Land, W. The ethics of organ allocation: the state of debate. \u003cem\u003eTransplant. Rev. (Orlando)\u003c/em\u003e\u003cstrong\u003e11\u003c/strong\u003e, 191\u0026ndash;207 (1997).\u003c/li\u003e\n\u003cli\u003eConcato, J., Shah, N. \u0026amp; Horwitz, R. I. Randomized, controlled trials, observational studies, and the hierarchy of research designs. \u003cem\u003eN. Engl. J. Med.\u003c/em\u003e\u003cstrong\u003e342\u003c/strong\u003e, 1887\u0026ndash;1892 (2000).\u003c/li\u003e\n\u003cli\u003eHalloran, P. F., Melk, A. \u0026amp; Barth, C. Rethinking chronic allograft nephropathy: the concept of accelerated senescence. \u003cem\u003eJ. Am. Soc. Nephrol.\u003c/em\u003e\u003cstrong\u003e10\u003c/strong\u003e, 167\u0026ndash;181 (1999).\u003c/li\u003e\n\u003cli\u003eMatsuo, S. \u003cem\u003eet al.\u003c/em\u003e Revised equations for estimated GFR from serum creatinine in Japan. \u003cem\u003eAm. J. Kidney Dis.\u003c/em\u003e\u003cstrong\u003e53\u003c/strong\u003e, 982\u0026ndash;992 (2009).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Living kidney donation, Older adult donors, Graft survival, Age matching, Propensity score matching","lastPublishedDoi":"10.21203/rs.3.rs-7818024/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7818024/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe persistent organ shortage has led to the consideration of \"marginal\" donors, including those of advanced age, but the outcomes of using living kidney donors aged 70 years or older remain debated. This multicenter retrospective cohort study aimed to evaluate the propriety of kidney donation from older adult donors by analyzing the association between transplant outcomes and recipient age. Using data from 633 adult living-donor kidney transplants, we compared an elderly donor group (age ≥70 years, n=75) with a non-elderly donor group (age \u0026lt;70 years, n=558). After 1:1 propensity score matching, the elderly donor group showed significantly lower death-censored graft survival. However, this disadvantage disappeared entirely in recipients aged 50 years or older, who exhibited comparable death-censored graft survival to those with non-elderly donors (\u003cem\u003ep\u003c/em\u003e=0.743). In contrast, recipients younger than 50 years who received grafts from elderly donors had markedly inferior death-censored graft survival (\u003cem\u003ep\u003c/em\u003e=0.008). In conclusion, using living kidney donors aged ≥70 years is a viable strategy to expand the donor pool, but its success is influenced by recipient age. These results support an age-sensitive approach in counseling and decision-making for kidney transplantation.\u003c/p\u003e","manuscriptTitle":"Clinical Outcomes of Living Kidney Transplantation from Older Adult Donors Aged 70 Years and Older: A Multicenter Study of Seven Kidney Transplantation Centers in Japan","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-03 17:43:36","doi":"10.21203/rs.3.rs-7818024/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-11-21T11:33:14+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-20T20:14:07+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-13T07:52:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"73379423649131830059674091171226591861","date":"2025-11-02T08:27:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"337236594838707001252836538415932622299","date":"2025-11-01T19:22:14+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-22T07:15:42+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-22T06:54:21+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-10-17T12:50:11+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-15T14:46:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-10-15T14:42:06+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3333c151-eb34-4c15-848f-cf9f8174d1eb","owner":[],"postedDate":"November 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":57287075,"name":"Health sciences/Health care"},{"id":57287076,"name":"Health sciences/Medical research"},{"id":57287077,"name":"Health sciences/Nephrology"}],"tags":[],"updatedAt":"2025-12-22T16:02:30+00:00","versionOfRecord":{"articleIdentity":"rs-7818024","link":"https://doi.org/10.1038/s41598-025-32558-x","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2025-12-18 15:58:05","publishedOnDateReadable":"December 18th, 2025"},"versionCreatedAt":"2025-11-03 17:43:36","video":"","vorDoi":"10.1038/s41598-025-32558-x","vorDoiUrl":"https://doi.org/10.1038/s41598-025-32558-x","workflowStages":[]},"version":"v1","identity":"rs-7818024","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7818024","identity":"rs-7818024","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}