Outcomes in elderly kidney transplant recipients: a national multicentre study

Abstract

Background and Aims: Kidney transplantation is the preferred treatment modality for end-stage renal disease in all age groups. However, there is still a lack of data on transplant outcomes in the elderly population. This study aims to evaluate the long-term outcomes of elderly kidney transplant recipients compared with the younger population. Method: The study was a retrospective, multicentre cohort study and included patients aged 50 years and older who underwent kidney transplantation between 2015 and 2020. Patients with a follow-up period of less than six months were excluded. The elderly group was defined as patients aged 60 years and older, and patients aged 50–59 years were defined as the control group. The study’s endpoints were death, death with a functioning graft, allograft loss, and allograft rejection, and the defined endpoints were compared between the groups. Results: The study included 1305 patients. The median age of the patients was 56 years (50–76), and 39.4% of the participants were female. The median follow-up period was 61.5 (6–113) months in the elderly group and 65.0 (6–115) months in the control group, respectively (P = 0.007). With respect to living kidney transplantation, 79.4% (no. = 313) of the elderly group and 70.4% (no. = 641) of the control group had a living related transplantation (P = 0.001). In the elderly group (n = 396),the prevalence of diabetic nephropathy, deceased donor use, ischaemic heart disease, and induction therapy with basiliximab was significantly higher compared to the control group (P = 0.002, P = 0.001, P = 0.007, P = 0.01, respectively). In terms of the induction agents, ATLG was used in 337 (91.3%) and 772 (95.2%) patients in the elderly and control group; respectively(P = 0.01). The frequency of acute rejection after the first year was lower in the elderly group compared to the control group (P = 0.040). The mortality rate was 77 (21.9%) in the elderly group and 116 (14.4%) in the control group. In addition, graft loss occurred in 16 (4.6%) patients in the elderly group and 53 (6.7%) patients in the control group. Kaplan-Meier analyses showed that the frequency of hospitalization, all-cause mortality, and death with a functioning graft were significantly higher in the elderly group than in the control group (P = 0.029, P = 0.002, P = 0.04, respectively). According to Cox regression analysis, the risk of death in the elderly group was 1.65 times higher than in the control group (95% CI: 1.19–2.30, P = 0.002). In addition, the risk of death with a functioning graft increased 1.04-fold for each year increase after the age of 50 years (95% CI:1.013–1.07, P = 0.003). Conclusion: Older kidney recipients had increased rates of death with a functioning graft, probably due to an increased prevalence of ischaemic heart disease, but decreased incidence of graft loss and acute rejection after the first year. These findings suggest that the elderly population should be monitored more closely for cardiovascular disease and that there may be potential benefit in limiting the use of cardiotoxic immunosuppressive agents, particularly in high-risk patients within the first year.