Clinical Courses of Graft Failure Caused by Chronic Allograft Dysfunction in Kidney Transplantation.

BACKGROUND: Chronic allograft dysfunction (CAD) is a main cause of graft failure in kidney transplantation. METHODS: We retrospectively analyzed 279 kidney transplant recipients who survived with a functioning graft for at least 2 years. CAD was defined as chronic graft deterioration, excluding other specific causes. We defined the pattern of decline in estimated glomerular filtration rate (eGFR), as follows: (1) "plateau" was defined as decline in eGFR ≤2 mL/min/1.73 m2/year; "long plateaus" were those lasting more than 5 years; (2) "rapid decline" was a decrease in eGFR ≥20 mL/min/1.73 m2/year. Patients diagnosed with CAD were categorized according to the occurrence of rapid decline and/or long plateau as follows: group 1, neither rapid decline nor long plateau; group 2, rapid decline only; group 3, long plateau only; and group 4, both rapid decline and long plateau. RESULTS: From a total of 81 graft losses, 51 (63%) failed because of CAD, with a median of 9.4 years. Sixteen patients belonged to group 1, 14 to group 2, 12 to group 3, and nine to group 4. Mean graft survival times in the four groups were 7.7 ± 1.1, 6.1 ± 3.1, 16.2 ± 2.5, and 10.8 ± 3.6 years, respectively (P < .001). There were significant differences among groups in donor age, year of transplantation, mean eGFR at baseline, and acute rejection rate after transplantation. CONCLUSIONS: The results indicate that this cohort of kidney transplant recipients who had CAD comprised subgroups with different clinical courses.

Impact of recipient aging on kidney allograft in living donor transplantation.

BACKGROUND: The aging of recipients is becoming increasingly important in organ transplantation. PATIENTS AND METHODS: We analyzed outcomes in 215 consecutive adult kidney transplant recipients from living donors who underwent transplantation at our center between November 1988 and March 2012. The list of recipients was divided by age at transplantation into those aged 16 to 29 years (n = 61), 30 to 39 years (n = 69), 40 to 49 years (n = 33), 50 to 59 years (n = 29), and those 60 years or older (elderly group, n = 23). Cox proportional hazards analysis was used to calculate the relative risk (RR) of patient death and graft failure, with recipient age included as a continuous variable. RESULTS: Univariate analysis showed that recipient age did not significantly affect the risk of graft failure, either uncensored (RR = 1.01, P = .312) or censored for death (RR = 0.993, P = .587). Multivariate analysis, however, showed that recipient age was an independent risk factor for patient death (RR = 1.053, P = .024). The patient survival rate was the poorest in elderly group (87.0%, P = .036), whereas the both death uncensored and censored graft survival rates of this group were 78.1% and 91.3%, respectively, comparable to those of other age groups (P = .567 and P = .696). Mean estimated glomerular filtration rate (eGFR) 1 year after transplantation was lower in elderly groups than in other groups (46.1 ± 13.0 mL/min/1.73 m(2), P = .014). However, mean δeGFR, defined as the difference between pretransplantation eGFR of the donor and eGFR of the recipient 1 year post-transplantation, did not differ significantly among age groups. CONCLUSION: Recipient age did not affect allograft deterioration in living donor kidney transplantation, although it was an independent risk factor of recipient death.