Kidney-transplanted Adolescents—Nonadherence and Graft Outcomes During the Transition Phase: A Nationwide Analysis, 2000–2020

The transition from pediatric to young adult care is a vulnerable period for the renal transplant patient. We aimed to identify medication nonadherence (noninitiation, nonimplementation, and nonpersistence) and graft loss rates among adolescents and young adults and elucidate the influence of the transition phase on transplant outcomes. METHODS. A retrospective nationwide cohort analysis of all renal transplantations in Norway from 2000 to 2020 was performed. Data were retrieved from the Norwegian Renal Registry, and adherence data from hospital charts. Patients transplanted aged <50 y, with functioning graft at 6 mo, were included. Recipients transplanted aged <26 y were compared with recipients transplanted aged 26–50 y. Graft loss, acute rejection, and development of de novo donor-specific antibodies were assessed in relation to the transition phase, defined as 14–26 y. RESULTS. Data from 1830 kidney recipients were included: 371 (20%) transplanted <26 y (64% male, 68% living donor) versus 1459 transplanted 26–50 y (63% male, 44% living donor). There were 298 graft losses, 78 (21%) in the <26-y group versus 220 (15%) in the 26- to 50-y group. During the transition phase, 36 grafts were lost, 29 (81%) after transfer to the adult service. Medication nonadherence was the reason for 58% (21 of 36) of the losses during the transition phase, versus 12% (27 of 220) in the 26- to 50-y group (P < 0.001). The 5-y graft survival rate was 89% (95% confidence interval, 85%-92%) and 94% (92%-95%), respectively (P = 0.01). CONCLUSIONS. Nonadherence was verified as the main cause of kidney graft loss in the transition phase.