Timing of Kidney Replacement Therapy among Children and Young Adults

Trends in Timing of Preemptive Kidney Transplantation and Association with Allograft and Survival Outcomes in Children

Key Points

Preemptive kidney transplant is occurring at higher levels of eGFR in US children over time. Higher level of eGFR at the time of transplant is not associated with patient or allograft survival. Implications of the observed trend of performing preemptive kidney transplant at higher eGFR on the long-term health of children deserve further study.

Background

There has been a recent trend toward starting dialysis at higher eGFRs in children, with no identified survival benefits. We aimed to determine whether there are similar trends in the timing of preemptive kidney transplant and whether higher eGFR (≥15 ml/min per 1.73 m2) at preemptive kidney transplant was associated with clinical outcomes among US children.

Methods

We performed a retrospective cohort study of 1514 children in the United States Renal Data System who received a preemptive kidney transplant between 2006 and 2019. In primary analysis, we examined the association between calendar year and eGFR (ml/min per 1.73 m2) at the time of preemptive kidney transplant, categorized as higher (eGFR ≥15) versus lower (eGFR <15) using logistic regressions. The relationship between eGFR at preemptive kidney transplant and graft failure or death was assessed using Cox proportional hazards and Fine–Gray models.

Results

We found a temporal trend in eGFR at preemptive kidney transplant in children; every 5-year increase in calendar period was associated with 55% higher odds (95% confidence interval, 1.35 to 1.79) of receiving a preemptive kidney transplant at higher eGFR. There was no association between preemptive kidney transplant at higher (versus lower) eGFR and risk of allograft failure or death (hazard ratio, 1.12; 95% confidence interval, 0.87 to 1.43) over a median follow-up of 5.7 years.

Conclusions

There has been a trend toward preemptive kidney transplant at higher eGFR over time in children. Receipt of a preemptive kidney transplant at higher eGFR was not associated with allograft or patient survival. Implications of these trends deserve further study.

Push toward pre-emptive kidney transplantation - for sure?

Pre-emptive kidney transplantation (PKT) has long been considered the optimal treatment for patients with end-stage chronic kidney disease (CKD) seeking the most favourable long-term outcomes. However, the significant growth in transplant procedures over recent decades has led to a notable increase in wait-listed patients and a disproportionate demand for donor organs. This situation necessitates a re-evaluation of transplantation timing and the establishment of rational indications from both societal and clinical perspectives. An increasing number of retrospective analyses have challenged the universal benefit of PKT, suggesting that premature indications for living or deceased donor PKT may not always yield superior hard outcomes compared with non-PKT approaches. Conventional predictive models have shown limitations in accurately assessing risks for certain subpopulations, potentially leading to significant disparities among wait-listed patients. To address these challenges, we propose the following considerations. Prediction models should not only optimize the distribution of our limited donor resources, but should also illuminate foreseeable risks associated with a potentially 'unsuccessful' PKT. Therefore, this article seeks to underscore the necessity for further discourse on the smouldering concept of when and for whom living or deceased donor PKT should be considered. Is it universally beneficial, or should the clinical paradigm be re-evaluated? In the endeavour to attain superior post-PKT survival outcomes compared with non-PKT or conservative treatment, it seems critical to acknowledge that other treatments may provide more favourable results for certain individuals. This introduces the intricate task of effectively navigating the complexities associated with 'too early' or 'unsuccessful' PKT.

Timing and Modality of Kidney Replacement Therapy in Children and Adolescents

Introduction

The choice and timing of kidney replacement therapy (KRT) is influenced by clinical factors, laboratory features, feasibility issues, family preferences, and clinicians' attitudes. We analyzed the factors associated with KRT modality and timing in a multicenter, multinational prospective pediatric cohort study.

Methods

A total of 695 pediatric patients with chronic kidney disease (CKD) enrolled into the Cardiovascular Comorbidity in Children with CKD (4C) study at age 6 to 17 years with estimated glomerular filtration rate (eGFR) of 10 to 60 ml/min per 1.73 m2 were investigated. Competing risk regression was performed to identify factors associated with initiation of dialysis or preemptive transplantation (Tx), including primary renal diagnosis, demographics, anthropometrics, and laboratory parameters.

Results

During the 8-year observation period, 342 patients (49%) started KRT. Of these, 200 patients started dialysis, whereas 142 patients underwent preemptive Tx. A lower eGFR at enrolment (Hazard ratio [HR]: 0.76 [95% confidence interval: 0.74-0.78]), a steeper eGFR slope (HR: 0.90 [0.85-0.95], and a higher systolic blood pressure SD score (SDS) (HR: 2.07 [1.49-2.87]) increased the likelihood of KRT initiation. Patients with glomerulopathies were more likely to start dialysis than children with congenital anomalies of the kidneys and urinary tracts (CAKUT) (HR: 3.81 [2.52-5.76]). Lower body mass index (BMI) SDS (HR: 0.73 [0.6-0.89]) and lower hemoglobin (HR: 0.8 [0.72-0.9]) were associated with higher likelihood of dialysis. A significant center effect was observed, accounting for 6.8% (dialysis) to 8.7% (preemptive Tx) of explained variation.

Conclusion

The timing and choice of KRT in pediatric patients is influenced by the rate of kidney function loss, the underlying kidney disease, nutritional status, blood pressure, anemia and center-specific factors.