The Kidney Failure Risk Equation for Prediction of Allograft Loss in Kidney Transplant Recipients

Abstract

Rationale & Objective The Kidney Failure Risk Equation (KFRE) is a simple widely validated prediction model using age, sex, estimated glomerular filtration rate, and urinary albumin-creatinine ratio to predict the risk for end-stage kidney disease. Data are limited for its applicability to kidney transplant recipients. Study Design Validation study of the KFRE as a post hoc analysis of the Folic Acid for Vascular Outcomes Reduction in Transplantation (FAVORIT) Trial. Setting & Participants Adult kidney transplant recipients with functioning kidney allografts at least 6 months posttransplantation from 30 centers in the United States, Canada, and Brazil. Participants with estimated glomerular filtration rates < 60 mL/min/1.73 m 2 at study entry were included. Predictor 2- and 5-year kidney failure risk predicted by the KFRE using variables at study entry. Outcome Graft loss, defined by initiation of dialysis. Analytical Approach Discrimination of the KFRE was assessed using C statistics; calibration was assessed by plotting predicted risk against observed cumulative incidence of graft loss. Results 2,889 participants were included. Within 2 years, 98 participants developed graft loss, 107 participants died with a functioning graft, and 129 participants were lost to follow-up, and by 5 years, 252 had developed graft loss, 265 died with a functioning graft, and 1,543 were lost to follow-up. The KFRE demonstrated accurate calibration and discrimination (C statistic, 0.85 [95% CI, 0.81-0.88] at 2 years and 0.81 [95% CI, 0.78-0.84] at 5 years); performance was similar regardless of donor type (living vs deceased) and graft vintage, with the noted exception of poorer calibration for graft vintage less than 2 years. Limitations Unavailable cause of graft loss. Conclusions The KFRE accurately predicted the risk for graft loss among adult kidney transplant recipients with graft vintage longer than 2 years and may be a useful prognostic tool for nephrologists caring for kidney transplant recipients.

Predialysis Vascular Access Placement and Catheter Use at Hemodialysis Initiation

“…A recent study found that among patients with an eGFR <15 ml/min per 1.73 m 2 , the eGFR and KFR equation had a similar predictive value for estimating time to kidney failure. 26…”

Access to kidney transplantation among pediatric candidates with prior solid organ transplants in the United States

“…The reasons for low rates of preemptive listings among these candidates and others with high priority for kidney transplants are not totally clear and warrant further study, although demographic and socioeconomic factors are likely contirbutors 21,22 . Additional strategies to improve early wait‐listing might include refitting pediatric kidney failure risk equations to improve their performance in organ transplant recipients, as has been performed in adults, to help providers identify which prior transplant recipients have a risk of needing a transplant in the near future 23–27 . Alternatively, it is possible that some centers may intentionally delay consideration for a retransplant for select candidates with prior nonadherence until concerns for future adherence are addressed, but we are unable to test this hypothesis with available data.…”

Albuminuria, proteinuria, and dipsticks: novel relationships and utility in risk prediction

“…Calibration of the model was also good. Finally, Chu et al examined a cohort of 2889 posttransplant patients more than 6 months posttransplant, provided their eGFR was less than 60 ml/min/1.73 m 2 [22 ▪ ]. Here, the four-variable KFRE performed well at 2 and 5 years, with C-statistics of 0.85 (95% CI: 0.81–0.88) and 0.81 (95% CI: 0.78–0.84).…”