Multicenter International Observational Study to Identify eGFR Trajectories and Their Determinants, and to Build a Multidimensional Prediction System to Predict the Probabilities of Belonging to eGFR Trajectories

The gold standard for characterizing chronic kidney disease (CKD) is the glomerular filtration rate (GFR), which is commonly estimated in both native and transplanted kidneys for patient monitoring and therapeutic management and ultimately guides decision-making about whether a patient needs renal replacement therapy. In particular, the National Kidney Foundation has defined CKD stages according to estimated GFR (eGFR) values and in several studies, the eGFR slope or change has been found to be strongly associated with end stage renal disease (ESRD).

However, little is known about the heterogeneity of eGFR evolution in time - i.e. eGFR trajectories - and the related progression to ESRD and death. To date, no studies have investigated eGFR trajectories in diversified cohorts and populations worldwide, although this approach could provide a better understanding of CKD evolution and hence improve risk stratification. In addition, determinants of eGFR trajectories remain poorly described.

An unsupervised approach could allow examining eGFR trajectories over time and could lead to the identification of patient groups according to the probability of the progression of their kidney disease.

Therefore, this study aims:

1. To identify the long-term eGFR trajectories after kidney transplantation using latent class mixed models;
2. To identify the clinical, immunological, histological and functional determinants of the eGFR trajectories using multinomial regressions;
3. To investigate the associations of the eGFR trajectories with the progression to ESRD and death.

Based on the results, the investigators will provide an easily accessible tool to calculate personalized probabilities of belonging to eGFR trajectories after kidney transplantation, by using datasets from prospective cohorts and post hoc analysis of randomized control trial datasets.