Predictive factors of progression to chronic kidney disease stage 5 in a predialysis interdisciplinary programme

Background. The clinical course of chronic kidney disease (CKD) in children is heterogeneous and has not been fully established. The aim of this retrospective cohort study was to identify predictive factors associated with the progression of CKD among the children and adolescents admitted to a Predialysis Interdisciplinary Management Programme (PDIMP). Methods. We analysed the following variables at admission: age, gender, race, blood pressure, primary renal disease, Z-scores for weight and height, CKD stage and degree of proteinuria. Two time-dependent covariates were considered: hypertension and proteinuria. CKD stage 5 was assigned as a dependent variable. Time-fixed and time-dependent Cox regression analyses were applied to evaluate renal survival. Results. One hundred and seven patients with CKD stage 2-4 were followed up for a median time of 94 months. Fifty-seven patients (53.3%) progressed to CKD stage 5. After adjustment for time-fixed model, three baseline variables were found to be independent predictors of CKD stage 5: glomerular disease (hazard ratio, HR = 3.0, P = 0.015), CKD stage 4 (HR = 2.6, P = 0.001) and severe proteinuria (HR = 4.1, P = 0.006). After adjustment for the time-dependent model, three variables were found to be independent predictors of CKD stage 5: proteinuria as time-dependent covariate (HR = 1.9, P = 0.041), CKD stage 4 (HR = 2, P = 0.0086) and baseline serum albumin < 3.5 g/dl (HR = 2.6, P = 0.0015). Conclusions. Taking into account manageable factors, further prospective controlled studies are necessary to assess intervention measures in order to possibly modify the clinical course of CKD in children.