Very Low Protein Diet and Renal Death in Chronic Kidney Disease (CKD)-ERIKA Study

The prevalence of chronic dialysis patients is increasing worldwide because of the rising incidence of end stage renal disease, it is burdened by high cardiovascular risk, it is associated with a very high morbidity and mortality and it determines enormous costs for the community. The improvement in the management of metabolic and cardiovascular complication associated to chronic kidney disease (CKD) since the early stages of the disease becomes mandatory in order to delay the start of dialysis and to ameliorate the whole patient outcome. Dietary protein restriction represents a basic therapeutic approach in CKD, by reducing the accumulation of nitrogen catabolic substances, the phosphorus retention and the consequent hyperparathyroidism, the metabolic acidosis, the salt intake and the consequent hypertension, the proteinuria, and by improving the anemia and the glycemic tolerance, but the effects of the low protein diet on renal failure progression rate have not been definitely demonstrated. Dietary effective reduction of just 0.2 g/kg/day of proteins is effective in ameliorating blood urea nitrogen, metabolic acidosis and hyperphosphoremia, and the very low protein diet (VLPD) allows a further improving of the metabolic control of uremia, it is safe, not affecting the nutritional status, and it is cost saving. VLPD has been suggested to delay the start of renal replacement therapy with respect to standard low protein diet, by mean of either secondary analysis of clinical trials or retrospective analysis. Large randomized clinical trials (RCT) on this issue lack, and the effect of VLPD on renal death remain to be addressed. As well, information on patients' compliance to VLPD prescription and on the impact of VLPD on the quality of life are needed. Finally, also the effects of VLPD on both cardiovascular risk factors and mortality remain to be completely evaluated. The primary aim of this study is to evaluate, by mean of a RCT, the effect of the very low protein diet on the renal death in renal patients affected by chronic renal insufficiency of moderate to advanced degree (CKD stages 4 and 5). Secondary aims are to evaluate the effect of VLPD on cardiovascular risk factors, morbidity and mortality, the adherence to VLPD, and the relationship between VLPD and quality of life.