The National Kidney Foundation K/DOQI Clinical Practice Guidelines for Dietary Protein Intake for Chronic Dialysis Patients

This paper discusses two of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (K/DOQI) clinical practice guidelines for nutrition in chronic renal failure. These are the guidelines that recommend a dietary protein intake of 1.2 g protein/kg body weight/day for clinically stable maintenance hemodialysis (MHD) patients (Guideline 15) and 1.2 to 1.3 g protein/kg/day for clinically stable chronic peritoneal dialysis (CPD) patients (Guideline 16). These recommended protein intakes are greater than the usually ingested protein intakes of MHD and CPD patients and are also greater than the recommended protein intakes for healthy, nonpregnant, nonlactating adults. The possible mechanisms that engender these increased protein needs include (1) the substantial quantity of amino acids, peptides, and proteins removed by the dialysis procedure and (2) the protein catabolic or antianabolic state caused by the uremic milieu, the inflammatory state, the oxidative and carbonyl stress, and the bioincompatible dialysis materials to which MHD and CPD patients are exposed. There are a number of nitrogen balance studies that have been performed to identify the dietary protein needs of MHD and CPD patents. The results of this research as well as some of the methodological limitations of these studies are reviewed. The concepts of the average dietary protein intake required to maintain protein balance in MHD or CPD patients and the safe protein intake that will maintain protein balance in virtually all MHD and CPD patients are discussed.