Treatment of advanced renal failure: low-protein diets or timely initiation of dialysis?

Until 1996, no guidelines existed for the initiation of dialysis in patients with progressive renal failure. The publication of the National Kidney Foundation-Dialysis Outcome Quality Initiative guidelines has generated a debate on the management of advanced renal failure and the role of low-protein diets (LPDs). We performed a review of the literature to identify articles on the initiation of dialysis and LPDs, particularly those since 1996. Delayed referral of patients is widespread in both the United States and Europe, and almost 25% of patients are started on dialysis at a glomerular filtration rate (GFR) of <5 mL/min/1.73 m2. There is a high prevalence of malnutrition at the time of first dialysis, which progressively improves upon initiation of dialysis. There is no evidence regarding the efficacy or safety of LPDs in nondiabetic patients younger than 70 years old [approximately 40% of U.S. incident end-stage renal disease (ESRD) patients] and in diabetics with GFR <25 mL/min/1.73 m2 (>40% of incident U.S. ESRD). In nondiabetics who are younger than 70 years old, adherence to LPD for four to five years can be estimated to result in a delay in dialysis by 6 to 11 months. However, suboptimal energy intake is widespread in advanced renal failure, which declines further upon institution of LPD. Even nutritionally sound patients develop subclinical nutritional decline despite intense counseling. There are no data on the efficacy or safety of LPD in subgroups that constitute approximately 80% of incident ESRD patients. Concerns still exist regarding their nutritional safety in the remainder. Initiation of dialysis results in improved nutritional status and should be considered in a timely fashion.