Effect of nonsupplemented low-protein diet on very late stage CRF

Background: There are few reports of the effect of a low-protein diet on very late-stage chronic renal failure (CRF), eg, serum creatinine level greater than 10 mg/dL (884 mumol/L). In this retrospective study, we examined the effects of a very low-protein diet in patients with very late-stage CRF. Methods: A very low-protein diet (0.25 to 0.54 g/kg body weight/d [0.39 +/- 0.01 g/kg body weight/d]) without supplementation of essential amino acids or keto analogues was administered to 76 patients with very late-stage CRF who had serum creatinine levels greater than 10 mg/dL (884 mumol/L). Twenty-one patients with the same serum creatinine level and protein intake of 0.55 to 1.2 g/kg body weight/d (0.68 +/- 0.03 g/kg body weight/) were observed in lieu of controls. Results: Blood urea nitrogen was significantly suppressed to 43.1 +/- 1.9 g/dL (15.4 +/- 0.7 mmol/L) in the low-protein group compared with 111.2 +/- 7.0 mg/dL (39.7 2.5 mmol/L; P < 0.001) in the control group. The rate of decline in glomerular filtration rate (creatinine clearance) was 36-fold slower with the low-protein diet (-7.1 +/- 1.0 versus -0.2 +/- 0.4 mL/mon, respectively; P < 0.001). Nutritional state in the low-protein group exceeded that of the control group. Consequently, the renal survival rate improved significantly (P < 0.0001). All patients in the control group were initiated on dialysis treatment within 6 months from a serum creatinine level of 10 mg/dL (884 μmol/L). Conversely, 58% of the low-protein group are still on predialysis treatment. Conclusion: A severe low-protein diet is effective not only in preventing deterioration in renal function, but also in maintaining nutritional state despite no supplementation of essential amino acids or keto analogues, even as serum creatinine level is more than 10 mg/dL.