Effect of dietary protein restriction on prognosis in patients with diabetic nephropathy

Kidney Int. 2002 Jul;62(1):220-8. doi: 10.1046/j.1523-1755.2002.00421.x.


Background: Recent data suggest that dietary protein restriction improves survival and delays the progression to end-stage renal disease (ESRD) in non-diabetic nephropathies. The purpose of our study was to determine the effect of dietary protein restriction on survival and progression to ESRD in diabetic nephropathy.

Methods: A four-year prospective, controlled trial with concealed randomization was performed comparing the effects of a low-protein diet (0.6 g/kg/day) with a usual-protein diet. The study included 82 type 1 diabetic patients with progressive diabetic nephropathy [pre-study mean decline in glomerular filtration rate (GFR) 7.1 mL/min/year (95% CI, 5.8 to 8.5)]. The main outcome measures were decline in GFR and development of ESRD or death.

Results: During the follow-up period the usual-protein diet group consumed 1.02 g/kg/day (95% CI; 0.95 to 1.10) as compared with 0.89 (0.83 to 0.95) in the low-protein diet group (P = 0.005). The mean declines in GFR were 3.9 mL/min/year (2.7 to 5.2) in the usual-protein diet group and 3.8 (2.8 to 4.8) in the low-protein diet group. ESRD or death occurred in 27% of patients on a usual-protein diet as compared with 10% on a low-protein diet (log-rank test; P = 0.042). The relative risk of ESRD or death was 0.23 (0.07 to 0.72) for patients assigned to a low-protein diet, after an adjustment at baseline for the presence of cardiovascular disease (P = 0.01). Blood pressure and glycemic control were comparable in the two diet groups during the follow-up period.

Conclusion: Moderate dietary protein restriction improves prognosis in type 1 diabetic patients with progressive diabetic nephropathy in addition to the beneficial effect of antihypertensive treatment.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Diabetes Mellitus, Type 1 / complications*
  • Diabetic Nephropathies / blood
  • Diabetic Nephropathies / complications*
  • Diabetic Nephropathies / physiopathology
  • Diet, Protein-Restricted*
  • Female
  • Glomerular Filtration Rate
  • Glycated Hemoglobin / analysis
  • Humans
  • Kidney Failure, Chronic / etiology
  • Kidney Transplantation
  • Male
  • Middle Aged
  • Nutritional Status
  • Prognosis
  • Prospective Studies
  • Regression Analysis
  • Renal Dialysis


  • Glycated Hemoglobin A