• Intervention
    What are the protein requirements to minimize disease progression while maintaining adequate nutrition status in adult non-dialyzed patients with diabetic nephropathy?
    • Conclusion

       

      • Meta-analysis results of four RCTs and two non-RCTs published before 1996 suggest that patients with diabetic nephropathy who were on dietary protein restriction diets had significantly reduced rate of GFR decline compared to those on usual protein diets. However, seven later RCTs involving about four times more patients than the meta-analysis show conflicting findings. Specifically, more recent RCTs (published after 1999) show that low protein diet (0.6g to 0.89g per kg per day) without ketoacid supplementation for up to two years did not significantly alter GFR decline when compared to subjects' usual protein diet (1.0g to 1.4g per kg per day), regardless of the stage of CKD or type of diabetes among patients with diabetic nephropathy. The reported effects on proteinuria or microalbuminuria were inconsistent across studies. Nutrition status can be maintained with either a low protein or a usual protein diet.
      • Data on the effects of protein-restriction diets on clinical outcomes of renal function are limited. One positive RCT shows that the relative risk of progression to Stage 5 chronic kidney disease (CKD) or overall mortality was significantly reduced [0.23 (95% CI 0.07, 0.72), P=0.01] for type 1 diabetes patients assigned to a low-protein diet (0.89g per kg per day), compared to those assigned to a free-protein diet.
      • Results from one RCT suggests that ketoacid supplementation may be needed to preserve renal function among patients who are on a very-low protein diet (0.3g per kg per day).

       

    • Grade: II
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What are the protein requirements to minimize disease progression while maintaining adequate nutrition status in adult non-dialyzed patients with kidney transplant?
    • Conclusion

      Results from one study of kidney transplant patients with declined graft function (GFR less than 60ml per minute per 1.73m2) suggest that a low-protein diet (0.55g per kg per day) can reduce proteinuria, compared to high-protein diet (2.0g per kg per day).

    • Grade: III
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.
    What are the protein requirements to minimize disease progression while maintaining adequate nutrition status in adult non-dialyzed, non-diabetic patients with chronic kidney disease?
    • Conclusion
      • Meta-analysis results of nine RCTs published before 1999 suggest that non-diabetic CKD patients who were on dietary protein restriction diets had significantly reduced risk of renal failure (all-cause death or start of dialysis) and significantly reduced rate of GFR decline compared to those on usual protein diets. RCTs and other uncontrolled trials published after the meta-analysis report consistent findings. These RCTs show that protein-restricted diets, inclusive of low and very-low protein diets, ranging from 0.3g to 0.7g per kg BW per day with total energy intake of 23 to 35kcal per kilograms body weight can slow GFR decline and maintain stable nutrition status in adult non-diabetic patients with chronic kidney disease (CKD).
      • International studies reported additional keto acid analogs, and vitamin or mineral supplementation are needed to maintain adequate nutrition status for patients with CKD who consume a very-low protein diet (0.3 to 0.5g per kg BW per day)
      • Limited evidence suggest that adding keto acid supplements is better than amino acid supplements to slow GFR decline among non-diabetic CKD patients who received a very low-protein diet (0.3g per kg BW per day). 
         
    • Grade: I
      • Grade I means there is Good/Strong evidence supporting the statement;
      • Grade II is Fair;
      • Grade III is Limited/Weak;
      • Grade IV is Expert Opinion Only;
      • Grade V is Not Assignable.
      • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
      • Moderate (B) means we are moderately confident in the effect estimate;
      • Low (C) means our confidence in the effect estimate is limited;
      • Very Low (D) means we have very little confidence in the effect estimate.
      • Ungraded means a grade is not assignable.