Definitions for the levels of evidence (I–IV) can be found at the end of the "Major Recommendations" field.
Guidelines
No recommendations possible based on Level I or II evidence
Suggestions for Clinical Care
(Suggestions are based on Level III and IV evidence)
- For patients with progressive chronic kidney disease (CKD), who receive a protein-restricted diet, the protein content should not be lower than 0.75 g per kg ideal body weight (IBW) per day. The protein should be of at least 50% high biological value. An energy intake of at least 35 kCal/kg IBW/day to minimise protein-energy malnutrition must accompany a low protein diet. (Level II evidence)
- CKD patients should not commence a lower protein diet until any plasma acidosis is corrected. (Level III evidence)
It is recommended 15% to 20% of daily energy intake is in the form of protein. Over 50% of this protein should be of high biological value (see the Appendix in the original guideline document).
Low protein diets may increase the risk of zinc, selenium, and some B vitamin (riboflavin, pyridoxine, B12) deficiencies.
It is important to appreciate that hypoalbuminaemia is not necessarily synonymous with malnutrition. Patients may have a low plasma albumin concentration due to decreased albumin synthesis or because they are acutely unwell or have evidence of an acute phase response, suggesting an underlying inflammatory (and therefore catabolic) process.
In some populations, the protein portion of the daily energy intake (DEI) exceeds 20% to 25% (some 2 g/kg/24 hours). Protein restriction diets below the level of 1.2 g/kg lean body weight/24 hours may be impracticable to implement.
Between 50% and 66% high biological protein content has been recommended or used (see Table 1 in the Appendix in the original guideline document). This recommendation is to ensure the limited protein taken is maximally utilised for its amino acid composition, and not for energy. It is imperative that adequate energy is consumed with the protein restriction diet to avoid protein-energy malnutrition (see Suggestions for Clinical Care in the "Energy intake in pre-dialysis patients" guideline).
Definitions:
Levels of Evidence
Level I: Evidence obtained from a systematic review of all relevant randomized controlled trials (RCTs)
Level II: Evidence obtained from at least one properly designed RCT
Level III: Evidence obtained from well-designed pseudo-randomized controlled trials (alternate allocation or some other method); comparative studies with concurrent controls and allocation not randomized, cohort studies, case-control studies, interrupted time series with a control group; comparative studies with historical control, two or more single arm studies, interrupted time series without a parallel control group
Level IV: Evidence obtained from case series, either post-test or pretest/post-test
