Efficacy of the 6-point Diet

The dietary restriction of proteins and sodium is a cornerstone in the treatment of chronic kidney disease (CKD) and of its metabolic consequences. In fact, a reduced protein intake decreases load on remaining nephrons, reduces signs and symptoms of uraemia, lessens the accumulation of waste metabolic products and oxidant stress, improves insulin-resistance and lipid profile, ameliorates proteinuria, additives effects of angiotensin-converting-enzyme inhibitors, and decreases likelihood of patients death or delays initiation of dialysis by 40%.

Dietary adjustments in subjects with chronic renal failure are complex because multiple nutrient modifications are required and changes in lifestyle must be maintained for years. Furthermore, low-protein diet is considered tedious, unpalatable and difficult to achieve. This has an obvious negative influence on the quality of life of patients and makes their adherence to the new therapeutic prescriptions more difficult. In fact, the difficulty to reach patients' compliance is well known. There is ample evidence that poor adherence is considered a critical barrier to treatment success and remains one of the leading challenges to healthcare professionals. Few data are available in clinical practice concerning the patients' compliance to low protein diet. A dietary interview method is a validated instrument to evaluate the practice and routines related to the assessment of nutrient intake in nondialyzed CKD patients and to obtain the patients' compliance. However, the interview requires the presence of a dedicated dietitian and a lot of his time.

For these reasons, and because of the absence of dedicated dietitians in many nephrology centres, it is usual practice to give standard low protein diets to CKD patients not on dialysis.

Aim of this study was to verify if few simple tips were able to reduce protein, phosphate and sodium intake in patients with CKD, as compared to the practice of giving a low protein diet elaborated by a renal dietitian.

Inclusion criteria

• age >18 years
• a basal value of estimated GFR (eGFR) < 45 ml/min/1,73 m2, that had to remain stable during 3 consecutive controls (eGFR variability <15% along 1 month)

Exclusion criteria

• unstable renal function,
• inability to perform correct 24-hours urine collections,
• presence of malignancies,
• treatment with immunosuppressive drugs,
• pregnancy,
• congestive heart failure (NYHA class III-IV),
• proteinuria >3,5 g/24 hours