Efficacy of the 6-point Diet (PIS)

Effects of the 6-point Diet on the Metabolic Control, the Compliance and the Nutritional Status of CKD Patients Stage 3b-5

The dietary restriction of proteins and sodium is a cornerstone in the treatment of chronic kidney disease (CKD) and of its metabolic consequences. Dietary adjustments in CKD are complex and the patients' compliance is very low. A dietary interview method is a validated instrument to evaluate the patients' compliance; however, it the presence of a dedicated dietitians. 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.

Study Overview

• Status: Completed
• Conditions: Chronic Kidney Disease
• Intervention / Treatment: Dietary supplement: Low protein diet; Dietary supplement: Six point diet

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Actual): 54
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Naples, Italy, 80129
    • federico II university, department of nephrology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Low protein diet; The patients of this group received a classical low protein diet (LPD),according to their desired body weight (DBW), obtained by multiplying the squared value of the height times a reference body mass index (BMI) value of 23. LPD were individually prepared and explained to the patients by a dedicated dietician and contained at least 30 kcal/kg/day (25 in overweight patients), with a dietary sodium intake restricted to 2.5 g/day.	Dietary supplement: Low protein diet; Classical low-protein diet prescribed according to the patients' desired body weight (DBW), obtained by multiplying the squared value of the height times a reference BMI value of 23. These diets contained at least 30 kcal/kg/day (25 in overweight patients), with a dietary sodium intake restricted to 2.5 g/day.
Experimental: Six point diet; These patients were assigned to receive the 6-points-diet, and were given by the Nephrologist the list of six items indicating how to modify their dietary habits; all the items were thoroughly explained and discussed with the patients	Dietary supplement: Six point diet; The 6-point diet is a list of six items indicating how to modify their dietary habits: Do not add salt at table and for cooking;; Food to avoid: any kind of salami, sausages, cheese and dairy products or canned food;; Replace noodle or bread with special no-protein food;; The second course (meat, fish and eggs) are allowed once a day in the usual quantity;; 4-5 servings/day of fruits or vegetables are suggested;; Once or twice a week the main course may be of "normal" noodle with legumes instead of the second course, with fruit and vegetables.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect on renal disease progression	Evaluation of modification of GFR and proteinuria	6 months
Effect on metabolic control	Evaluation of the modifications of serum urea nitrogen, sodium, potassium, phosphate, bicarbonate, parathormone , urinary urea nitrogen, phosphate, potassium, sodium, protein and phosphate intake	6 months
Effect on nutritional status	Evaluation of modifications of total protein, albumin, C-reactive protein, body weight, BMI	6 months
Effect on patients'compliance to the dietetic therapy	The compliance was defined by a constant protein intake between 0.7 and 0.9 g/kg B.W. throughout the study	6 months

Collaborators and Investigators

• Sponsor: Federico II University
• Investigators: Principal Investigator: eleonora riccio, md, Federico II University

Publications and helpful links

General Publications

• Pisani A, Riccio E, Bellizzi V, Caputo DL, Mozzillo G, Amato M, Andreucci M, Cianciaruso B, Sabbatini M. 6-tips diet: a simplified dietary approach in patients with chronic renal disease. A clinical randomized trial. Clin Exp Nephrol. 2016 Jun;20(3):433-42. doi: 10.1007/s10157-015-1172-5. Epub 2015 Oct 9.

Study record dates

Study Major Dates

• Study Start: March 1, 2010
• Primary Completion (Actual): November 1, 2012
• Study Completion (Actual): December 1, 2012

Study Registration Dates

• First Submitted: May 24, 2013
• First Submitted That Met QC Criteria: May 30, 2013
• First Posted (Estimate): May 31, 2013

Study Record Updates

• Last Update Posted (Estimate): May 31, 2013
• Last Update Submitted That Met QC Criteria: May 30, 2013
• Last Verified: December 1, 2012

More Information

Terms related to this study

• Keywords: Chronic kidney disease; Low protein diet; CKD stage 3b-5
• Additional Relevant MeSH Terms: Urologic Diseases; Renal Insufficiency; Kidney Diseases; Renal Insufficiency, Chronic
• Other Study ID Numbers: PIS; Carlo Romano (Other Identifier: Ethic commettee)