Effect of Protein-Restricted Diet on Nitrogen Balance and Residual Renal Function in Peritoneal Dialysis (PD) Patients

Shanghai Jiao Tong University School of Medicine

Status: Completed

Conditions: Chronic Kidney Disease; Peritoneal Dialysis

Treatments: Dietary Supplement: diets contained different levels of protein

Study type: Interventional

Funder types: Other

Identifiers

NCT00633646

05PJ14057(Shanghai, China)

Details and patient eligibility

About

Current therapy recommendations suggest a low protein diet to preserve residual renal function (RRF) before the start of dialysis, but a higher protein intake during dialysis to prevent protein-energy wasting (PEW). We conducted a randomized trial to test whether low protein intake also during treatment with peritoneal dialysis (PD) would be safe and associated with a preserved RRF.

Full description

Dietary protein is the major source of nitrogen excreted as urea by the kidney, and a decreased protein intake has been associated with a retardation of kidney function loss in non-dialysis chronic kidney disease (CKD) patients. While a low protein diet is recommended to end-stage renal disease (ESRD) patients before the start of dialysis to preserve residual renal function(RRF), current therapy recommendations in dialysis are for a normal protein intake of no less than 1.2 g of protein/kg ideal body weight (IBW)/day to prevent protein-energy wasting (PEW).

We hypothesized that a lower protein intake would be safe and able to slow the loss of RRF also in dialysis patients and conducted two prospective, randomized trials involving a total of 94 peritoneal dialysis (PD) patients to test our hypothesis.

Enrollment: 94 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• age 18-80 years
• stable peritoneal dialysis since at least 1 month
• with renal function

Exclusion criteria

• a high probability (assessed by the recruiting physician) of receiving a kidney transplant within one year
• overt infection within the last month
• poor compliance in previous dietary prescriptions or irregular check-ups
• persistent anorexia, vomiting or diarrhea within the last month
• a CRP of more than 30 mg/dL
• presence of wasting diseases such as cancer or tuberculosis

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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94 participants in 3 patient groups

1

Active Comparator group

Description:

low protein diet

Treatment:

Dietary Supplement: diets contained different levels of protein

2

Active Comparator group

Description:

low protein diet with keto acids

Treatment:

Dietary Supplement: diets contained different levels of protein

3

Active Comparator group

Description:

high protein diet

Treatment:

Dietary Supplement: diets contained different levels of protein