Dialysis adequacy in Chinese anuric peritoneal dialysis patients

We aimed in this study to explore how lower-protein diet would affect dialysis adequacy in anuric peritoneal dialysis (PD) patients.

Patients' demographic features were collected, namely age, gender, weight, height, underlying renal disease, and time on PD. Urea kinetic model was used to assess solute clearance. A consecutive 3-day dietary record was collected to evaluate dietary protein intake (DPI), and normalized protein nitrogen appearance (nPNA) was also calculated to reflect protein intake. Blood samples were collected to measure hemoglobin and biochemistry. Patient's nutritional status was assessed by biochemistry, handgrip strength, and subjective global assessment (SGA). Body fluid distribution was measured by body composition monitor.

Patients were 60.8 ± 14.92 years old, and the time on PD was 40.15 ± 22.90 months. Daily prescribed dialysis dose was 7,178 ± 1,326 mL. Kt/V was 1.6 ± 0.32. DPI was 0.8 ± 0.25 g/kg/day. nPNA was 0.9 ± 0.21 g/kg/day. Serum albumin was 39.42 ± 4.83 g/L. Prevalence of malnutrition (assessed by SGA) was 20.2 %. Serum phosphate and serum bicarbonate were 1.68 ± 0.47 and 27.16 ± 3.49 mmol/L, respectively. Systolic blood pressure and diastolic blood pressure were 123.4 ± 20.0 and 74.2 ± 12.6 mmHg, respectively. Patients with nPNA less than 0.6 had significantly lower serum albumin concentrations than the average, and patients with nPNA more than 1.2 g/kg/day had significantly higher levels of serum phosphate and serum urea than the average.

Our study suggested that anuric PD patients could achieve adequate dialysis even under lower solute clearance. And lower-protein diet contributed largely to adequate dialysis in these patients.