Biochemical parameters, nutritional status and efficiency of dialysis in CAPD and CCPD patients

Several studies indicate that small solute transport is influenced by peritoneal dialysate volume and dwell time. This study focuses on the clinical impact of peritoneal dialysis modality, continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD).

We studied 18 patients on CAPD and 11 on CCPD for 18 months and assessed biochemical parameters, nutritional status and efficiency of dialysis at 6-month intervals.

Four-hour D/P urea and creatinine ratios were similar in both CAPD and CCPD patients. However, 24-hour D/P urea and creatinine ratios were significantly higher in CAPD than in CCPD patients (0.9 +/- 0.1 vs. 0.8 +/- 0.2 and 0.8 +/- 0.1 vs. 0.6 +/- 0.2, p < 0.05 and p < 0.01, respectively). The dialysate urea nitrogen concentration was significantly different between the two groups (65 +/- 14 mg/dl in CAPD, 48 +/- 13 mg/dl in CCPD; p < 0.05). Total weekly Kt/V and total weekly creatinine clearance were not significantly different between CAPD and CCPD patients at 18 months (1.6 +/- 0.4 vs. 1.7 +/- 0.3 and 52 +/- 21 vs. 50 +/- 12 liters, respectively). Two-way ANOVA with a post-hoc Bonferroni-Dunn test showed serum potassium concentration was significantly lower in CCPD patients at 18 months (3.8 +/- 0.5 mEq/l, p < 0.05), and significant increases in triglyceride levels in the CAPD groups by 18 months (301 +/- 286 mg/dl, p < 0.05).

This study demonstrates that the mean serum triglyceride level increases in CAPD patients over time, and the mean serum potassium concentration decreases in CCPD patients at 18 months. Dialysis adequacy and nutritional status are not significantly different between the two peritoneal dialysis modalities, CAPD and CCPD. We suggest the peritoneal dialysis prescription for CAPD or CCPD with respect to volume and frequency of exchanges be individualized to achieve adequate of therapy.