Improvement in uremic symptoms after increasing daily dialysate volume in patients on chronic peritoneal dialysis...

Patients on peritoneal dialysis (PD) can develop uremic symptoms as their residual renal function declines. In this retrospective study, we assessed the effect of increasing the dose of dialysis in patients who developed uremic symptoms.

Patients on PD who had an increase in their dialysis dose due to either the appearance of uremic symptoms or to worsening biochemical parameters were included in this study. These patients had to have been on PD for at least 6 months before and after the increase in their dialysis dose. Patients whose dialysis dose was increased after the initial Adequest (done within 2-3 months of starting PD) findings or for reasons other than underdialysis were excluded from this study. The symptoms studied in 104 patients included fatigue, anorexia, insomnia, pruritus and nausea. The presence or absence of theses symptoms was evaluated before and after the increase in the dialysis volume. Several clinical and laboratory data including the adequacy results were compared before and after the increase in dialysis dose.

Patients were on PD for 24.6+/-16 months when dialysis dose was increased. Eighty-five (82%) of them were on continuous ambulatory peritoneal dialysis (CAPD) while the remaining were on continuous cycler peritoneal dialysis (CCPD). Fatigue was the most common symptom that led to an increase in the dialysis dose (64%). The prevalence of all the symptoms studied decreased significantly after the increase in dose of dialysis. The weekly peritoneal creatinine clearance increased from 47.35+/-0.88 to 57.34+/-1.401 (P < 0.0001) and the weekly Kt/V increased from 1.8+/-0.03 to 2.27+/-0.05 (P < 0.0001). The daily urine volume and the residual GFR decreased from 318.7+/-36.4 to 151.9+/-22.8 ml/day (P < 0.0001) and 2.05+/-0.2 to 0.82+/-0.12 ml/min (P < 0.0001) respectively during the study period.

The prevalence of all uremic symptoms decreased significantly after the daily dialysate volume was increased. The improvement in symptoms despite the decline in residual function emphasizes the beneficial effect of increased dialysate volume, which produced a significantly higher peritoneal creatinine clearance and Kt/V after the change in the PD prescription.