Relationship between dialysis adequacy and quality of life in long-term peritoneal dialysis patients

* Objective: The purpose of this study was to compare quality of life (QOL) between peritoneal dialysis (PD) patients with adequate and inadequate tot al solute clearance (TSC). We also tried to determine the relationship betw een QOL and TSC. * Design: A cross-sectional study design was used in which QOL was evaluate d and compared between PD patients with adequate and inadequate TSC, * Setting: The Po unit of a university teaching hospital. * Patients: Sixty-seven patients were recruited, 38 on continuous ambulator y PD and 29 on continuous cycler-assisted PD, * Methods: Patients were divided into adequate and inadequate groups, based on the results of either total urea clearance (Kt/V-urea) or total creatin ine clearance (weekly CCr), The demographic data, dialysis variables, and c linical parameters of these patients were all collected. QOL was evaluated using the SF-36 questionnaire, which contains eight domains and is a compre hensive and validated instrument for QOL evaluation. QOL of patients in ade quate and inadequate groups was compared. The relationship between QOL and TSC was also examined. * Results: Among patients grouped by Kt/V-urea patients in the adequate gro up had significantly higher scores in two domains of the SF-36, that is, ph ysical and emotional role functioning, than did those in the inadequate gro up. The total SF-36 scores were positively correlated with Kt/V-urea when a ll patients were pooled together. However, among patients grouped by weekly CCr, there was no significant difference in any of the eight domains of th e SF-36 between patients in the adequate and inadequate groups. No correlat ion was found between the total SF-36 scores and weekly CCr, * Conclusion: Our study had two important findings: First, PD patients with adequate total solute clearance, based on Kt/V-urea and not on weekly CCr, had a better QOL, Second, Kt/V-urea is better correlated with QOL than wee kly CCr. These findings suggest that Kt/V-urea is a better parameter for th e clinical evaluation of total solute clearance from the viewpoint of QOL.