Impact of different practice patterns on solute transport in peritoneal dialysis

Abstract

Long term peritoneal dialysis (PD) is associated with increased peritoneal solute transport rate (PSTR) and loss of ultrafiltration capacity [1,2], both reflecting acquired structural alterations of the peritoneal membrane. Peritoneal functional changes correlate with hard outcomes, such as technique failure, increased risk of fluid overload and cardiovascular events [3,4]. Moreover, they correlate with encapsulating peritoneal sclerosis (EPS), a rare but severe complication of PD with nearly a 50% mortality rate [5,6].

Given the hard consequences of PSTR increase over time, understanding its determinants and developing clinical strategies to prevent or at least slow down this process might play a key role in PD patients’ survival.

Over the last three decades, PD prescription strategies and clinical practice underwent some major changes, informed by both ongoing scientific evidence (growing awareness of glucose toxicity, association between fluid overload and hard outcomes) and manufacturing innovation (introduction of icodextrin, development of biocompatible dialysis solutions).

We performed a retrospective single-centre longitudinal analysis, from the early 1990s onward, and investigated the association of different clinical approaches with PSTR, and the association of PSTR with transfer to HD and patient survival.

The use of icodextrin and dry dwells was associated with long-term changes in membrane function, with icodextrin patients showing above average PSTR values, but a relatively flatter increase over time, and dry dwells on the other hand being associated with below average PSTR values, despite a relatively steeper increase over time.

PSTR was associated with both patient death and transfer to HD. The association between PSTR and outcome changed across time and it was affected by different clinical practice patterns.

We also analysed the determinants of PSTR at PD start, firstly conducting a single centre analysis, and subsequently validating our findings through a secondary analysis of the international multicentre Global Fluid Study.

We found evidence that PSTR at PD start changed in Stoke and across the UK over time. Different PD prescriptions can partly explain these changes, which seem to be linked to intraperitoneal inflammation, but further investigation is needed to clarify this phenomenon.