Impact of incremental peritoneal dialysis on long-term nutritional trajectories in end-stage kidney disease: a...

Incremental peritoneal dialysis (IPD) seeks to reduce the immediate treatment burden by utilizing residual kidney function. However, its long-term effects on nutritional status remain unclear. This study investigated how an initial IPD strategy influences the longitudinal trajectories of the prognostic nutritional index (PNI) in patients with end-stage kidney disease (ESKD).

This retrospective study included patients who received peritoneal dialysis (PD) at the Second Hospital of Jilin University between January 2016 and July 2024. We employed linear mixed-effects models to analyze population-level trends in PNI. Group-based trajectory modeling (GBTM) was utilized to identify patterns of PNI evolution, while multivariable Cox models assessed the relationship between these patterns and all-cause mortality. Additionally, multivariable logistic regression, which included multiple imputation and entropy balancing-derived inverse probability weights (IPW), was used to explore the independent association between the type of dialysis and trajectory membership.

A total of 311 patients who initiated PD between 2016 and 2024 were included, of whom 230 received full-dose PD and 81 received IPD. Throughout the follow-up period, 80.25% of patients on IPD were transitioned to full-dose PD at a median of 10 months. Mixed-effects modeling indicated no significant differences in PNI levels or rates of decline between the two modalities (time-by-modality interaction P = 0.378). GBTM revealed three distinct PNI trajectories: low, moderate, and high. The high-level trajectory was associated with a significantly reduced risk of mortality compared to the low-level group (fully adjusted HR = 0.17, P < 0.001). However, in IPW-adjusted models, the initial dialysis modality did not show an independent association with any specific PNI trajectory. These findings remained consistent across multiple sensitivity analyses.

When accompanied by dynamic prescription adjustments, IPD sustains mid- to long-term nutritional trajectories that are comparable to those achieved with full-dose PD.