Incremental peritoneal dialysis: Is it better for preservation of residual kidney function and clinical outcomes?

Introduction: Incremental peritoneal dialysis (IPD) is based on the prescription of a dose lower than the standard (SPD). The combination of residual kidney function (RKF) and peritoneal clearance achieves clearance goals. The aim of this study is to compare the outcomes of IPD with SPD. Materials and methods: This was a single-center, retrospective study that included a cohort of prevalent peritoneal dialysis (PD) adults. Patients were assigned according to their first PD protocol in two groups - group A: IPD protocol (continuous ambulatory PD: less than 4 dwells daily, less than 2 L dwell volume, and/or treatment less than 7 days/week; automated PD: without a long dwell, less than 10 L daily delivered, and/or treatment for less than 7 days/week); group B: SPD protocol. Results: 87 PD patients were included, 65.5% underwent IPD. The median follow-up time was 23 months (IQR 15 - 35). IPD had a higher glomerular filtration ratio (7 vs. 3.7, mL/min/1.73m(2), p < 0.001) in the first 6 months, and after 24 months (4.8 vs. 1.9, mL/min/1.73m(2), p = 0.002). IPD protocol was independently associated with GFR = 5 mL/min/1.73m(2) at 24 months (OR 13 per point, 95% CI 1.48 - 114.36, p = 0.021). IPD was also associated with a longer technique survival (log-rank test = 4.928, p = 0.026), lower hospital admissions per year (0.23 vs. 0.5, p = 0.001), and lower mortality (1.8% vs. 13.3%, p = 0.027). Cox regression demonstrated that IPD (HR 0.30; 95% CI 0.098 - 0.93); p = 0.036) was associated with a decrease in the risk of technique failure. Conclusion: The prescription of IPD seems to be beneficial, in terms of outcomes, for patients with substantial RKF.