#1647 Clinical insights into incremental hemodialysis: a retrospective analysis of patient persistence and outcomes
Authors: Betti Paolo , Colombo Francesca , Avino Monica , Miglio Roberta , Bruno Giancarlo , Bucci Romina , Curreri Manuela , Battaglia Carmelo , Caruso Maria Rosa 
Published: May 2024

Abstract

Background and Aims
Incremental haemodialysis has been proposed as an alternative to standard thrice-weekly haemodialysis for incident patients with significant residual kidney function. Definition is not unique, but it is mostly intended as twice weekly dialysis. Its diffusion is not known since there are no public registers in Europe, but it is adopted in some dialysis facilities, while in others is not, with geographical differences.
In our centre incremental haemodialysis in adopted for some patients, based on the clinical judgement, without a strict protocol. We retrospectively analysed clinical outcomes of the incident patients of the last 36 months, to understand which patients may benefit more from this approach, how long it is viable and the clinical outcomes.

Method
Retrospective observational analysis of incident patients of the last 36 months, without serious rapidly evolving disease. Focus was on persistence in twice-weekly dialysis, nutritional parameters, residual kidney function, hospital admissions and economic considerations.
36 patients started haemodialysis with a 2-times per week schedule while 13 with full dose dialysis. At baseline, there were no significant differences on age, sex, serum albumin or vascular access. 5 patients in full dose group were anuric for bilateral nephrectomy or rapidly progressive kidney disease, while all patients in incremental group had significant residual kidney function (average creatinine clearance: 7.1 ml/min).

Results
During the follow up period, 19/36 patients’ weekly dialysis sessions were incremented to three after a median time of 280 days, and 17/36 were still on 2-dialysis with a median follow-up time of 228 days. The reason for transition to three dialysis per week was residual kidney function loss except for a case of pericarditis.
Persistence in incremental dialysis was &gt;80% at 6 months and 44% at 1 year (Fig. 1a). We observed a significantly reduced persistence in patients with low ultrafiltration at 2nd month of dialysis (&lt;1.7% of weight per session – 1 kg for a 60 kg patient-) and a reduced persistence with pre-dialysis systolic blood pressure &lt;150 mmHg at 2nd month (Fig. 1b-c). Persistence was not different in more frail patients (elderly, dialyzed with a central venous line or with lower baseline albumin).
Serum albumin increase was higher in patients in incremental haemodialysis at 6 months, with a borderline statistically significant difference, and similar at 1 year (Fig. 2a-b). The average weight was stable in both groups (Fig. 2). Hospital admissions were lower in the incremental group, and number of days of hospitalization per 1000 patients’ days were lower (24 vs 41 days).
Thanks to the incremental approach, about 1600 dialysis sessions were avoided for the patients included in the analysis, with significant reduction of economic impact for the public healthcare and the possibility to treat more patients.
Data was insufficient to make conclusions on kidney function preservation.

Conclusion
Incremental approach is valid in our experience. These data give useful information on how long we can expect patients to persist in 2-weekly dialysis and on which patients might benefit more and longer of this approach.
The patients with better volume control, which reflect in adequate blood pressure control and low ultrafiltration rate, show a significantly longer persistence in incremental dialysis. The approach is valid also for frail patients.
We also found better albumin and lower hospital admission rates that could be related with a reduced health-care exposition and better overall patients’ well-being, with adequate uremic symptoms control. The reduction on the hospital admissions has been already observed, while the albumin better rise is a new finding and should be confirmed in a randomized or at least larger study.
Waiting for the results of the on-going randomized clinical trials, incremental haemodialysis might be the new standard-of-care for a subset incident haemodialysis patients.