# Efficacy in the reduction ratios of middle molecules with the use of medium cut-off dialyzers and reduced dialysate flows: a cohort study

## TL;DR

This study shows that a new dialysis method called HDx is better at removing harmful middle-sized molecules from the blood than traditional methods, with fewer side effects.

## Contribution

The study demonstrates that HDx using Theranova dialyzers outperforms high-flux hemodialysis in removing medium-sized toxins at different dialysate flow rates.

## Key findings

- HDx achieved greater removal of β2-microglobulin and free light chains compared to HF-HD at both dialysate flow rates.
- HDx resulted in 25.9% fewer serious adverse events compared to HF-HD.
- HDx with a dialysate flow rate of 400 mL/min was found to be an effective and sustainable treatment option.

## Abstract

Expanded hemodialysis (HDx) enabled by Theranova increases the clearance of medium-sized molecules, improving clinical outcomes such as hospitalization and mortality. The objective of the study was to compare solute reduction ratios of medium-molecular-weight uremic toxins by HDx versus high-flux hemodialysis (HF-HD) with dialysate flow rates of 400 mL/min and 500 mL/min.

In 287 prevalent adult dialysis patients (mean age 61 years, 67% were men, 42.5% had diabetic kidney disease, and 16.7% had urine output ≥250 mL/day), the solute reduction ratio of circulating middle molecules was determined at 4 weeks and 12 weeks of follow-up in two cohorts, one with HDx (n = 137) and one with HF-HD (n = 150). A mixed-effects repeated measures model was used to evaluate differences between treatment groups. The frequencies of serious adverse events and hospitalization were also calculated.

The HDx group achieved greater efficiency compared with HF-HD group in removing β2-microglobulin and free light chains (lambda and kappa); this superiority was statistically significant for both dialysate flow rates of 400 mL/min and 500 mL/min. We observed 25.9% fewer serious adverse events in the HDx cohort, none of which were causally related to the Theranova dialyzer or HF-HD treatment during 11,409 sessions.

HDx enabled by Theranova dialyzer significantly improved the removal of medium-molecular-weight uremic toxins compared to HF-HD at dialysate flow rates of 500 mL/min and 400 ml/min, with fewer serious adverse events and hospitalization events. These findings support the use of the environmentally sustainable dialysis treatment of HDx with dialysate flow rate of 400 ml/min.