#1277 Comparing advanced glycation end products removal in super high-flux hemodialysis versus high-volume hemodiafiltration: a randomized, crossover study

Abstract Background and Aims Expanded hemodialysis using super high-flux membrane, is a promising therapy for effectively clearing middle molecule uremic toxins. However, its impact on advanced glycation end products (AGEs), which is related to an increase in cardiovascular mortality 1, remains inconclusive. Previous studies demonstrated that AGEs increased over time in patients treated with high-flux hemodialysis (HD) 2, 3 while remaining stabilized in online hemodiafiltration (ol-HDF) 3. This study aims to compare the longitudinal tissue AGEs measured by skin autofluorescence (SAF) between super high-flux hemodialysis (SHF-HD) and high-volume post-dilution ol-HDF. Method In this open-label prospective cross-over 24-week trial, twenty-two prevalent HD patients were randomly assigned to undergone two sequences of 24-week treatment periods: SHF-HD followed by high-volume postdilution ol-HDF or vice versa, with a 4-week wash-out period with high-flux HD between. SAF was measured at baseline and 24 weeks. Midweek pre-HD measurements of beta-2 microglobulin (B2M), serum albumin, normalized protein catabolic rate (NPCR) and Kt/V were obtained every 8 weeks. The amount of dialysate albumin was collected by continuous sampling of spent dialysate method and determined by immunoturbidimetric assay Results Seventeen out of twenty-two patients completed the study. At baseline, SAF levels (3.88 ± 0.14 vs 3.99 ± 0.14 AU, p = 0.463) and pre-HD B2M (22.66 ± 1.41 vs 21.09 ± 1.41 mg/L, p = 0.228) were similar between the SHF-HD and ol-HDF groups. After 24 weeks, SAF levels showed no significant change in SHF-HD (from 3.88 ± 0.14 to 3.91 ± 0.14 AU, p = 0.846) and ol-HDF (from 3.99 ± 0.14 to 3.95 ± 0.14 AU, p = 0.796), with a mean difference of change 0.06 (95% CI −0.34, 0.47, p = 0.75). Similarly, mid-week pre-HD serum B2M at 24 weeks exhibited no significant change in the SHF-HD group (22.66 ± 1.41 to 22.18 ± 1.47 mg/L, p = 0.722) and the ol-HDF group (21.09 ± 1.41 to 21.83 ± 1.45 mg/L, p = 0.577), with a mean difference of change −1.22 (95% CI −4.94, 2.49, p = 0.519). The spKt/V urea did not exhibit any notable differences. Furthermore, pre-HD levels of all small uremic toxins after the 24-week periods did not differ between both groups. Nutritional status measured by serum albumin and NPCR were comparable despite higher dialysate albumin loss in postdilution ol-HDF group (0.82 ± 0.04 vs 1.92 ± 0.12 g, p 0.001 in SHF-HD and ol-HDF, respectively) Conclusion After 24 weeks of treatment, SHF-HD demonstrated levels of AGEs, pre-HD serum B2M, and serum albumin comparable to high-volume ol-HDF. If high-volume postdilution ol-HDF is not feasible, SHF-HD may serve as a valuable alternative treatment for stabilizing AGEs in chronic hemodialysis patients.