#1067 The impact of hemodialysis (HD) versus hemodiafiltration (HDF) on the effect of intradialytic exercise: a multicentre cohort study

Abstract Background and Aims Diminished physical function in HD patients is a critical issue, necessitating strategic approaches to enhance the efficacy of exercise therapy. The differential impacts of HD and HDF on solute clearance, albumin loss, uremic conditions, and malnutrition could influence the success of exercise interventions. Presently, empirical evidence for this is lacking. This investigation explores how HD and HDF modalities influence the efficacy of exercise therapy administered during dialysis sessions. Method This study encompassed intradialytic resistance exercises, involving 414 patients with end-stage renal disease across 10 centers. Participants were voluntarily enlisted in an exercise regimen during their dialysis sessions. The intradialytic regimen comprised stretching and four types of resistance exercises utilizing elastic tubes, conducted thrice weekly over six months. Parameters such as 10-meter walking speed, knee extensor muscle strength, serum albumin levels (Alb), normalized protein catabolic rate (nPCR), and Creatinine Generation Rate (%CGR) were assessed pre-and post-intervention. Statistical analysis included propensity score matching to adjust for baseline characteristics, segregating patients into HD and HDF cohorts. Changes in the aforementioned indicators before and after intervention (Δ) were calculated. Analytical methods included paired t-tests for within-group comparisons and independent t-tests for between-group comparisons of Δ values. A 5% risk threshold was established for statistical significance. Ethical clearance was obtained from the Seirei Christopher University Ethics Committee. Results A propensity score matching yielded 70 matched pairs. There were no significant differences in baseline subject characteristics after propensity score matching. Within-group analyses in the HD group revealed significant improvements in 10-meter walking speed (1.42 ± 0.41→1.60 ± 0.46 m/s, p = 0.000), knee extensor strength (44.3 ± 14.7→49.6 ± 13.8%, p = 0.000), and a reduction in Kt/V (1.69 ± 0.32→1.64 ± 0.32, p = 0.006) after six months. The HDF group significantly enhanced 10-meter walking speed (1.54 ± 0.40→1.72 ± 0.40, p = 0.000), knee extensor muscle strength (51.7 ± 17.1→57.4 ± 17.7%, p = 0.000), nPCR (0.88 ± 0.15→0.94 ± 0.18, p = 0.009), and %CGR (106.3 ± 23.2→112.9 ± 25.2, p = 0.002) (pre to post value, respectively). There are no significant differences in other variables between pre- and post-values in each group. Comparative analysis between groups demonstrated a significantly lower ΔAlb (HD 0.04 ± 0.24 HDF −0.05 ± 0.27, p = 0.045)and a higher 7, p =0(HD 1.47 ± 18.2 HDF 6.65 ± 17.2, p = 0.004)in the HDF group compared to the HD group. Conclusion The study demonstrated a notable HDF group improvement in %CGR, an indicator of muscle mass, despite a decrease in albumin levels. This suggests that albumin loss due to HDF minimally affects the augmentation of physical function. The findings suggest integrating exercise therapy with HDF may positively influence protein consumption and muscle mass enhancement.