#2014 Exercise safety and efficacy as a rehabilitation therapy for patients on hemodiafiltration: a 6-month controlled study
Authors: Andrade Jessica , Heitmann Ayden , Rodrigues Adelson , Biluca Bruno , Freitas Rene , Reis Thiago , Goes Miguel , Oliveira Mayron 
Published: May 2024

Abstract

Background and Aims
Individuals with chronic kidney disease (CKD) stage 5D face challenges due to the accumulation of uremic toxins. Hemodiafiltration (HDF) stands out for its efficacy in removing solutes of various molecular weights, offering mortality benefits. Although exercise rehabilitation is established as a beneficial adjunct therapy for patients on maintenance hemodialysis, its impact on maintenance HDF programs remains understudied. The primary aim was to evaluate the safety and efficacy of exercise as rehabilitation in patients undergoing HDF. The secondary aim was to compare the outcomes between intra- and inter-HDF exercise sessions.

Method
This study enrolled CKD 5D patients at Fenix Nephrology Group from 2021 to 2023. The assessment occurred at the initiation of the exercise program and after six months of exercise rehabilitation. Physical tests included the step-test, handgrip, and one-repetition maximum (1RM), and the Kidney Disease Quality of Life Short Form (KDQOL-SF), a patient-reported outcome measure. The urea reduction ratio (URR) reflected HDF adequacy. Patients engaged in twice-weekly aerobic exercises achieving 70% of maximum heart rate and resistance exercises (60% 1RM).

Results
Data from 234 patients were obtained, and 81 were not on the exercise program. From the remaining 153 patients, we excluded 64. Twelve patients were excluded because underwent kidney transplantation during their participation, 41 had incomplete data, and 11 patients carried out less than 80% of the scheduled exercise sessions. We included in our final analysis data from 89 patients (55 ± 15 years; 58.4% male). The mean dialysis vintage was 9 ± 7 years, including high-flux hemodialysis and HDF. Specifically, for HDF, the mean dialysis vintage was 5 ± 4 years. Mean exercise session adherence was 94 ± 4%, and the mean number of sessions was 39 ± 4. Concerning the performance outcomes, we observed significant improvements in the step-test (80 ± 22 to 93 ± 25 steps; p &lt; 0.001) and handgrip measurement (28 ± 7 to 30 ± 7 kgf; p &lt; 0.001), alongside an approximate 4% increase in lean body mass (13 ± 2 to 14 ± 2 kg; p &lt; 0.001) during the 6 months. The KDQOL-SF improved in physical functioning (64 ± 22 to 72 ± 23; p &lt; 0.001), general health (55 ± 23 to 61 ± 2; p = 0.01), social function (73 ± 26 to 80 ± 21; p = 0.004), physical (43 ± 9 to 47 ± 8; p &lt; 0.001) and mental composite scores (46 ± 10 to 48 ± 9; p = 0.04), along with a reduction in fatigue (57 ± 17 to 60 ± 17; p = 0.03). A similar favorable trend was observed for the URR (68 ± 10% vs. 71 ± 8%; p &lt; 0.05). We also analyzed the exercise rehabilitation program in two different groups. Thirty-five patients carried out intradialytic exercise (i.e., during the dialysis session). In this group, the mean dialysis vintage was 10 ± 7 years and specifically 5 ± 3 years on HDF. The other group included 54 patients performing interdialytic exercise (i.e., pre- or post-session). In this group, the mean dialysis vintage was 8 ± 6 years and specifically 4 ± 2 years on HDF. We did not observe complications during the exercise program, and no sessions were interrupted due to adverse events. Demographic and anthropometric data (age, sex, weight, and body mass index) were comparable between the groups. Furthermore, exercise performance was equivalent in both groups.

Conclusion
Our findings suggest that a supervised exercise program for maintenance dialysis patients performing HDF is safe and efficacious, yielding substantial improvements in patient-reported and performance outcomes. Notably, the positive effects of exercise persisted whether conducted during intradialytic or interdialytic periods.