P0954effects of intradialytic exercise for advanced-aged patients undergoing hemodialysis: a randomized controlled trial

Abstract Background and Aims Exercise therapy, a treatment for poor physical function in patients undergoing dialysis, has shown some evidence of effectiveness. Some meta-analysis indicated the effectiveness of exercise interventions on exercise tolerance, muscle strength, and quality of life. However, most studies assessing the effects of exercise in patients undergoing hemodialysis have involved middle-aged patients; few data for advanced-age patients undergoing hemodialysis are available. The concept of exercise intervention for young to middle-aged patients undergoing hemodialysis is not entirely applicable to older patients, and whether exercise training improves physical function in older patients undergoing hemodialysis remains unclear. Therefore, the present randomized controlled trial (RCT) was performed to verify the effectiveness of exercise therapy in advanced-age patients undergoing hemodialysis. Method In this single-center, prospective, parallel RCT, all patients were randomly assigned to either the exercise or control group. The inclusion criteria were an age of ≥70 years and no acute or chronic medical conditions that would preclude assessment of the outcome measures or the performance of exercise. Ethical approval was provided by Seirei Christopher University. Patients randomized to the exercise group were offered 6 months of exercise training three times a week. The training program involved both resistance and aerobic training exercises. Four types of resistance exercises were performed using an elastic tube. The exercise intensity was adjusted by the tube stiffness to achieve a target a Borg score of 13 to 15 for fatigue. The aerobic exercise program consisted of ergometer cycling for 20 minutes. The exercise intensity was adjusted to a target Borg score of 13. The leg extremity muscle strength (LES), Short Physical Performance Battery (SPPB) score, and 10-m walk speed were evaluated before and after 6 months of training. The group effect was analyzed by analysis of covariance (ANCOVA) using the change in scores (Δ, post minus pre) as the dependent variable and baseline value of the dependent variable in the model as a covariate. Additional covariates for the ANCOVA models were identified by comparison of group means at baseline. The effect size (ES) was calculated as the change in the exercise group minus the change in the control group divided by the pooled standard deviation, corrected for sample size. Results Among the 101 randomly assigned patients, 17 (16.8%) were unavailable for follow-up testing. As a result, 84 patients (44 in the exercise group and 40 in the control group) were included in the analysis. The group comparison revealed no differences in any baseline characteristics between the two groups. Statistically significant increases in the ΔSPPB score were found in the exercise group (0.7 ± 2.1) as compared with the control group (−0.4 ± 2.0), with a moderate ES of 0.57. The ΔLES and Δ10-m walk speed were not significantly different between the groups, and the ES was 0.18 and 0.00, respectively. Conclusion The purpose of this RCT was to verify the effectiveness of exercise therapy in advanced-age patients undergoing hemodialysis. After 6 months of aerobic and resistance intradialytic training, we observed statistically significant increases in the ΔSPPB score in the exercise group as compared with the control group, with a moderate ES of 0.57. Exercise therapy improves physical function in older patients undergoing dialysis, and the effectiveness may differ from that in middle-aged patients; however, this change is clinically important in older patients.