Effect of intradialytic exercise therapy on life outcomes in maintenance hemodialysis patients: a multicenter study

BACKGROUND: Intradialytic exercise improves physical function and quality of life (QOL) in patients on hemodialysis (HD), but previous studies on life outcomes are scarce. Our aim was to investigate the impact of intradialytic exercise on all-cause mortality in patients on HD. METHODS: This retrospective observational study enrolled outpatients on hemodialysis at 17 Kaikoukai Group facilities as of 2018. The intradialytic exercise group received muscle strength training using Thera-band, while the control group received regular HD treatment alone. Mortality outcomes were observed until December 2021. Statistical analysis included survival analysis using Kaplan-Meier curves and Cox proportional hazards regression analysis. After adjusting for multiple confounding factors across five progressively adjusted models, hazard ratios (HRs) and 95% confidence intervals (CIs) for overall mortality were estimated. RESULTS: There were 1911 subjects (375 patients in the intervention group and 1536 patients in the control group), and the median observation period was 36 months. Forty-seven patients (12.5%) in the intradialytic exercise group and 276 patients (17.9%) in the control group died. The intervention group had a significantly higher survival rate than the control group (P < .05), which remained significant after adjustment for confounding factors. [Model 1: HR 0.663 (0.486 to 0.904), Model 2: HR 0.721 (0.526 to 0.987), Model 3: HR 0.710 (0.520 to 0.970), Model 4: HR 0.692 (0.508 to 0.944), Model 5: HR 0.690 (0.504 to 0.945)]. CONCLUSIONS: Intradialytic exercise was associated with an approximately 30% reduction in all-cause mortality, even when patient background and dialysis conditions were taken into account; Intradialytic exercise may be associated with improved survival outcomes in HD patients.