Background
Evidence comparing different exercise modalities in individuals undergoing hemodialysis remains incipient. Our aim was to conduct a systematic review and network meta-analysis of randomized clinical trials to compare and synthesize the efficacy of five different intradialytic exercise modalities and home-based training in this population.
Design, setting, participants, & measurements
Studies were searched in PubMed/MEDLINE, Cochrane Library, Embase, Cinahl, and Scopus from their inception to September 19, 2022. We used traditional random-effects models and Bayesian network meta-analysis models. The risk of bias was assessed by the RoB 2.0 tool, and the assessment of confidence in the results through the CINeMA tool.
Results
Seventy-eight studies involving 3,326 participants were included. Our network meta-analysis showed that combined training was the intervention with the best performance to increase VO2peak (mean difference [MD] = 3.94 mL.kg.min; 95% credible interval [CrI], 2.38 to 5.76) and to reduce diastolic blood pressure (MD = −5.19 mmHg; 95%CrI, −9.35 to −0.96) compared to the usual care group. Inspiratory muscle training was the intervention that most improved the 6-minute walk test distance (MD = 70.97 m; 95%CrI, 18.09 to 129.87). C-reactive protein decreased in resistance training (MD = −2.6 mg/L; 95%CrI, −4.97 to −0.33) and aerobic training (MD = −1.4 mg/L; 95%CrI, −3.15 to −0.06). Kt/V improved in aerobic training (MD = 0.11; 95%CrI, 0.02 to 0.18), and SF-36 physical functioning outcomes improved in resistance training (MD = 10.66 points; 95%Crl, 1.91 to 20.22). No intradialytic exercise modality was superior to others or comparable with home-based training in improving the evaluated outcomes. Subgroup analysis revealed that exercise interventions >12 weeks improved functional capacity more than interventions ≤12 weeks, and that combined training reduces diastolic blood pressure only after 12 weeks of follow-up. Furthermore, our results suggest that moderate or moderate-to-vigorous intensity training leads to more pronounced improvements in functional capacity, while mild or mild-to-moderate intensity training does not have the same effect. In this review, most of the included studies were assessed as having some concern, which resulted in a low to very low level of confidence in the overall findings.
Conclusions
Both intradialytic training and home-based training can promote benefits for individuals undergoing hemodialysis, with no evidence of the superiority of either training modality over the other.