A systematic review and meta-analysis of the efficacy of aerobic exercise combined with resistance training on maintenance hemodialysis patients

Background: Chronic kidney disease (CKD) is a life-threatening illness that causes significant pain to patients, this serious impact on patient's physical fitness and quality of life. Previous studies have found that exercise training has a positive impact on improving CKD patients' symptoms. In order to improve patients' physical function and quality of life, this meta-analysis aimed to evaluate the application value of aerobic exercise combined with resistance training in maintenance hemodialysis (MHD) patients.

Methods: A computer search was conducted of PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu databases. The search keywords were: "chronic kidney disease", "end-stage renal disease", "hemodialysis", "maintenance hemodialysis", "exercise", "aerobic exercise", "resistance exercise", "combined exercise", and "physical exercise". Included studies should meet the following criteria, the study population is MHD patients, the intervention is aerobic exercise combined with resistance training, and a randomized controlled study with clearly documented outcome indicators. The Cochrane risk-of-bias tool was used to evaluate the quality of the included studies, and the meta-analysis was performed by RevMan 5.20 software (Cochrane Collaboration).

Results: A total of seven articles met the inclusion criteria. The included studies were assessed for risk of bias and met the inclusion criteria. The results of the meta-analysis showed significant differences between patients who received aerobic exercise combined with resistance training and control patients (the rest treatment was same as the study group) in the urea clearance index [mean difference (MD) =0.16, 95% confidence interval (CI): 0.10, 0.21], mental health (MD =7.54, 95% CI: 2.74, 12.35) and social functioning (MD =9.98, 95% CI: 1.52, 18.44). However, there was no significant difference in physical functioning between the two groups (MD =1.26, 95% CI: -1.20, 3.71).

Discussion: Although aerobic exercise combined with resistance training did not improve the physical functioning of MHD patients, it improved their urea clearance, mental health, and social functioning and positively affected their quality of life, risk of bias should also be considered. In the future, multi-center studies with larger samples should be used to explore the effects of aerobic exercise combined with resistance training on MHD patients.