Effects of intradialytic cycling exercise on exercise capacity, quality of life, physical function and cardiovascular measures in adult haemodialysis patients: A systematic review and meta-analysis

Background. Intradialytic cycling (IDC), delivered during haemodialysis (HD), has the potential to improve many health issues. This systematic review and meta-analysis examine the evidence on the effects of IDC on exercise capacity, quality of life (QoL), physical function and cardiovascular health. Methods. Twenty-four databases were searched alongside Internet and hand searching, and consultation with experts. Eligibility criteria were cluster randomized, randomized and quasi-randomized controlled trials (RCTs) of IDC versus usual care in prevalent adult HD patients. Primary outcome measures were exercise capacity (VO₂ peak and field tests) and QoL. Secondary measures were cardiac and physical function. Results. Thirteen RCTs were eligible. Eight provided data for use in meta-analyses, which indicated no significant change in VO₂ peak (mean difference, MD 1.19 mL/kg/min, 95% confidence interval 1.15 to 3.52, P ¼ 0.3), physical (mean change, MC 1.97, 8.27 to 12.22, P ¼ 0.7) or mental component (MC 3.37, 7.94 to 14.68, P ¼ 0.6) summary scores of the Medical Outcomes Short Form 36, pulse wave velocity (MD 0.57 m/s, 1.55 to 0.41, P ¼ 0.4), systolic (MD 2.28 mmHg, 14.46 to 9.90, P ¼ 0.7) or diastolic blood pressure (MD 2.25 mmHg, 3.01 to 7.50, P ¼ 0.4) following IDC. IDC, however, leads to an improvement in performance on the 6-min walk test (MD 87.84 m, 39.60-136.09, P ¼ 0.0004). All included studies were considered to have high risk of bias. Conclusions. There is insufficient evidence demonstrating whether cycling exercise during HD improves patient outcomes. High-quality, adequately powered RCTs of IDC are required.