Intradialytic training in patients with end-stage renal disease: a systematic review and meta-analysis of randomized clinical trials assessing the effects of five different training interventions

Objective: Patients with end-stage renal disease (ESRD) undergoing hemodialysis may have reduced dialysis adequacy (Kt/V), low cardiorespiratory fitness, and worse prognosis. Different types of intradialytic training (IDT) may serve as an adjunct therapy for the management of the ESRD. This systematic review and meta-analysis aimed to assess the impact of different types of IDT on clinical outcomes and functional parameters in ESRD.

Methods: PubMed, Embase, CINAHL, Cochrane CENTRAL, Scopus, SPORTDiscus, and Google Scholar were searched for randomized clinical trials in adult patients with ESRD which compared IDT with usual care (UC), without language restrictions and published up to July 2019; a handsearch of references was also performed. Certainty of evidence was assessed using GRADE, and risk of bias in primary studies with the RoB 1.0 tool.

Results: Fifty studies were included (n = 1757). Compared to UC, aerobic IDT improved Kt/V (WMD = 0.08), VO₂peak (WMD = 2.07 mL/kg/min), 6-minute walk test (6MWT) distance (64.98 m), reduced systolic blood pressure (- 10.07 mmHg) and C-reactive protein (- 3.28 mg/L). Resistance training increased 6MWT distance (68.50 m). Combined training increased VO₂peak (5.41 mL/kg/min) and reduced diastolic blood pressure (- 5.76 mmHg). Functional electrostimulation (FES) and inspiratory muscle training (IMT) improved 6MWT distance (54.14 m and 117.62 m, respectively). There was no impact on total cholesterol, interleukin-6, or hemoglobin levels. There was no difference in incidence of adverse events between the IDT and control groups. The certainty of evidence was variable according to the GRADE scale, with most outcomes rated very low certainty. The risk of bias assessment of primary studies showed unclear risk in most.

Conclusions: Aerobic, resistance, and combined training during hemodialysis, as well as FES and IMT, demonstrated to be effective for the treatment of the patient with ESRD. Our data should be interpreted in light of the unclear risk of bias of most evaluated articles and the low to very low certainty of evidence for evaluated outcomes.

Prospero registration id: CRD42017081338. DATA SHARING REPOSITORY: https://osf.io/fpj54/.