Background: Whether or not clinically implementable exercise interventions in haemodialysis patients improve quality of life remains unknown.
Objectives: The PEDAL (PrEscription of intraDialytic exercise to improve quAlity of Life in patients with chronic kidney disease) trial evaluated the clinical effectiveness and cost-effectiveness of a 6-month intradialytic exercise programme on quality of life compared with usual care for haemodialysis patients.
Design: We conducted a prospective, multicentre randomised controlled trial of haemodialysis patients from five haemodialysis centres in the UK and randomly assigned them (1 : 1) using a web-based system to (1) intradialytic exercise training plus usual-care maintenance haemodialysis or (2) usual-care maintenance haemodialysis.
Setting: The setting was five dialysis units across the UK from 2015 to 2019.
Participants: The participants were adult patients with end-stage kidney disease who had been receiving haemodialysis therapy for > 1 year.
Interventions: Participants were randomised to receive usual-care maintenance haemodialysis or usual-care maintenance haemodialysis plus intradialytic exercise training.
Main outcome measures: The primary outcome of the study was change in Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score (from baseline to 6 months). Cost-effectiveness was determined using health economic analysis and the EuroQol-5 Dimensions, five-level version. Additional secondary outcomes included quality of life (Kidney Disease Quality of Life Short Form, version 1.3, generic multi-item and burden of kidney disease scales), functional capacity (sit-to-stand 60 and 10-metre Timed Up and Go tests), physiological measures (peak oxygen uptake and arterial stiffness), habitual physical activity levels (measured by the International Physical Activity Questionnaire and Duke Activity Status Index), fear of falling (measured by the Tinetti Falls Efficacy Scale), anthropometric measures (body mass index and waist circumference), clinical measures (including medication use, resting blood pressure, routine biochemistry, hospitalisations) and harms associated with intervention. A nested qualitative study was conducted.
Results: We randomised 379 participants; 335 patients completed baseline assessments and 243 patients (intervention, n = 127; control, n = 116) completed 6-month assessments. The mean difference in change in physical component summary score from baseline to 6 months between the intervention group and control group was 2.4 arbitrary units (95% confidence interval -0.1 to 4.8 arbitrary units; p = 0.055). Participants in the intervention group had poor compliance (49%) and very poor adherence (18%) to the exercise prescription. The cost of delivering the intervention ranged from £463 to £848 per participant per year. The number of participants with harms was similar in the intervention (n = 69) and control (n = 56) groups.
Limitations: Participants could not be blinded to the intervention; however, outcome assessors were blinded to group allocation.
Conclusions: On trial completion the primary outcome (Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score) was not statistically improved compared with usual care. The findings suggest that implementation of an intradialytic cycling programme is not an effective intervention to enhance health-related quality of life, as delivered to this cohort of deconditioned patients receiving haemodialysis.
Future work: The benefits of longer interventions, including progressive resistance training, should be confirmed even if extradialytic delivery is required. Future studies also need to evaluate whether or not there are subgroups of patients who may benefit from this type of intervention, and whether or not there is scope to optimise the exercise intervention to improve compliance and clinical effectiveness.
Trial registration: Current Controlled Trials ISRCTN83508514.
Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 40. See the NIHR Journals Library website for further project information.
Keywords: CHRONIC KIDNEY DISEASE; PHYSICAL ACTIVITY; PHYSICAL FUNCTION; REHABILITATION.
Although the benefits of exercise in the general population are well recognised, we do not know if offering cycling exercise during haemodialysis is an effective way to improve quality of life, and if this would be a cost-effective way to provide exercise training for this patient population. To determine whether or not this type of exercise training is effective, and provides value for money, this study compared cycling during haemodialysis treatment, three times per week for 6 months, with usual care that does not include routine delivery of any exercise training. Five regions of the UK were included in the study. We compared the results from the two groups at the start of the study and at 6 months, after correcting for age and diabetes status. We also assessed the economic impact of delivering the cycling during haemodialysis programme and interviewed people from different regions of the UK in both groups. The baseline assessments revealed a deconditioned population in the study. There was no difference in quality of life or any physical function measures between the group that performed cycling during haemodialysis and the usual-care group. Compliance with the exercise intervention was very poor. Interviews with patients showed that patient engagement with the exercise training was linked to the presence of an exercise culture, and leadership to provide this, in the renal unit. An economic evaluation showed that delivering cycling during haemodialysis would not be value for money when delivered to a deconditioned haemodialysis population. Ways to engage patients with exercise training during their haemodialysis treatment should be explored further.