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. 2023 Aug 31;2023(8):CD013074. doi: 10.1002/14651858.CD013074.pub2

Konstadinidou‐ND 2002.

Study characteristics
Methods Study design

  • Parallel RCT


Study dates

  • Duration of follow‐up: 6 months

  • Time frame: not reported
Participants Study characteristics

  • Setting: single centre (Renal Unit of AHEPA Hospital)

  • Country: Greece

  • Inclusion criteria: regular HD with an artificial kidney for at least 6 months for 3 sessions/week of 4 hours each

  • Exclusion criteria: unstable hypertension; congestive heart failure (grade > II according to NYHA); cardiac arrhythmias (at least III according to Lown); recent MI or unstable angina; persistent hyperkalaemia before dialysis; DM; active liver disease; bone disease that puts the patient at risk of a fracture; arthritic or orthopaedic problems limiting exercise; peripheral vascular disease; undisciplined patients


Baseline characteristics

  • Number (analysed/randomised): intervention group 1 (16/21); intervention group 2 (10/12); intervention group 3 (10/12); control group (12/13)

  • Mean age ± SD (years): intervention group 1 (46.4 ± 13.9); intervention group 2 (48.3 ± 12.1); intervention group 3 (51.4 ± 12.5); control group (50.2 ± 7.9)

  • Sex (M/F): intervention group 1 (11/5); intervention group 2 (8/2); intervention group 3 (8/2); control group (4/8)

  • Dialysis type: HD

  • Mean dialysis vintage ± SD (years): intervention group 1 (6.5 ± 5.2); intervention group 2 (6 ± 5.5); intervention group 3 (5.2 ± 3.1); control group (6.6 ± 7.2)

  • Comorbidities

    • CVD: not reported

    • Diabetes: intervention group 1 (0/21); intervention group 2 (0/12); intervention group 3 (0/12); control group (0/13)

    • Hypertension: intervention group 1 (10/16); intervention group 2 (6/10); intervention group 3 (6/10); control group (8/12)

    • Depression (clinician diagnosis): not reported
Interventions Intervention classification

  • Non‐pharmacological intervention

  • Indication: study targeting fatigue endpoints (data on fatigue were not reported)


Intervention group 1

  • Supervised aerobic and strengthening training on the non‐dialysis days, 3 times/week


Intervention group 2

  • Supervised exercise program during HD, 3 times/week


Intervention group 3

  • Moderate unsupervised moderate exercise program at home, 3 times/week


Control group

  • Usual lifestyle


Co‐interventions

  • To exclude any impact of the changes in the status of anaemia on the aerobic capacity of patients, we tried to keep the Hb/HCT level stable for all kidney patients (optimum level Hb/HCT ratio was considered 11/33) throughout the study by increasing or decreasing the dose of EPO, whenever necessary

  • All patients were on stable medical therapy during the study

  • Dialysis procedure was kept stable throughout the 6‐month period program (by using the same model of filter and constant composition of the dialysis solution, and by keeping the HD session time constant throughout this period)
Outcomes Outcomes reported

  • Fatigue outcome measures used: validation data available

  • Physical assessment: assessed at the beginning and the end of the study

  • Laboratory tests: assessed at the beginning and the end of the study

  • Lactic acid

    • Photometer: assessed at the beginning and the end of the study

  • Resting ECG: assessed at the beginning and the end of the study

  • BP

    • Mercury sphygmomanometer: was monitored until the end of the study

  • ECG: assessed at the beginning and the end of the study

  • Oxygen consumption (VO2)

    • Spiroergometric: assessed at the beginning and the end of the study

  • Anaerobic threshold (VO2AT)

    • Spiroergometric: assessed at the beginning and the end of the study

  • Respiratory exchange ration

    • Spiroergometric: assessed at the beginning and the end of the study

  • Total exercise time

    • Spiroergometric: assessed at the beginning and the end of the study

  • Pulmonary ventilation

    • Spiroergometric: assessed at the beginning and the end of the study

    • Spirometry: assessed at the beginning and the end of the study

  • Heart rate

    • Spiroergometric: assessed at the beginning and the end of the study

  • Severe hypertension or hypotension: assessed until the end of treatment

  • > 2.5 mm ST segment shift in ECG: during the test it was monitored and recorded every 3 min

  • Adverse events (including severe arrhythmias): assessed until the end of treatment

  • Death: assessed until the end of treatment

  • Fatigue (leg fatigue)

    • Modified Bruce treadmill exercise test: assessed at the beginning and the end of the study
Notes Additional information

  • Funding: not reported

  • Conflicts of interest/disclosures: not reported

  • Trial registration identification number: not applicable

  • A priori published protocol: not reported
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) Unclear risk Sequence generation methods were not reported in sufficient detail to permit judgement
Allocation concealment (selection bias) Unclear risk Method of allocation concealment was not reported in sufficient detail to permit judgement
Blinding of participants and personnel (performance bias)
All outcomes High risk Not reported. However, interventions were different and participants and/or investigators could be aware of the treatment assigned
Blinding of outcome assessment (detection bias)
All outcomes High risk Quote: "Treadmill exercise test to fatigue endpoints. [...] To measure lactic acid, blood samples were taken from the right ear before and 4 min after the end of the exercise test. Lactic acid measurement was carried out in a photometer."
Comment: The outcomes were assessed with an appropriate measure, without differences between groups. Objective measures were used. However, objective and subjective outcomes were assessed
Incomplete outcome data (attrition bias)
All outcomes High risk Quote: "However, during the study 5 patients from Group A, 1 from Group B, 2 from C voluntarily withdrew, while 1 patient from Group B and 1 from D died of causes unrelated to exercise. Finally, 48 patients on HD completed the entire study. [...] Group A had a higher dropout rate (23.8%) and the reasons were lack of time, transportation difficulties and medical reasons unrelated to exercise. The dropout rate in both Groups B and C was 16.7% and the reason for withdrawal was an acute illness."
Comment: 16/21 participants in intervention group 1 (supervised aerobic training), 10/12 participants in intervention group 2 (supervised exercise program), 10/12 participants in intervention group 3 (unsupervised moderate exercise) and 12/13 participants in the control group (usual lifestyle) completed the study (> 5% lost to follow‐up, with differences between groups). Reasons for discontinuations seemed to be not related to the treatment allocation
Selective reporting (reporting bias) High risk Information about the protocol and the statistical analysis plan were not reported. Fatigue was reported using multiple eligible outcome measurements (scales, time points). Fatigue was reported in a format that was extractable for meta‐analysis. All outcomes that should be addressed (fatigue, cardiovascular disease, and death) were not reported.
Other bias Unclear risk There was no evidence of different baseline characteristics, or different non‐randomised co‐interventions between groups. Funding and conflicts of interest were not reported