Cardiorespiratory fitness in adult kidney transplant recipients with stable transplant function and a patent arteriovenous fistula (AVF). Circulatory System
Conditions
Interventions
The intervention in COBALT is surgical disconnection of an arteriovenous fistula. This involves either surgically dividing and oversewing the fistula vein at the site of the original anastomosis onto
continued conservative management, with fistula disconnection only performed if clinically indicated.
Participants will be randomised to either the intervention or standard care in a 1:1 ratio, using
Sponsors
Cambridge University Hospitals NHS Foundation Trust
University of Cambridge
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Current participant inclusion criteria as of 04/02/2022: 1. The participant is an adult, aged 16 years or older 2. The participant is at least one year from kidney transplant and with a patent AVF 3. The participant has stable transplant function (eGFR >35 ml/min/1.73m² and without recent rejection episode or recent decline in graft function) 4. The participant has adequate English to understand the study information by verbal explanation and the written participant information sheet 5. The participant provides full informed consent Previous participant inclusion criteria: 1. Aged =16 years 2. =1 year from kidney transplant and with a patent AVF 3. Stable transplant function (eGFR >35 ml/min/1.73m² and without recent rejection episode or recent decline in graft function) 4. Capacity to provide full informed consent
Exclusion criteria
Exclusion criteria: 1. Lacking capacity 2. CPET is contraindicated 3. Considered to have no further first-line options for AVF creation at their wrist or elbow 4. AVF disconnection is required on clinical grounds
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Feasibility measured using the proportion of approached patients who complete the study (defined as the proportion of all approached patients, who consent to participate, receive the allocated intervention, and complete both cardiopulmonary exercise tests without withdrawing) between recruitment and 6 months | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Feasibility measured using the following: 1.1. Proportion of approached patients who consent to participation measured at recruitment 1.2. Proportion of participants who receive the allocated intervention measured at 0 days 1.3. Proportion of participants who complete both cardiopulmonary exercise tests (CPETs) measured at baseline and 6 months 1.4. Proportion of participants who did not withdraw measured over the 6-month study period 1.5. Proportion of participants who received the allocated intervention and completed both CPETs without withdrawing measured over the 6-month study period 1.6. Proportion of participants who were compliant with wearing wrist accelerometers measured for both 7 day periods at baseline and 6 months 1.7. Rate of patient recruitment at each trial centre measured at recruitment 1.8. Time (days) from providing consent to the first CPET and from CPET to fistula disconnection measured over the 6-month study period 1.9. Patient and clinician perceived acceptability of trial design and processes through qualitative interviews at 6 months 2. Cardiopulmonary fitness measured using peak maximal oxygen consumption (VO2) at baseline and 6 months 3. Physical functioning measured using the physical functioning domain of SF-36 Quality of Life questionnaire score at baseline and 6 months 4. Activity levels measured as mean daily Euclidean norm minus one (ENMO) using accelerometry data.at baseline and 6 months 5. NT-proBNP levels measured using serum NT-proBNP value at baseline and 6 months 6. Blood pressure measured using office blood pressure sphygmomanometer at baseline and 6 months 7. Cardiopulmonary capacity measured using the ventilatory anaerobic threshold (VAT), endurance time, peak workload, O2 pulse, O2 uptake/ work rate slope (VO2/WR), minute ventilation/ CO2 output slope (VE/VCO2), heart rate/ VO2 slope (HR/VO2), and perceived exertion rating (Borg scale) during CPET at baseline and 6 months 8. Kidney transplant function measured using eGFR | — |
Countries
England, Scotland, United Kingdom
Contacts
Public ContactAnna Sidders
Outcome results
None listed