SASH: Sodium Accumulation Study In Haemodialysis

Study Overview
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Brief Summary
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Haemodialysis (HD) sustains life in patients with end-stage kidney disease (ESKD) but is associated with a marked increase in incidence of cardiovascular disease (CVD) and high annual mortality rates. The pathogenesis of CVD in patients on HD is multifactorial and complex but hypertension is thought to be a major contributing factor. Sodium balance is normally regulated by the kidneys in health but has to be achieved by sodium removal during HD for those with ESKD. Recent evidence suggests that accumulation of sodium in the skin and / or muscle may be a critical factor impacting the development of hypertension and CVD in patients with ESKD and non-invasive methods are therefore required to study tissue sodium accumulation in this context. This study aims to determine the change in skin and muscle sodium content in patients undergoing haemodialysis. Participants will have a single haemodialysis session, and undergo two MRI scans (one prior to and one following dialysis).

Detailed Description
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It has been proposed that tissue sodium accumulation in skin and/or muscle is a key factor in hypertension. 23Na MRI allows the assessment of skin and muscle sodium storage and will therefore be a valuable tool in elucidating the role of tissue sodium accumulation in the pathogenesis of salt-sensitive hypertension and cardiovascular morbidity and mortality. Moreover, if haemodialysis in patients with end-stage kidney disease (ESKD) results in changes in tissue sodium, the development of 23Na skin and muscle measures would allow for a method to correlate skin tissue sodium content with detailed cardiovascular and functional assessments. Participants will have a single haemodialysis session, and undergo two MRI scans (one prior to and one following dialysis), in conjunction with clinical data collection (eg. blood samples, bioimpedance analysis, skin autoflorescence).

Official Title
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Sodium Accumulation Study In Haemodialysis

Conditions
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Haemodialysis, End Stage Renal Disease on Dialysis

Intervention / Treatment
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* Other: No intervention will be given in this study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 50-75 years inclusive Male patients with CKD stage 5 receiving chronic haemodialysis Patient has been dialysis dependent for at least 3 months Must be able to follow simple instruction in English (on safety ground for MRI scans) and be able to understand the nature and requirements of the study Exclusion Criteria: Active infection or malignancy Amputee Pregnancy Contraindication to MRI scanning including claustrophobia, pacemaker, metallic implants etc Unable or unwilling to provide informed consent Medical conditions or overall physical frailty precludes scan session in opinion of investigator Any condition which could interfere with the patient's ability to comply with the study

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients on haemodialysis<br>5 patients on haemodialysis will be recruited. The study involves a single dialysis session and two MRI scans (one prior and one following dialysis) and collection of clinical data. | Other: No intervention will be given in this study<br>* No intervention will be given in this study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ascertainment of MRI measures of skin and muscle sodium content in 100% of patients studied | Sodium imaging of the skin and muscle of the upper calf will be performed using a range of sequences to quantify sodium in the skin and muscle using both fast-field-echo (FFE) and ultrashort TE (UTE) imaging techniques. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To study skin and muscle sodium in haemodialysis patients and compare with previously reported healthy normal values | Sodium imaging of the skin and muscle of the upper calf will be performed using a range of sequences to quantify sodium in the skin and muscle using both fast-field-echo (FFE) and ultrashort TE (UTE) imaging techniques | 6 months | 
| To measure degree of change in skin and muscle sodium content in relation to a single haemodialysis treatment | Quantification of sodium in skin and muscle and compare finding before and after dialysis | 6 months | 
| To determine associations between skin and muscle sodium content and blood pressure, and change in skin and muscle sodium content with ultrafiltration volume and plasma-dialysate sodium gradient | By clinical data collection before, during and after dialysis | 6 months | 
| To determine associations between skin and muscle sodium content and cardiac function as determined by left ventricular mass (LVM) pressure | MRI abdominal coil will be used to collect cardiac MRI scans | 6 months |