Testing Tissue Sodium Stores in CAPD Patients-Aims 1 & 2

Testing Tissue Sodium Stores in Continuous Ambulatory Peritoneal Dialysis (CAPD) Patients Receiving Icodextrin or Glucose-Based Dialysate, A Randomized Trial-Aims 1 & 2

The investigators' overarching goal is to improve long-term outcomes for end stage renal disease (ESRD) patients. In this study we focus specifically on patients receiving peritoneal dialysis (PD). Volume regulation in PD patients is related to hypertension, heart failure, nutritional status, and survival. Salt (NaCl) is the body's ion transport target to normally regulate volume via the kidneys; however, in hemodialysis (HD) patients the dialyser or in PD patients the peritoneal membrane, must serve that purpose. Determining volume status in PD patients is not easy and monitoring sodium (Na+) is more difficult still. The investigators have developed a novel, noninvasive approach to this problem involving 23Na+ magnetic resonance imaging (Na-MRI). Na+ is stored bound to proteoglycans in mostly the skin. Our technique measures Na+ in skin and skeletal muscle. In this study, we propose to apply this novel technique to PD patients.

Aim 1. To determine Na+ stores in PD patients, to compare Na+ stores to normal controls using Na-MRI technique, and to correlate Na+ stores by Na-MRI with multifrequency bioimpedance measurements and cross-sectional clinical data.

Hypothesis: Na+ stores are increased in PD patients compared to normal controls; they are increased in PD patients with volume expansion and in those patients with high soluble vascular endothelial growth factor receptor-3 (sFlt-4) levels.

Aim 2. To determine the utility of Na-MRI as an assessment of preserving residual renal function in PD patients.

Hypothesis: Extracellular volume expansion as measured by multifrequency bioimpedance was found to have no utility in predicting preservation of residual renal function in PD patients. The investigators hypothesize that Na+ stores as determined by 23Na-MRI will fulfill that function and will be inversely, rather than directly, related.

Study Overview

• Status: Completed
• Conditions: End Stage Renal Disease

• Study Type: Observational
• Enrollment (Actual): 41

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Nashville, Tennessee, United States, 37232
      • Vanderbilt University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients on PD and healthy controls

Description

Inclusion Criteria:

Both subject groups:

• Age 18 to 80 years;
• BMI < 40;
• Ability to give informed consent;
• Life expectancy greater than 6 months.

PD subjects:

• On peritoneal dialysis for greater than 3 months;
• Using glucose lactate-buffered PD solutions with consistent glucose exposure;
• Stable peritoneal prescription (Kt/V > 1.7 or Tccr > 50 ml/week/1.73 m2).

Control subjects:

• Estimated glomerular filtration rate (GFR) ≥ 60 ml/min/1.73m2;
• No proteinuria.

Exclusion Criteria (both subject groups):

• Pregnancy;
• Intolerance to study protocols;
• Severe, unstable, active, or chronic inflammatory disease (congestive heart failure-NY Class IV, active infection, active connective tissue disorder, active cancer or cancer history in the prior 5 years, HIV, liver disease, including active chronic hepatitis B or C);
• Active inflammatory conditions [systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), minimal change disease (MCD)];
• Patients prescribed or being treated with spironolactone;
• History of cirrhosis;
• Poor compliance with dialysis prescription.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Controls
PD subjects

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Aim 1: Na+ stores in PD subjects vs. controls	baseline
Aim 2: a change in Na+ stores in PD subjects	baseline and 2 years

Collaborators and Investigators

• Sponsor: Vanderbilt University Medical Center
• Collaborators: Baxter Healthcare Corporation
• Investigators: Principal Investigator: Jens Titze, MD, Vanderbilt University

Study record dates

Study Major Dates

• Study Start: August 1, 2014
• Primary Completion (Actual): November 29, 2016
• Study Completion (Actual): November 29, 2016

Study Registration Dates

• First Submitted: August 6, 2014
• First Submitted That Met QC Criteria: August 7, 2014
• First Posted (Estimate): August 8, 2014

Study Record Updates

• Last Update Posted (Actual): October 3, 2019
• Last Update Submitted That Met QC Criteria: October 2, 2019
• Last Verified: October 1, 2019

More Information

Terms related to this study

• Keywords: Na+ MRI; salt stores
• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Renal Insufficiency; Renal Insufficiency, Chronic; Kidney Failure, Chronic
• Other Study ID Numbers: 140157