Association of FGF-23 and Parathyroid Hormone (PTH) in Dialysis Patients

June 13, 2012 updated by: James B. Wetmore, MD

Determination of FDF-23 Levels in Non-suppressible PTH Secretion and the Influence of Inflammation on Fetuin A Levels During Hemodialysis Treatment

The purpose of this study is to determine how levels of this newly-discovered hormone, called FGF-23, changes in the blood in response to a high calcium dialysis bath during a hemodialysis (HD) treatment, and how this relates to changes in the calcium and PTH levels. We are also studying the effects of dialysis and inflammation on the levels of Fetuin A.

We intend to prospectively study a cohort of end stage renal disease (ESRD) patients on hemodialysis in order to determine whether FDF-23 levels independently affect non-suppressible PTH levels. The relationship between Fetuin A and inflammatory markers will also be determined. By dialyzing patients on 3.5 mEq/L calcium dialysate bath, we seek any relationship between ionized calcium, FGF-23 and PTH.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The goal of this study is to ascertain whether there is a regulatory relationship between the novel phosphorus-regulating polypeptide fibroblast growth factor-23 (FGF-23), ionized calcium (iCa), and parathyroid hormone (PTH) levels. In addition, we will determine if there is an inverse relationship between Fetuin A levels and inflammatory markers, interleukin 6 (IL-6) and C-reactive protein (CRP), during a hemodialysis treatment.

All patients participating in this study will be off Zemplar and/or Sensipar for a washout period of approximately 4 weeks as these medications will interfere with the study. Patients will go through one designated research hemodialysis time for a blood draw. Blood draws will be taken during 4 separate intervals at 0, 45, 90 and 150 minutes. At each interval, 4 tubes of blood will be drawn.

There are no further required blood draws once each designated research HD session has been completed. At the conclusion of the designated research HD session, vitamin D analogue (Zemplar®) and/or Cinacalcet (Sensipar®) will be restarted, and the dose will be adjusted to reflect the subject's recent biochemical markers (Ca, Phos, and iPTH).

Study Type

Interventional

Enrollment (Actual)

18

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Kansas
      • Kansas City, Kansas, United States, 66160
        • University of Kansas Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • 18 years or older
  • Chronic Hemodialysis for more than 3 months
  • iPTH levels ≥ 300 pg/ml in the absence of therapy: Cinacalcet (Sensipar ®) and/or 1,25 Vitamin analogues (Zemplar®)
  • Corrected Ca ≥ 8.4 mg/dl at time of enrollment
  • Ability to stay at least 3 hours during hemodialysis treatment

Exclusion Criteria:

  • Pediatric Patients (age ≤ 18 years)
  • Those unable to give informed consent
  • Dialysis treatment for less than 3 months, or pre-emptive kidney transplantation
  • Inability to stay more than 3 hours during a single hemodialysis treatment period

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Interventional Model: Crossover Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 1
Procedure: exposure to a high-calcium dialysate bath
Subjects are exposed to a high calcium (3.5 mEq/L) dialysate bath for 150 minutes (part 1). At defined timepoints (0, 45, 90, and 150 min) blood is sampled for calcium, PTH, phosphorous, and FGF-23. At another (later) dialysis session (part 2), the process is repeated except that the subjects are exposed to a normal calcium bath (2.5 mEq/L). For each subject, results from part 1 are compared to the results from part 2.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
change in serum fibroblast growth factor-23 (FGF-23)
Time Frame: 0, 45, 90, and 150 minutes
0, 45, 90, and 150 minutes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

James B. Wetmore, MD

Investigators

  • Principal Investigator: Peter W. Santos, D.O, University of Kansas Medical Center
  • Principal Investigator: James B. Wetmore, M.D., University of Kansas Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

January 1, 2007

Primary Completion (Actual)

August 1, 2007

Study Completion (Actual)

August 1, 2007

Study Registration Dates

First Submitted

May 21, 2007

First Submitted That Met QC Criteria

May 22, 2007

First Posted (Estimate)

May 23, 2007

Study Record Updates

Last Update Posted (Estimate)

June 15, 2012

Last Update Submitted That Met QC Criteria

June 13, 2012

Last Verified

June 1, 2012

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 10571

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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