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

Purpose

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.

Condition	Intervention
End-Stage Renal Disease	Procedure: exposure to a high-calcium dialysate bath

MedlinePlus related topics:

Dialysis Kidney Failure

ChemIDplus related topics:

Parathyroid Calcium gluconate Phosphorus

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Basic Science, Non-Randomized, Open Label, Crossover Assignment

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

Further study details as provided by University of Kansas:

Primary Outcome Measures:

change in serum fibroblast growth factor-23 (FGF-23) [ Time Frame: 0, 45, 90, and 150 minutes ] [ Designated as safety issue: No ]

Estimated Enrollment:	30
Study Start Date:	January 2007
Estimated Study Completion Date:	June 2009
Estimated Primary Completion Date:	June 2009 (Final data collection date for primary outcome measure)

Arms

Assigned Interventions

1: Experimental

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.

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).

Eligibility

Ages Eligible for Study:	18 Years and older
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

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

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00477516

Locations


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

Sponsors and Collaborators

University of Kansas

Investigators


Principal Investigator:	Peter W. Santos, D.O	University of Kansas

Principal Investigator:	James B. Wetmore, M.D.	University of Kansas

More Information

Responsible Party:	University of Kansas Medical Center ( James B. Wetmore, MD )
Study ID Numbers:	10571
First Received:	May 21, 2007
Last Updated:	September 16, 2008
ClinicalTrials.gov Identifier:	NCT00477516
Health Authority:	United States: Institutional Review Board

Study placed in the following topic categories:

Renal Insufficiency

Urologic Diseases

Renal Insufficiency, Chronic

Kidney Failure, Chronic

Kidney Diseases

Kidney Failure

Inflammation

ClinicalTrials.gov processed this record on October 10, 2008

Sponsored by:	University of Kansas
Information provided by:	University of Kansas
ClinicalTrials.gov Identifier:	NCT00477516