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

End-Stage Renal Disease Clinical Trial

Official title:

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

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00477516
• Other study ID #: 10571
• Status: Completed
• Phase: N/A
• First received: May 21, 2007
• Last updated: June 13, 2012
• Start date: January 2007
• Est. completion date: August 2007

Study information

• Verified date: June 2012
• Source: University of Kansas Medical Center
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

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.

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).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 18
• Est. completion date: August 2007
• Est. primary completion date: August 2007
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

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 Design

Intervention Model: Crossover Assignment, Masking: Open Label, Primary Purpose: Basic Science

Related Conditions & MeSH terms

• End-Stage Renal Disease
• Kidney Failure, Chronic

Intervention

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.

Locations

Country	Name	City	State
United States	University of Kansas Medical Center	Kansas City	Kansas

Sponsors (1)

Lead Sponsor	Collaborator
James B. Wetmore, MD

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	change in serum fibroblast growth factor-23 (FGF-23)		0, 45, 90, and 150 minutes	No