Analysis of Calcium Balance in Chronic Kidney Disease

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
University of Colorado, Denver
ClinicalTrials.gov Identifier:
NCT00974532
First received: June 3, 2009
Last updated: December 3, 2012
Last verified: September 2009
  Purpose

Subjects with normal kidney function are able to excrete in their urine the calcium and phosphorus absorbed via the gastrointestinal tract and are thereby are able to maintain calcium and phosphorus balance. Patients with chronic kidney disease often have normal blood levels of calcium and phosphorus but no research has been conducted to determine if they are able to excrete their daily intake of these minerals. If they are not able to excrete their daily intake, these minerals could be deposited in soft tissue and blood vessels and contribute to the increased risk of cardiovascular disease seen in patients with chronic kidney disease. This study will determine if subjects with chronic kidney disease are in balance primarily with regard to calcium and at what level of kidney function they are no longer able to maintain balance. Understanding whether patients with chronic kidney disease are in balance will help direct future therapeutic interventions.


Condition Intervention
Chronic Kidney Disease
Dietary Supplement: High calcium diet 2000 mg/day
Dietary Supplement: Low calcium diet, 800 mg/day

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Bio-availability Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Investigator)
Primary Purpose: Prevention
Official Title: Analysis of Calcium Balance in Chronic Kidney Disease

Resource links provided by NLM:


Further study details as provided by University of Colorado, Denver:

Primary Outcome Measures:
  • Calcium balance [ Time Frame: 48 hour ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Phosphorus balance [ Time Frame: 48 hours ] [ Designated as safety issue: No ]
  • PTH [ Time Frame: 2 WEEKS ] [ Designated as safety issue: No ]
  • FGF-23 [ Time Frame: 2 WEEKS ] [ Designated as safety issue: No ]

Enrollment: 16
Study Start Date: May 2008
Study Completion Date: February 2012
Primary Completion Date: February 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Subjects with normal kidney function
eGFR > 60 ml/min/m²
Dietary Supplement: High calcium diet 2000 mg/day
High calcium (2000 mg elemental calcium) diet x 9 days
Dietary Supplement: Low calcium diet, 800 mg/day
Low calcium (800 mg elemental calcium) diet x 9 days
Experimental: CKD late Stage 3 and Stage 4
eGFR 15-40 ml/min/m²
Dietary Supplement: High calcium diet 2000 mg/day
High calcium (2000 mg elemental calcium) diet x 9 days
Dietary Supplement: Low calcium diet, 800 mg/day
Low calcium (800 mg elemental calcium) diet x 9 days

  Show Detailed Description

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Men and women 18 years of age or greater and able to comply with the study protocol.
  • eGFR within appropriate target ranges (15-40 ml/min/m² for late stage CKD stage 3 stage 4, and eGFR > 60 ml/min/m² for normal subjects)
  • Stable kidney function defined as an eGFR which remains within a 10ml/min range over a 3 to 6 month period prior to study enrollment. This will be determined from historical laboratory data.
  • Willing to follow study protocol
  • Have a level of understanding and willingness to cooperate with all visits and procedures as described by the study personnel
  • Overall stable medical condition, defined as no malignancy, metabolic condition or gastrointestinal condition that would make it difficult to comply with the study protocol and complete both dietary study periods
  • Able to read the consent form and provide informed consent.
  • Serum calcium and phosphorus within the normal range off of vitamin D analogues, calcium supplements, and phosphate binders for 1 month.

Exclusion Criteria:

  • 1. Age less than 18 years
  • Are pregnant, plan on becoming pregnant during the study period, or breast-feeding, if female.
  • Patient declines participation.
  • GI malabsorption, short bowel syndrome, frequent vomiting, or gastroparesis.
  • Subject receiving synthetic parathyroid hormone, glucocorticoids, calcitonin or bisphosphonates.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00974532

Locations
United States, Colorado
University of Colorado Denver Health Sciences Center
Denver, Colorado, United States, 80045
Sponsors and Collaborators
University of Colorado, Denver
  More Information

Publications:
Responsible Party: University of Colorado, Denver
ClinicalTrials.gov Identifier: NCT00974532     History of Changes
Other Study ID Numbers: 07-0959, G195
Study First Received: June 3, 2009
Last Updated: December 3, 2012
Health Authority: United States: Institutional Review Board

Keywords provided by University of Colorado, Denver:
balance
chronic kidney disease
calcium
phosphorus

Additional relevant MeSH terms:
Kidney Diseases
Renal Insufficiency, Chronic
Kidney Failure, Chronic
Urologic Diseases
Renal Insufficiency
Calcium, Dietary
Bone Density Conservation Agents
Physiological Effects of Drugs
Pharmacologic Actions

ClinicalTrials.gov processed this record on April 17, 2014