Calcium Supplements Strategy for Kidney Stones Prevention in Crohn's Patients

This study is currently recruiting participants. (see Contacts and Locations)
Verified December 2015 by University of British Columbia
University of Texas Southwestern Medical Center
Information provided by (Responsible Party):
University of British Columbia Identifier:
First received: November 22, 2012
Last updated: December 10, 2015
Last verified: December 2015
Hospitalization for kidney stones in the Inflammatory Bowel Disease (IBD) population is common, particularly among Crohn's patients who had a small bowel resection. This patient population experiences a lifetime occurrence of kidney stone formation as high as 25% accompanied with a high rate of recurrence (the typical rate of stone formation is ~10% in the non IBD population). Giving oral calcium is used to bind oxalate in the intestine in an attempt to reduce the amount of oxalate that is absorbed into the body and to reduce urinary oxalate levels. However, there are no defined guidelines for the optimum dosing of calcium. This study's primary objective is to scientifically define an appropriate range of calcium supplementation that reduce the level of oxalate found in the urine of patients living with inflammatory bowel disease.

Condition Intervention
Kidney Calculi
Crohn's Disease
Dietary Supplement: Calcium Carbonate

Study Type: Interventional
Study Design: Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Prevention
Official Title: Oral Calcium Supplementation, a Strategy to Reduce Kidney Stones in Crohn's Patients Living With a Small Bowel Resection

Resource links provided by NLM:

Further study details as provided by University of British Columbia:

Primary Outcome Measures:
  • Molar ratio of urinary calcium:oxalate in relation to the supersaturation product of calcium oxalate [ Time Frame: 7 days ] [ Designated as safety issue: No ]

    Molar ratio of urinary calcium:oxalate in relation to the supersaturation product of calcium oxalate will be calculated from the 24-hour urine test.

    The patient will take dietary calcium for 7 days and then we will evaluate their urine chemistry. Additionally, 24-hour urine collections are considered the standard for urinalysis in comparison to spot urine chemistry. The initial data, prior to calcium supplementation, will serve as the control, providing the patient's baseline risk for kidney stone formation.

Secondary Outcome Measures:
  • Optimal level of Ca supplementation for prevention of stones in Crohn's patients [ Time Frame: 7 days ] [ Designated as safety issue: No ]
    Practical guidelines for physicians managing Crohn's patients will be developed based on the optimal Ca supplement dosages and determine the optimal level of calcium supplementation in each patient, based on urinary parameters from 24-hour urine.

Estimated Enrollment: 40
Study Start Date: December 2012
Estimated Study Completion Date: December 2017
Estimated Primary Completion Date: December 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Dietary supplement
Calcium Carbonate
Dietary Supplement: Calcium Carbonate
There is a regimen for dietary supplement intake that will be provided to study participants.
Other Name: CaCO3

Detailed Description:
The primary objective of this study is to establish optimal oral calcium supplementation in Crohn's patients who have had an ileal bowel resection. This population is at high risk for calcium oxalate kidney stones, a direct consequence of extensive gut malabsorption and enteric hyperoxaluria. The benefit of providing oral calcium in this patient population (as a means to reduce intestinal oxalate absorption) is known, however, there are no appropriate targets for calcium dosing, which is presently performed empirically or not at all. Our goal is to establish simple, safe and practical guidelines for calcium supplementation.

Ages Eligible for Study:   19 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. a pathologically confirmed diagnosis of Crohn's disease
  2. prior ileal resection with an intact colon (surgery>6 months preceding involvement in study)
  3. hyperoxaluria (defined as> 48 mg (>0.5 mmol) per 24 hour urine samples.

    • Patients will not be excluded if they are known kidney stone formers.

Exclusion Criteria:

  1. current pregnancy
  2. patient's without baseline hyperoxaluria (defined as >48 mg or 0.5mmol per 24 hour urine samples)
  3. patients in renal failure assessed by a GFR < 60
  4. inability to provide informed consent
  5. active cancer
  6. hyperparathyroidism
  7. hyperphosphatemia
  8. <19 years of age
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01735461

Contact: Olga Arsovska 6048754111 ext 62421

Canada, British Columbia
Vancouver General Hospital Recruiting
Vancouver, British Columbia, Canada, V5Z1M9
Principal Investigator: Ben Chew, MD         
Sub-Investigator: Ryan Paterson, MD         
Sponsors and Collaborators
University of British Columbia
University of Texas Southwestern Medical Center
Principal Investigator: Ben Chew, MD University of British Columbia
  More Information

Responsible Party: University of British Columbia Identifier: NCT01735461     History of Changes
Other Study ID Numbers: H11-02525 
Study First Received: November 22, 2012
Last Updated: December 10, 2015
Health Authority: Canada: Health Canada

Additional relevant MeSH terms:
Crohn Disease
Kidney Calculi
Digestive System Diseases
Gastrointestinal Diseases
Inflammatory Bowel Diseases
Intestinal Diseases
Kidney Diseases
Pathological Conditions, Anatomical
Urinary Calculi
Urologic Diseases
Calcium Carbonate
Calcium, Dietary
Bone Density Conservation Agents
Gastrointestinal Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs processed this record on May 26, 2016