The purpose of this study is to measure the effect of omeprazole on intestinal calcium absorption in postmenopausal women. Because older adults frequently take PPI, it is critical to understand the impact of PPI therapy on calcium homeostasis. In this study, I hypothesize that PPI therapy does not alter intestinal calcium absorption in postmenopausal women...
Date First Received: December 19, 2007
Last Updated: June 2, 2008
Verified by: University of Wisconsin, Madison, June 2008
Clinical Trial Phase: Phase 4 | Start Date: January 2008
Overall Status: Active, not recruiting
Estimated Enrollment: 20
Brief Summary
Official Title: “Does Omeprazole Decrease Intestinal Calcium Absorption?”
Condition Keyword(s):
Intervention(s):
The purpose of this study is to measure the effect of omeprazole on intestinal calcium absorption in postmenopausal women. Because older adults frequently take PPI, it is critical to understand the impact of PPI therapy on calcium homeostasis. In this study, I hypothesize that PPI therapy does not alter intestinal calcium absorption in postmenopausal women.
Study Type: Interventional
Study Design: Other, Non-Randomized, Open Label, Single Group Assignment
Study Primary Completion Date: December 2008
Detailed Clinical Trial Description
Existing literature makes it unclear whether PPI therapy truly decreases intestinal calcium absorption. Up to 25 postmenopausal women will participate in this two-month study. The primary study outcome is the change in intestinal calcium absorption following omeprazole therapy. The secondary outcomes include the change in urine n-telopeptide, the month-to-month variability in intestinal calcium absorption and the establishment of a DNA bank for genetic studies of calcium homeostasis.
We will interview women and review their medical records to determine eligibility. Eligible subjects will undergo three GCRC studies. The first 2 studies will determine the monthly variation in calcium absorption, while the 3rd study will occur after taking 40 mg of omeprazole daily for 30 days. Women will present to the GCRC in the early morning and receive an oral and intravenous calcium tracer with breakfast. Over the next 24 hours, we will collect all urine for measurement of its calcium content. During the first or second GCRC stay, we will measure each subject's gastric pH by collecting gastric fluid from a temporary nasogastric tube. In consenting subjects we will collect one tube of blood, isolate its DNA and save it indefinitely within the locked GRECC Drezner Laboratory (5th Floor, VA Hospital) permitting future genetic studies related to calcium homeostasis.
Intervention(s) in this Clinical Trial
- Drug: Omeprazole
- 40 mg po qAM one-half hour before breakfast for 30 days
Arms, Groups and Cohorts in this Clinical Trial
- Experimental: Experimental
- Subjects will receive omeprazole 40 mg daily for 30 days
Outcome Measures for this Clinical Trial
Primary Measures
- Change in intestinal calcium absorption after one month of omeprazole therapy
- Time Frame: 2 months
Safety Issue?: Yes
- Time Frame: 2 months
Secondary Measures
- The change in bone resorption (urine n-telopeptide) after one month of omeprazole therapy and the month-to-month variability in intestinal calcium absorption.
- Time Frame: 2 months
Safety Issue?: Yes
- Time Frame: 2 months
Criteria for Participation in this Clinical Trial
Inclusion Criteria:
- Women at least 5 years past menopause, defined as the last date of menses
Exclusion Criteria:
- Allergy/Intolerance to orange juice
- Allergy/Intolerance to omeprazole or other PPI therapy
- Use of drugs that interact with omeprazole including oral anti-fungal agents, coumadin, diazepam, phenytoin & tacrolimus
- Use of antacids, PPI or H2-blocker therapy within the past two months
- Intestinal conditions associated with malabsorption or low gastric acid levels including Crohn's Disease, ulcerative colitis, pernicious anemia, bacterial overgrowth, celiac sprue, chronic diarrhea or use of antibiotics within the past month
- Known Stage 4 or 5 Chronic Kidney Disease, defined as an estimated GFR <30 cc/minute
- Use of medications known to interfere with calcium metabolism, including oral steroids or anticonvulsants
Gender Eligibility for this Clinical Trial: Female
Minimum Age for this Clinical Trial: N/A
Maximum Age for this Clinical Trial: N/A
Are Healthy Volunteers Accepted for this Clinical Trial?: Accepts Healthy Volunteers
Clinical Trial Sponsor Information
Lead Sponsor: University of Wisconsin, Madison
Overall Clinical Trial Officials and Contacts
Karen E Hansen, MD Principal Investigator Univeristy of Wisconsin School of Medicine and Public Health
Related Publications
References
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Additional Information
Information obtained from ClinicalTrials.gov on September 05, 2008
Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00582972
Study ID Number: H-2007-0179
ClinicalTrials.gov Identifier: NCT00582972
Health Authority: United States: Institutional Review Board
Clinical Trials Authorship and Review
Clinical Trials content is provided directly by the U.S. National Institutes of Health via ClinicalTrials.gov and is not reviewed separately by ClinicalTrialsFeeds.org. Every page of specific clinical trials information contains a unique identifier which can be used to find further details directly from the National Institutes of Health.
