Do Aromatase Inhibitors (AIs) Decrease Intestinal Calcium Absorption?

• Sponsor: University of Wisconsin, Madison (Other)
• Overall Status: Completed
• CT.gov ID: NCT00766532
• Collaborator: (none)
• Enrollment: 12
• Arm: 1
• Duration (Months): 21

Study Details

Study Description

Brief Summary

Research Question: Do Aromatase Inhibitors Decrease Intestinal Calcium Absorption?

Study Design: Postmenopausal women with early stage breast cancer initiating aromatase inhibitor adjuvant therapy will participate in this two-month study. The primary study outcome is the change in intestinal calcium absorption following such therapy. Secondary outcomes are the changes in bone resorption markers and musculoskeletal signs and symptoms after initiation of therapy.

We will interview women and review their medical records to determine eligibility. Eligible subjects will undergo two calcium absorption studies. The first study will determine their baseline calcium absorption, and the second study will occur after taking an aromatase inhibitor daily for at least 6 weeks. Women will present to the research unit in the early morning and receive an oral and intravenous stable calcium tracer with breakfast. Over the next 24 hours, we will collect all urine for measurement of its calcium content. During each inpatient stay, we will assess musculoskeletal symptoms by questionnaire and joint examination. Each woman will complete a four-day diet diary twice during the study.

Condition or Disease	Intervention/Treatment	Phase
Breast Cancer; Osteoporosis; Osteopenia; Fracture	Drug: Aromatase Inhibitor	Phase 4

Study Design

• Study Type: Interventional
• Actual Enrollment: 12 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Diagnostic
• Official Title: Do Aromatase Inhibitors (AIs) Decrease Intestinal Calcium Absorption?
• Study Start Date: Jan 1, 2009
• Actual Primary Completion Date: Oct 1, 2010
• Actual Study Completion Date: Oct 1, 2010

Arms and Interventions

Arm	Intervention/Treatment
Experimental: aromatase inhibitor therapy aromatase inhibitor therapy for six weeks	Drug: Aromatase Inhibitor; Any aromatase inhibitor started as initial adjuvant therapy

Outcome Measures

Primary Outcome Measures

1. Change in Intestinal Calcium Absorption Related to Aromatase Inhibitor Therapy [baseline and 6 weeks later]

   intestinal calcium absorption

Eligibility Criteria

Criteria

• Ages Eligible for Study: N/A and Older
• Sexes Eligible for Study: Female
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• Women at least 5 years past menopause, defined as date of last menses or bilateral oophorectomy

• Newly diagnosed breast cancer and starting an AI as initial adjuvant therapy

Exclusion Criteria

• Recent, current or planned chemotherapy for breast cancer, as this may have independent effects on intestinal health, calcium homeostasis and bone turnover

• Allergy or intolerance to orange juice, as one isotope is given with orange juice

• Current use of over-the-counter or prescription antacids, as they may influence Ca-Ab

• 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 or vitamin D metabolism, including oral steroids or anticonvulsants

• Significant lymphedema precluding adequate intravenous access

Contacts and Locations

Locations

No locations specified.

Sponsors and Collaborators

• University of Wisconsin, Madison

Investigators

• Principal Investigator: Karen E Hansen, MD, University of Wisconsin, Madison

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: University of Wisconsin, Madison
• ClinicalTrials.gov Identifier: NCT00766532
• Other Study ID Numbers: H-2008-0144
• First Posted: Oct 6, 2008
• Last Update Posted: Sep 14, 2012
• Last Verified: Sep 1, 2012

• Additional relevant MeSH terms: Osteoporosis; Bone Diseases, Metabolic; Aromatase Inhibitors

Study Results

Participant Flow

Recruitment Details	Postmenopausal women with early stage breast cancer and planning to start aromatase inhibitor therapy.
Pre-assignment Detail	Participants completed a four-day food diary

Arm/Group Title	Arm Title- Aromatase Inhibitor Therapy
Arm/Group Description	calcium absorption was measured among subjects at baseline and after taking aromatase inhibitor therapy.
Period Title: Overall Study
STARTED	12
COMPLETED	10
NOT COMPLETED	2

Baseline Characteristics

Arm/Group Title	Group 1
Arm/Group Description
Overall Participants	12
Age (Count of Participants)
<=18 years	0 0%
Between 18 and 65 years	6 50%
>=65 years	6 50%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	66 (7)
Sex: Female, Male (Count of Participants)
Female	12 100%
Male	0 0%
Region of Enrollment (participants) [Number]
United States	12 100%

Outcome Measures

1. Primary Outcome

Title	Change in Intestinal Calcium Absorption Related to Aromatase Inhibitor Therapy
Description	intestinal calcium absorption
Time Frame	baseline and 6 weeks later

Outcome Measure Data

Analysis Population Description

12 subjects provided informed consent but two dropped and did not undergo calcium absorption study visits. 10 subjects completed all calcium absorption study visits.

Arm/Group Title	Aromatase Inhibitor Therapy
Arm/Group Description
Measure Participants	10
Mean (Standard Deviation) [percent calcium absorption]	16 (6)

Adverse Events

Arm/Group Title	Group 1
Arm/Group Description
All Cause Mortality
	Group 1
	Affected / at Risk (%)	# Events
Total	/ (NaN)
Serious Adverse Events
	Group 1
	Affected / at Risk (%)	# Events
Total	0/10 (0%)
Other (Not Including Serious) Adverse Events
	Group 1
	Affected / at Risk (%)	# Events
Total	0/10 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.