Calcium Absorption in Postmenopausal Thai Women

Completed

• Conditions: Fractional Calcium Absorption

• Registration Number: NCT02291315
• Lead Sponsor: Cornell University

Brief Summary

Adequate calcium absorption is essential for reducing one's risk of developing osteoporosis. However, postmenopausal Thai women consume diets which are habitually low in calcium due to lactose intolerance and dietary patterns which typically do not include milk-based products. The primary goal of this study is to measure the fractional calcium absorption from milk and a commonly ingested green leafy vegetable (cassia) in postmenopausal Thai women with habitually low calcium intakes. The secondary objective is to determine associations between calcium absorption and biomarkers which impact vitamin D status and bone metabolism.

Detailed Description

Postmenopausal Thai women (n=22) will be recruited from the community surrounding Bangkok and Nakhon Pathon, Thailand. They will be invited to participate in an isotope study comparing the fractional calcium absorption from milk and cassia. Upon arrival, a fasting blood sample will be drawn on the morning of the absorption study to analyze serum markers of vitamin D and bone metabolism (25-hydroxy vitamin D \[25OHD\], parathyroid hormone \[PTH\], and beta-crossLaps) and to determine their impact on calcium absorption. Following this blood draw, women will receive a stable calcium isotope (42Ca) intravenously. Then for breakfast and lunch respectively, the women will be randomly assigned to orally ingest a stable calcium isotope from either the milk (44Ca) or cassia (43Ca) test meals. On day two, women will receive a breakfast, snack, and lunch meal. Urine samples will be collected over the entire 28 hour period and the 24-hr urine collection will be used to measure urinary calcium concentration and to calculate fractional calcium absorption.

Study Timeline

• Study Start: 2007-07
• Primary Completion: 2007-09
• Study Completion: 2007-09
• Status Verified: 2014-11
• Study First Submitted: 2014-11-10
• Study First Submitted QC: 2014-11-12
• Last Update Submitted: 2014-11-12
• Study First Posted: 2014-11-14
• Last Update Posted: 2014-11-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 22

Inclusion Criteria

• Healthy
• At least 3 years postmenopausal

Exclusion Criteria

• Diagnosed gastrointestinal or metabolic diseases known to interfere with calcium absorption and metabolism
• Women taking medications (including thiazide diuretics, hormonal replacement therapy, etc.) within two months prior to the study
• Women taking dietary supplements within two months prior to the study

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Fractional calcium absorption	24 hours after the ingestion of the second test meal	Urine samples will be collected over s 28 hour period post-dosing with collection ending 24 hours after the ingestion of the second test meal.

Secondary Outcome Measures

Name	Time	Method
The concentration of 25-hydroxy vitamin D (25OHD) in serum	Upon entry to the study, a 10 mL blood sample will be collected in a less than 2 hour time period.	A fasting 10 mL blood sample will be collected upon entry into the study and used for determining the concentration of 25OHD in serum.
The concentration of parathyroid hormone (PTH) in serum	Upon entry to the study, a 10 mL blood sample will be collected in a less than 2 hour time period.	A fasting 10 mL blood sample will be collected upon entry into the study and used for determining the concentration of PTH in serum.
The concentration of beta-crossLaps in serum	Upon entry to the study, a 10 mL blood sample will be collected in a less than 2 hour time period.	A fasting 10 mL blood sample will be collected upon entry into the study and used for determining the concentration of beta-crossLaps in serum.

Trial Locations

Locations (1)

Human Metabolic Research Unit; 🇺🇸 Ithaca, New York, United States