A Randomised Control Trial to Compare the Effects of Hydroxyapatite Preparations, Calcium Citrate and Calcium Carbonate on Serum Calcium and Markers of Bone Turnover in Healthy Postmenopausal Women.

In healthy postmenopausal women what are the effects of hydroxyapatite preparations compared with calcium citrate and calcium carbonate on serum calcium and markers of bone turnover?

Status

Completed

Phases

Unknown

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12611000232932

Enrollment

100

Registered

2011-03-03

Start date

2011-07-01

Completion date

2012-05-17

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This is a randomised, single-blind, controlled 3-month study. One hundred healthy postmenopausal women will be randomised to one of the following five supplement preparations: 1g calcium as one of 2 hydroxyapatite preparations, 1g of calcium as citrate, 1g calcium as carbonate or a placebo. Participants will be seen twice over 3 months for clinical evaluation and laboratory, blood pressure and bone density measurement. Measurements will include serum biochemistry, haematology, markers of bone turnover and vascular calcification, and blood coagulation indices. The co-primary endpoints will be changes in blood calcium following the first dose of calcium, and markers of bone turnover at 3 months.

Interventions

There will be five intervention arms as follows: Arm 1: 1g of calcium as citrate Arm 2: 1g of calcium as carbonate Arm 3: 1g of calcium as hydroxyapatite preparation A* Arm 4: 1g of calcium as hydroxyapatite preparation B* Arm 5: placebo containing no calcium (microcrystalline cellulose) * Process manipulations will result in two preparation variants that will differ in their particle density and size distribution, food chemistry (moisture, fat, protein, ash) ratios and the extent of enzyme hydrolysis The mode of administration is by oral capsule, with 8 capsules providing 1g of calcium. On day 1, each preparation will be taken in a single dose of eight capslues . For the remainder of the trial period, the trial medications will be taken in two divided doses daily, four capsules in the morning and four in the evening. The duration of administration is 12 weeks.

Study design

Allocation

Randomised controlled trial

Intervention model

Parallel

Primary purpose

Prevention

Masking

Blinded (masking used)

Eligibility

Sex/Gender

All

Age

0 to No maximum

Healthy volunteers

Yes

Inclusion criteria

Female, postmenopausal 5 years or more (menopause defined as at least 12 months since last period in a woman aged > 45 yrs with intact uterus, or serum oestradiol < 100 pmol/l with FSH > 50 IU/l in younger or hysterectomised woman).

Exclusion criteria

Past history of coronary heart disease, cerebrovascular disease or peripheral vascular disease, estimated 5-year cardiovascular risk >15%, renal impairment (serum creatinine >0.15 mmol/L), chronic liver disease, untreated hypothyroidism or hyperthyroidism, concurrent major systemic illness (including malignancy), active major gastrointestinal disease, metabolic bone diseases, or serum ALP >normal, primary hyperparathyroidism, current or expected use of oral glucocorticoid drugs during the trial period, current or past use of bisphosphonate therapy in the preceding 2 years, use of hormone replacement therapy within the last 12 months, use of other medication known to cause osteoporosis or interfere with bone metabolism.

Outcome results