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Trial registered on ANZCTR


Trial ID
ACTRN12614000865617
Ethics application status
Approved
Date submitted
5/08/2014
Date registered
13/08/2014
Date last updated
13/08/2014
Type of registration
Retrospectively registered

Titles & IDs
Public title
A randomised cross-over trial to examine the effects of calcium citrate on blood calcium levels, blood coagulation and blood pressure in normal postmenopausal women
Scientific title
In healthy postmenopausal women, what are the effects of calcium citrate compared with a placebo on serum calcium, blood pressure and blood coagulation?
Secondary ID [1] 285108 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cardiovascular disease 292660 0
Condition category
Condition code
Diet and Nutrition 292975 292975 0 0
Other diet and nutrition disorders
Cardiovascular 292976 292976 0 0
Hypertension
Cardiovascular 292977 292977 0 0
Diseases of the vasculature and circulation including the lymphatic system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
A single dose of 1 g of calcium as citrate as an oral tablet. There will be a 6 day wash out period between interventions.
Intervention code [1] 289958 0
Prevention
Comparator / control treatment
A single dose of a placebo containing no calcium as an oral microcellulose tablet. There will be a 6 day day wash out period between interventions.
Control group
Placebo

Outcomes
Primary outcome [1] 292832 0
Change in R-time (time to clot initiation) as measured by thromboelastography using a Thromboelastograph (Haemoscope, Stokie, IL)
Timepoint [1] 292832 0
2, 4, 6 hours after each intervention is ingested
Primary outcome [2] 292833 0
Change in other measures of blood coagulation (K-time, alpha angle, maximum ampltiude and coagulation index) as measured by thromboelastography using a Thromboelastograph (Haemoscope, Stokie, IL)
Timepoint [2] 292833 0
2, 4 and 6 hours after each intervention is ingested
Primary outcome [3] 292834 0
Change in systolic and diastolic blood pressure as measured by an automatic sphygmomanometer
Timepoint [3] 292834 0
2, 4 and 6 hours after each intervention is ingested
Secondary outcome [1] 309771 0
Change in serum ionised and total calcium as measured by serum assay
Timepoint [1] 309771 0
2, 4 and 6 hours after each intervention is ingested

Eligibility
Key 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 women).
Minimum age
No limit
Maximum age
No limit
Gender
Females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Current smoker, current use of Warfarin, aspirin or other blood thinning medications, diabetes, current use of blood pressure medication, past history of coronary heart disease, cerebrovascular disease or peripheral vascular disease, 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, calcium supplements: those consistently using 500 mg/day or more need to be off calcium supplements for 6 months before entering the study; doses <100 mg/day can be continued during the study; doses between 100 and 499 mg/day require intermediate times of withdrawal prior to study entry, 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, calciferol supplements > 2000 IU/day (lower doses can be continued during the study).

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Safety
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 6275 0
New Zealand
State/province [1] 6275 0

Funding & Sponsors
Funding source category [1] 289715 0
Government body
Name [1] 289715 0
Health Research Council
Address [1] 289715 0
PO Box 5541
Wellesley Street
Auckland
1141
Country [1] 289715 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
Faculty of Medical and Health Sciences
University of Auckland
Private Bag 92019
Auckland 1142
New Zealand
Country
New Zealand
Secondary sponsor category [1] 288409 0
None
Name [1] 288409 0
Address [1] 288409 0
Country [1] 288409 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 291453 0
Health and Disabilities Ethics Committees
Ethics committee address [1] 291453 0
Ministry of Health
1 the Terrace
PO Box 5013
Wellington 6145
Ethics committee country [1] 291453 0
New Zealand
Date submitted for ethics approval [1] 291453 0
Approval date [1] 291453 0
04/09/2013
Ethics approval number [1] 291453 0

Summary
Brief summary
The objective of this study is to determine whether calcium supplements acutely influence blood pressure and blood coagulation. This is a randomised, double-blind, placebo-controlled, cross-over trial. Participants will be 40 healthy postmenopausal women. Participants will attend two visits at our research clinic where they will receive 1 g of calcium as citrate or a placebo containing no calcium. Visits will be separated by at least 6 days. Blood will be sampled and blood pressure measured prior to, and 2, 4 and 6 hours after each intervention is ingested. Blood coagulation will be measured at each time-point by thromboelastography.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 50474 0
Prof Ian Reid
Address 50474 0
Faculty of Medical and Health Sciences
University of Auckland
Private Bag 92019
Auckland 1142
Country 50474 0
New Zealand
Phone 50474 0
+64 9 3737 599 ext 86259
Fax 50474 0
Email 50474 0
i.reid@auckland.ac.nz
Contact person for public queries
Name 50475 0
Miss Sarah Bristow
Address 50475 0
Faculty of Medical and Health Sciences
University of Auckland
Private Bag 92019
Auckland 1142
Country 50475 0
New Zealand
Phone 50475 0
+64 9 923 3773
Fax 50475 0
Email 50475 0
s.bristow@auckland.ac.nz
Contact person for scientific queries
Name 50476 0
Miss Sarah Bristow
Address 50476 0
Faculty of Medical and Health Sciences
University of Auckland
Private Bag 92019
Auckland 1142
Country 50476 0
New Zealand
Phone 50476 0
+64 9 923 3773
Fax 50476 0
Email 50476 0
s.bristow@auckland.ac.nz