Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12605000017628
Ethics application status
Approved
Date submitted
18/07/2005
Date registered
18/07/2005
Date last updated
18/07/2005
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effect of Vitamin D Supplementation on Blood Pressure and Insulin Sensitivity
Scientific title
A randomised phase III study to evaluate the effects of Vitamin D supplementation on patients with low vitamin D levels to reduce blood pressure levels and improve insulin sensitivity
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Blood Pressure 79 0
Condition category
Condition code
Blood 97 97 0 0
Normal development and function of platelets and erythrocytes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
A randomised double-blind clinical trial of 100 ug daily doses of vitamin D3 versus placebo tablets.
Intervention code [1] 26 0
Prevention
Comparator / control treatment
Each participant will receive daily doses of vitamin D3 or placebo for 12 weeks
Control group
Placebo

Outcomes
Primary outcome [1] 123 0
Blood pressure
Timepoint [1] 123 0
Measured at baseline and at 12 weeks.
Secondary outcome [1] 286 0
Insulin sensitivity, as measured by a New Zealand developed index calculated from fasting blood levels of insulin and triglycerides.
Timepoint [1] 286 0

Eligibility
Key inclusion criteria
Aged >40 years (Tongan and Maori) and >65 years (European) 25OHD levels <50 nmol/L.
Minimum age
40 Years
Maximum age
Not stated
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Treated diabetes, treated hypertension, taking of vitamin D supplements (including cod liver oil); serum calcium level above 2.60 mmol/L, regular outdoor activities during the middle of day during the study period, recent high sun exposure (eg. holidays in the Pacific islands); or planned holidays to areas with high sun exposure during the study period.

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)
Central randomisationb and packaging of tablets in non-identifiable packets that are used in consecutive order.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation by computer software, no restriction
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Phase 3
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
7/07/2005
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
120
Accrual to date
Final
Recruitment outside Australia
Country [1] 124 0
New Zealand
State/province [1] 124 0

Funding & Sponsors
Funding source category [1] 133 0
University
Name [1] 133 0
University of Auckland
Country [1] 133 0
Australia
Primary sponsor type
University
Name
University of Auckland
Address
Country
Australia
Secondary sponsor category [1] 95 0
University
Name [1] 95 0
University of Auckland
Address [1] 95 0
Country [1] 95 0
Australia

Ethics approval
Ethics application status
Approved

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 36336 0
Address 36336 0
Country 36336 0
Phone 36336 0
Fax 36336 0
Email 36336 0
Contact person for public queries
Name 9215 0
Robert Scragg
Address 9215 0
Epidemiology and Biostatistics
School of Population Health
Tamaki Campus
University of Auckland
Private Bag 92019
Auckland 1
Country 9215 0
New Zealand
Phone 9215 0
+64 9 3737599 (Ext. 86336)
Fax 9215 0
Email 9215 0
r.scragg@auckland.ac.nz
Contact person for scientific queries
Name 143 0
Robert Scragg
Address 143 0
Epidemiology and Biostatistics
School of Population Health
University of Auckland
Tamaki Campus
Private Bag 92019
Auckland 1
Country 143 0
New Zealand
Phone 143 0
+64 9 3737599 (Ext. 86336)
Fax 143 0
Email 143 0
r.scragg@auckland.ac.nz

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.