ISRCTN ISRCTN20328039
DOI https://doi.org/10.1186/ISRCTN20328039
Secondary identifying numbers pRGF/075/08
Submission date
01/05/2008
Registration date
07/08/2008
Last edited
06/09/2013
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims:
Vitamin D is an unusual vitamin because for most people sunlight, not food, is the major source of the vitamin. It is well known that vitamin D is important for bones but recent research has linked vitamin D with other health outcomes, including heart health. This could have implications in the UK, because between the months of October and April, there is a lower strength of the type of sunlight we need to make vitamin D in the skin.
This study investigated whether giving daily vitamin D supplements could help reduce heart disease risk in postmenopausal women over one year.

Who can participate?
Healthy postmenopausal women aged between 60-70 years living in the Aberdeen area.

What does the study involve?
Participants were randomly allocated to receive either high or low dose vitamin D or placebo (dummy vitamin). Participants were asked to take one capsule every day with breakfast for 12 months. At each visit, study investigators collected a small blood sample to assess vitamin D status and a range of factors related to heart health. Participants were also asked to complete questionnaires on physical activity and habitual diet. Questions relating to general health, chronic pain, sun exposure and holidays abroad were also asked. After each visit, participants were asked to wear a small polysulphone film badge on the lapel on their outside coat or jacket for one week to measure sunlight exposure. At the beginning and end of the study, the participants’ bone mineral density and body composition were measured.

What are the possible benefits and risks of participating?
There are no direct benefits other than the information that participants will receive from their GP about their bone health after the bone scan. There are minor risks associated with blood collection which include excessive bleeding, fainting or feeling light headed, haematoma (blood collecting under the skin), and infection (a slight risk any time the skin is broken). There is a minor radiation exposure from the bone scan (similar to background radiation in Aberdeen).

Where is the study run from?
University of Aberdeen, UK

When is the study starting and how long is it expected to run for?
The study started in September 2008 and ended in 2010

Who is funding the study?
Department of Health, UK
National Osteoporosis Society, UK

Who is the main contact?
Dr Helen M Macdonald
h.macdonald@abdn.ac.uk

Contact information

Dr Helen Macdonald
Scientific

Osteoporosis Research Unit
Health Sciences Building
University of Aberdeen
Foresterhill
Aberdeen
AB25 2ZD
United Kingdom

Phone +44 (0)1224 559001
Email h.macdonald@abdn.ac.uk

Study information

Study designRandomised double blind placebo controlled trial - single centre
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typeQuality of life
Participant information sheet Not available in web format, please use the contact details below to request a patient information sheet
Scientific titleEffect of one year vitamin D intervention on risk of cardiovascular disease: a randomised controlled trial at 57°N
Study acronymVICtORy
Study objectives1. Does supplementing the diet with high or low doses of oral vitamin D3 (25 µg [dietary recommendations in the United States of America] or 10 µg [United Kingdom reference nutrient intake for over 65 year olds, or individuals at risk of vitamin D deficiency] daily respectively) reduce cardiovascular disease (CVD) risk markers and insulin sensitivity?
2. Does supplementing the diet with high or low doses of oral vitamin D3 (25 µg or 10 µg daily respectively) raise vitamin D status equally in overweight and lean individuals, and does adipose tissue distribution influence vitamin D status?
Ethics approval(s)Approval has been sought from the National Health Service Ethics Committee (NHS REC): Grampian Local Research Ethics Committee. Submitted on 22nd April 2008 and a decision will be made on the 8th May 2008 (ref: 08/S0802/73).
Health condition(s) or problem(s) studiedVitamin D status, CVD risk, insulin sensitivity
InterventionThis is a randomised double blind placebo controlled trial with supplementation starting in January 2009, aiming to assess whether dietary supplementation with oral vitamin D3 (10 µg or 25 µg) daily for 12 months reduces cardiovascular risk and insulin sensitivity. This could influence policy making decisions regarding dietary guidelines and in particular help set reference nutrient intakes using non-bone health outcomes in the over 60s. As there is concern that for any given intake of dietary vitamin D the circulating 25(OH)D does not increase as expected in overweight individuals, we will determine whether distribution of adipose tissue influences the effectiveness of the intervention, which will help to identify 'at risk' individuals.

Study visits will be held at two monthly intervals for 12 months (eight visits in total). Participants will be randomised to receive placebo, 10 µg or 25 µg oral vitamin D3. We will use minimisation criteria for vitamin D receptor (VDR) genotype, apolipoprotein E (ApoE) genotype (which is known in our study cohort), overweight (greater than or less than 25 kg/m^2) and smoking, so that the groups will be equally matched.
Intervention typeSupplement
Primary outcome measureAll primary and secondary outcomes will be measured at each study visit, i.e. at baseline, 2-, 4-, 6-, 8-, 10- and 12-month visits. Adipose tissue distribution will be measured at pre- and post-supplementation visits only.

1. Blood samples will be analysed for total cholesterol, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B100, fasted serum glucose, non-esterified fatty acids, insulin, glucose, intercellular adhesion molecule-1 (ICAM-1), interleukin-6 (IL-6), high sensitivity C-Reactive Protein (hsCRP), 25(OH)D, and routine hypercalcaemia
2. Three blood pressure measurements will be taken at each visit (first discarded and mean result of the following two will be used using an OMRON705CP sphygmomanometer accredited by the British Heart Foundation
3. Fasted urine samples will be collected in a willing sub-group of women and stored for future analysis of bone turnover markers
4. Adipose tissue distribution will be measured pre- and post-supplementation by dual energy x-ray absorptiometry (iDXA) full body scan
Secondary outcome measuresAll primary and secondary outcomes will be measured at each study visit, i.e. at baseline, 2-, 4-, 6-, 8-, 10- and 12-month visits. Adipose tissue distribution will be measured at pre- and post-supplementation visits only.

1. Sunlight exposure will be assessed by a ultraviolet (UV) polysulphone film badge (3 cm in size) worn on the lapel of the outside coat or jacket for 7 days, which will monitor the amount of sunlight participants are getting in the following week
2. Diet will be assessed using a validated food frequency questionnaire to be completed at home
3. Physical activity level will be assessed using a validated physical activity questionnaire (which has already been used in other cohorts of post-menopausal women) to be completed at home
4. Grip strength will be assessed in a willing sub-group of women (as muscle strength may change depending on vitamin D status) using a grip strength dynanometer. The average of three readings will be taken.
5. Incidence of chronic pain will be assessed using a pain mannikin questionnaire
Overall study start date01/10/2008
Completion date31/01/2010

Eligibility

Participant type(s)Patient
Age groupSenior
SexFemale
Target number of participants300 (100 participants for each intervention arm: high vitamin D, low vitamin D, and placebo)
Key inclusion criteriaWomen from a previous screening study (Aberdeen Prospective Osteoporosis Screening Study - APOSS) aged between 60 and 70 years.
Key exclusion criteriaPatricipants will be excluded if they:
1. Have been diagnosed with CVD
2. Have been diagnosed with diabetes
3. Have been diagnosed with asthma
4. Have high blood pressure (i.e. systolic blood pressure greater than 160 mmHg or diastolic pressure greater than 99 mmHg)
5. Suffer from chronic gastro-intestinal disease associated with malabsorption (e.g. coeliac disease, crohn's disease)
6. Are taking any medication regularly which might affect outcome measures such as hypotensive, hypolipemic, anti-inflammatory, or oral corticosteroid users
Date of first enrolment01/10/2008
Date of final enrolment31/01/2010

Locations

Countries of recruitment

  • Scotland
  • United Kingdom

Study participating centre

Osteoporosis Research Unit
Aberdeen
AB25 2ZD
United Kingdom

Sponsor information

University of Aberdeen (UK)
University/education

Research and Innovation
University Office
King's College
Aberdeen
AB24 3FX
Scotland
United Kingdom

Phone +44 (0)1224 272123
Email res-innov@abdn.ac.uk
Website http://www.abdn.ac.uk/R&I
ROR logo "ROR" https://ror.org/016476m91

Funders

Funder type

Government

Food Standards Agency (UK) (ref: N05R0015)
Private sector organisation / Other non-profit organizations
Alternative name(s)
The Food Standards Agency, FSA
Location
United Kingdom

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 01/10/2012 Yes No
Results article results 01/10/2013 Yes No
Results article results 01/01/2014 Yes No