Vitamin D status, CVD risk, insulin sensitivity Nutritional, Metabolic, Endocrine Vitamin supplementation
Conditions
Interventions
This 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 f
Sponsors
University of Aberdeen (UK)
Eligibility
Sex/Gender
Female
Inclusion criteria
Inclusion criteria: Women from a previous screening study (Aberdeen Prospective Osteoporosis Screening Study - APOSS) aged between 60 and 70 years.
Exclusion criteria
Exclusion criteria: Patricipants 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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| All 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
| Measure | Time frame |
|---|---|
| All 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 | — |
Countries
United Kingdom
Outcome results
None listed