Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
5625
Study information
Scientific title
Sun exposure levels for provision of vitamin D sufficiency in people of skin type V living in the UK
Acronym
Study hypothesis
1. What is the effect on vitamin D status in people of skin type V, of the amount of UV exposure recommended for white Caucasian subjects, and how much extra UV exposure do skin type V people require?
Intervention study:
A UV course will be given to 60 subjects in January/February, using a whole body cabinet with lamps emitting a UV spectrum similar to sunlight. Blood 25(OH)D levels measured weekly.
2. What levels of vitamin D are attained through natural sunlight exposure in skin type V individuals living in the UK? How do these relate to personal UV exposure doses? Does the relationship differ from that in white Caucasian individuals?
Observation study:
125 subjects will have blood 25(OH)D levels assessed once in each season, UV exposure measured through polysulphone badges and dietary vitamin D assessed through diet diaries.
The results of the experimental work in the intervention study can be related to the findings of the real population in the observation study. Moreover, both studies in skin type V volunteers can be related to the findings of the equivalent studies in the white Caucasian subjects.
Ethics approval
North Manchester Research Ethics Committee approved on the 20th May 2008 (ref: 08/H1006/24)
Study design
Single centre non-randomised prevention and treatment trial
Primary study design
Observational
Secondary study design
Single-centre
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Topic: Skin; Subtopic: Skin (all Subtopics); Disease: Dermatology
Intervention
1. Intervention study:
1.1. Subjects were given simulated summer's sun exposures from a constant UVR dose via a full body cabinet, 3 times a week for 6 weeks. The subjects were split into 6 groups receiving either 0.65, 1.3 1.95, 2.6, 3.2, 3.9 SED. This was given in Jan/Feb, when there is no confounding ambient UVR
1.2. Vitamin D (25(OH)D) blood samples were taken pre-intervention and then weekly for 6 weeks
1.3. Patients completed diet diaries (1st week and 6th week) to assess dietary vitamin D
2. Observational study:
2.1. Vitamin D (25(OH)D) blood samples were taken in each season of the year (April - Spring, July - Summer, October - Autumn, January - Winter)
2.2. The subjects were also given polysulphone film badges to wear on their clothes for one week in each season to measure ambient UV
2.3. Sun exposure diaries were also used to give additional information about seasonal UV exposure
2.4. A diet diary was completed in each season for dietary vitamin D assessment.
Follow up was for one year.
The interventional follow up was for 7 weeks, the actual intervention (not treatment) was carried out over 6 weeks.
Intervention type
Supplement
Phase
Not Applicable
Drug names
Vitamin D
Primary outcome measures
1. Intervention study: % number of people reaching sufficient levels of vitamin D following simulated summer exposure
2. Observational study: the post summer vitamin D level required to maintain sufficiency throughout the winter months
Secondary outcome measures
Interventional study:
1. The % numbers reaching optimal levels of vitamin D following simulated summer sun exposure
2. Baseline winter levels of vitamin D deficiency, sufficiency and optimal levels
Overall trial start date
01/09/2008
Overall trial end date
30/05/2009
Reason abandoned
Eligibility
Participant inclusion criteria
1. Aged 18 - 65 years old
2. South Asian descent
3. Male or female
4. Sun-reactive skin type V
5. Ambulant
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
Planned sample size: 185
Participant exclusion criteria
1. History of skin cancer (intervention study)
2. History of a photosensitivity disorder (both)
3. Regular sunbathing/use of sunbeds (observational study)
4. Sunbathing/use of sunbeds in the past 3 months (intervention study)
5. Taking photoactive medication (interventional)
6. Pregnant or breast-feeding (interventional)
Recruitment start date
01/09/2008
Recruitment end date
30/05/2009
Locations
Countries of recruitment
United Kingdom
Trial participating centre
Photobiology Unit
Salford
M6 8HD
United Kingdom
Sponsor information
Organisation
University of Manchester (UK)
Sponsor details
c/o Mohammed Zubair
FMHS Research Office
3.53 Simon Building
University of Manchester
Manchester
M13 9PL
United Kingdom
Sponsor type
University/education
Website
Funders
Funder type
Charity
Funder name
Cancer Research UK (CRUK) (UK)
Alternative name(s)
Funding Body Type
private sector organisation
Funding Body Subtype
other non-profit
Location
United Kingdom
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary
1. 2011 results in http://www.ncbi.nlm.nih.gov/pubmed/21918215
2. 2013 results in http://www.ncbi.nlm.nih.gov/pubmed/23615828
Publication citations
-
Results
Farrar MD, Kift R, Felton SJ, Berry JL, Durkin MT, Allan D, Vail A, Webb AR, Rhodes LE, Recommended summer sunlight exposure amounts fail to produce sufficient vitamin D status in UK adults of South Asian origin., Am. J. Clin. Nutr., 2011, 94, 5, 1219-1224, doi: 10.3945/ajcn.111.019976.
-
Results
Farrar MD, Webb AR, Kift R, Durkin MT, Allan D, Herbert A, Berry JL, Rhodes LE, Efficacy of a dose range of simulated sunlight exposures in raising vitamin D status in South Asian adults: implications for targeted guidance on sun exposure., Am. J. Clin. Nutr., 2013, 97, 6, 1210-1216, doi: 10.3945/ajcn.112.052639.