The Role of Narrowband Ultraviolet B Exposure in the Maintenance of Vitamin D Levels During Winter

Study Overview
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Brief Summary
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The investigators investigated the ability of narrowband ultraviolet B (nbUVB) treatment in the maintenance of vitamin D levels achieved during the summer in Finland. The investigators randomized 37 subjects into groups of 17 and 18 subjects. The other group received 2 standard erythema doses (SED) nbUVB exposure every other week until week 24, and serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30. The control group was not illuminated and serum samples were analyzed correspondingly. Punch biopsies were taken at the onset and at week 14 for CYP27A1 and CYP27B1 enzyme expression level analyses.

Detailed Description
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The investigators investigated the ability of narrowband ultraviolet B (nbUVB) treatment in the maintenance of vitamin D levels achieved during the summer in Finland. The investigators randomized 37 subjects into groups of 17 and 18 subjects. The other group received 2 standard erythema doses (SED) nbUVB exposure every other week until week 24, and serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30. The control group was not illuminated and serum samples were analyzed correspondingly. 6mm punch biopsies were taken at the onset and at week 14 for CYP27A1 and CYP27B1 enzyme expression level analyses.

Official Title
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The Role of Narrowband Ultraviolet B Exposure in the Maintenance of Vitamin D Levels During Winter

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Radiation: nbUVB


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age over 18 Fitzpacker's skin type II-IV Exclusion Criteria: age under 18 diseases that inhibit vitamin D metabolism or absorption Fitzpacker's skin type I history of skin cancer vitamin D substitution 1 month before baseline or during study sun holidays 1 month before baseline or during study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: nbUVB<br>2 SED dose of nbUVB will be given every other week for this intervention group. | Radiation: nbUVB<br>* 2 SED nbUVB exposure will be given every other week<br>|
| No Intervention: control<br>No nbUVB illumination will be given for the control group. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 25(OH)D level | Serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30. | up to 30 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CYP27A1 and CYP27B1 enzyme expression levels | CYP27A1 and CYP27B1 enzyme expression levels will be analysed from 6mm punch biopsies at the onset and at week 14. | up to 14 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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calcidiol, 25(oh)d, nbUVB, cyp27A1, cyp27B1, vitamin D