The Role of Vitamin D Supplementation on Well Being and Symptoms of Depression During the Winter Season in Health Service Staff

Study Overview
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Brief Summary
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The purpose of this study is to investigate whether vitamin D3 (70 micrograms) is better than placebo in preventing depression symptoms among employees in health care

Detailed Description
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Vitamin D3 is produced in the skin after exposure to ultraviolet B light from the sun. Vitamin D3 is metabolised sequential in the liver into 25-hydroxy-vitamin D [25(OH)D], which is the storage form of vitamin D in the body, and then in the kidney into the steroid hormone, 1a,25-dihydroxyvitamin 1a,25-dihydroxyvitamin D [1,25(OH)2D]. At higher latitudes ultraviolet B light is stopped by the atmosphere during winter season. Half of Danes have low levels of [25(OH)D] in the blood and especially in the early spring months the levels of [25(OH)D] are low. In addition, Vitamin D3 is absorbed through the gut from vitamin D-rich food sources. But several studies show that it is not possible through a recommended diet, which consists of 300 g of fish per week to consume adequate amounts of vitamin D3. New research suggests link between vitamin D3 and brain function.In the Central Nervous System (CNS) there are specific nuclear receptors for 1,25(OH)2D (VDR) and the enzymes necessary for the hydroxylation of 25(OH)D to 1,25(OH)2D are also present in CNS. In clinical studies, low serum levels of 25(OH)D, have been associated with reduced cognitive function, anxiety and depression. The objective of this randomized clinical trial is to investigate whether indoor employees, with tendency to depressive symptoms in the winter season, should be offered vitamin D3 supplements during the Winter season, or it has no significance in relation prevent depressive symptoms. The study is carried out in the winter season in the Region of Southern Denmark for 12 weeks and offered to health service staff, who have a tendency for depressive symptoms in the winter season.

Conditions
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Seasonal Affective Disorder, Vitamin D3, Mental Health, Dietary Supplement

Intervention / Treatment
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* Dietary Supplement: Vitamin D3
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Health service staff and employee in the Region of Southern Denmark. Tendency to depressive symptoms in the winter season SPAQ>7. Exclusion Criteria: clinical diagnosis sarcoidoses tuberculosis bipolar affective disorder schizophrenia hypercalcemia hyperphosphatemia pregnancy hyperparathyroidism reduced kidney function

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vitamin D3<br>one tablet of vitamin D3 (70µg) per day for 12 weeks. | Dietary Supplement: Vitamin D3<br>* 70µg Vitamin D3, daily, 12 weeks<br>* Other names: Active;|
| Placebo Comparator: placebo<br>one tablet of sugar pill per day for 12 weeks. | Drug: Placebo<br>* Placebo, daily, 12 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hamilton-29 | Change from baseline in Hamilton-29 at week 12 | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| WHO-5 | Change from baseline in WHO-5 at week 12 | 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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SPAQ, Sigh-SAD, Hamilton 29, Vitamin D3, p25(OH)D