Influence of Vitamin D Treatment on Multi-systemic Functions in Young Men With Vitamin D Deficiency Due to Work Conditions

Phase 4

Completed

• Conditions: Vitamin D Deficiency
• Interventions: Dietary Supplement: Vitamin D; Dietary Supplement: Placebo

• Registration Number: NCT01016184
• Lead Sponsor: Rambam Health Care Campus

Brief Summary

Vitamin D has multiple systemic effects: bone and calcium metabolism, muscle function, insulin responsiveness, body-composition regulation, cell differentiation, and the immune system. Proper status of vitamin D is found to be related to risk reduction in hypertension, cardiac and vascular diseases, autoimmune diseases, and others. Furthermore, vitamin D supplementation resulted in improved endothelial function. Limited sun exposure may lead to vitamin D deficiency, and it may be assumed that modern life styles lead to a lack of sun exposure. Long work-days may be the primary risk factor for vitamin D deficiency. The purpose of this research is to study the effect of vitamin D treatment on multi systemic functions in young healthy men with vitamin D deficiency due to working conditions.

Detailed Description

The study has 2 stages: first stage would be survey of 400 employees, who will fill out a questionnaire to identify occupational and demographic risk factors, a nutritional questionnaire, and data from periodic checkups will be collected. Participants will sign a consent form for vitamin D level determinations, and for freezing blood samples. From this survey, the participants that have vitamin D deficiency (25(OH)D levels \< 20 ng/ml) will continue to the second stage of the study - administration of vitamin D or placebo. Participants in the interventional study will sign an additional consent form. Length of follow-up: one year. All parameters will be tested at 0, 6, and 12 months.

Study Timeline

• Study Start: 2009-09
• Study First Submitted: 2009-11-18
• Study First Submitted QC: 2009-11-18
• Study First Posted: 2009-11-19
• Primary Completion: 2012-03
• Study Completion: 2012-03
• Status Verified: 2013-01
• Last Update Submitted: 2013-01-30
• Last Update Posted: 2013-02-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 358

Inclusion Criteria

• Healthy men between 20-65 years old
• For stage 2: baseline 25(OH)D levels < 20 ng/ml

Exclusion Criteria

• Liver dysfunction
• Kidney dysfunction
• Patients with unbalanced chronic diseases
• Regular use of medications that lower serum vitamin D levels, or which interfere with intestinal vitamin D absorption

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
vitamin D	Vitamin D	-
placebo	Placebo	-

Primary Outcome Measures

Name	Time	Method
Serum level of 25(OH)D	12 months

Secondary Outcome Measures

Name	Time	Method
Blood pressure, Endothelial function, Muscle strength. Quality of life, absence from work Laboratory measures:PTH, P1NP, β-CTx, Inflammation markers (hs-CRP), Fasting glucose levels, Insulin, Lipids profile	12 months

Trial Locations

Locations (1)

Rambam health care campus; 🇮🇱 Haifa, Israel