Hypovitaminosis D Prediction Score

Study Overview
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Brief Summary
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Vitamin D has effects on many tissues, and hypovitaminosis D is frequent. In a French survey conducted among 1587 adults, vitamin D insufficiency (<30ng/ml) has been reported in 80% of subjects, including 43% with moderate deficiency (<20ng/ml) and 5% with severe deficiency (<10ng/ml). Because of the possible consequences of hypovitaminosis D (osteomalacia in adults…), the number of vitamin D determination has increased ten-fold since 2005 in France, reaching 4.5 million € in 2011, and with it the costs for health insurance. However, there is currently no consensus on the strategy for detection, diagnosis and treatment of hypovitaminosis D. We propose to develop a predictive clinical score of hypovitaminosis D based on the accurate assessment of solar exposure, vitamin D intakes and hypovitaminosis D risk factors collected through a self-administered questionnaire.

Official Title
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SCOPYD Study: Development of a Predictive Clinical Score of Hypovitaminosis D

Conditions
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Vitamin D Status

Intervention / Treatment
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* Biological: Blood sampling
* Other: self-administered questionnaire


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Men and women aged 18 to 70 years old Exclusion Criteria: Participation in a study related to vitamin D Taking at least 80 000 IU vitamin D in the last 3 months as a single dose Pregnancy or breast-feeding Renal failure : severe renal impairment, dialysis, having kidney transplant Known hepatic impairment Gastrointestinal disorders: Celiac disease, Crohn's disease, ulcerative colitis, bariatric surgery, gastrointestinal surgery with stoma Known primary hypo/hyperparathyroidism Bone cancer/metastases current or in the last 2 years Treatment with antiepileptics Long-term treatment with glucocorticoids (> 3 months) Treatment with antiretroviral Legal incapacity or limited legal capacity Non-recipient of French Social Security

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vitamin D status<br>The 2500 subjects included in this unique arm will complete a self-administered questionnaire and will have a blood sampling to measure vitamin D blood concentration. | Biological: Blood sampling<br>* Patients will have a blood sampling at inclusion to measure vitamin D blood concentration.<br>Other: self-administered questionnaire<br>* Patients will fill a self-administered questionnaire the day of inclusion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 25 (OH) vitamin D blood concentration | Vitamin D determination will be carried out for each center in a single laboratory by chemiluminescence technique. Vitamin D determination is the gold standard for the development and validation phases of the score. It will define the variables of the self-administered questionnaire to be included in the final score (development phase) and be the gold standard in the evaluation of the performance score (validation phase). The blood sample will be collected after the completion of the questionnaire, on the same day. | The day of inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vitamin D concentration level | The ability of the score to classify adults in one of these three categories: Category 1 : Vitamin D sufficiency (≥30 ng/ml) Category 2 : Hypovitaminosis D between 30 and 10 ng/ml Vitamin D insufficiency (<30 ng/ml) Vitamin D deficiency (<20 ng/ml) Category 3 : Severe deficiency (<10 ng/ml) | The day of inclusion |