Chronic Pain and Vitamin D

Study Overview
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Brief Summary
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Non-systematized chronic musculoskeletal pains are a frequent reason for consulting in general practice. The possible causes are numerous and sometimes nonspecific. In some cases, the etiologic investigation of patients with non-systematized and chronic musculoskeletal pain can not highlight any organic cause. Several studies have shown a link between these symptoms and vitamin D deficiency, characterized by a blood level of 25 (OH) vitamin D < 20.8ng/ml. This deficit is easy to identify and to correct through proper vitamin D supplementation with few side effects. Nevertheless, it remains unknown and vitamin D deficiency is rarely considered as a possible etiology in patients with chronic pain. We hypothesize that vitamin D supplementation in patients with non-systematized musculoskeletal pain and deficient in vitamin D could improve painful symptoms. We aim to perform a double-blind randomized controlled trial, vitamin D versus placebo, to assess the pain improvement after vitamin D supplementation.

Official Title
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Chronic Pain and Vitamin D: a Randomized Pilot Study in General Practice

Conditions
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Chronic Musculoskeletal Pain, Vitamin D Supplementation

Intervention / Treatment
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* Drug: vitamin D (cholecalciferol)
* Drug: Placebo, similar in appearance and taste to cholecalciferol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women and men Aged 18-50 years (included) Consulting their general practitioner With chronic and diffuse musculoskeletal pain, without known etiology, lasting for at least 3 months With a 25(OH)vitamin D deficiency <20.8 ng/ml (52 nmol/l) at inclusion Who signed the consent form Exclusion Criteria: Identifiable source of pain requiring an appropriate specific management Disease or treatment that may interfere with the metabolism of vitamin D Current or previous hypercalcemia or hypercalciuria, treatment with digitalics and patients with history of nephrolithiasis Current treatment with vitamin D or at least one vitamin D vial taken over the previous 6 months Pregnancy or breastfeeding not affiliated to a social security system Refusal or inability to give consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: vitamin D<br>Patients receiving 3 doses of vitamin D (cholecalciferol) | Drug: vitamin D (cholecalciferol)<br>* Patients from the vitamin D arm will receive an orally supplementation of 600 000 UI cholecalciferol in 3 doses: 200 000 UI at baseline (day 1), 200 000 UI on day 15 and 200 000 UI on day 30. Cholecalciferol will be presented in blisters, in a non-differentiable form in appearance and taste from placebo, either for the patient or the doctor<br>|
| Experimental: Placebo<br>Patients receiving 3 doses of placebo according to the same schedule as experimental arm | Drug: Placebo, similar in appearance and taste to cholecalciferol<br>* Patients from the placebo arm will receive 3 doses of placebo to be taken orally: one at baseline (day 1), one on day 15, one on day 30. Placebo will be presented in blisters in a non-differentiable form in appearance and taste from cholecalciferol either for the patient or the doctor.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of patients in the two groups who reported a decrease in the overall pain after 3 months of treatment with vitamin D versus placebo. | item 5 of the Brief Pain Inventory will be measured in each patient to assess the overall pain score at inclusion and after 3 month of treatment with vitamin D or placebo | 3 months after inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| : Proportion of patients in both groups reporting an evolution of the minimum and the maximum of intensity of pain | item 3 and 4 of the Brief Pain Inventory will be measured in each patient to assess the minimum and the maximum pain scores at inclusion, after 45 days and after 3 months of treatment with vitamin D or placebo | 3 months after inclusion | 
| Proportion of patients in both groups reporting a decrease in the impact of pain on daily activities | item 9 of the Brief Pain Inventory will be measured in each patient to assess the score of the impact of pain on daily activities at inclusion, after 45 days and after 3 months of treatment with vitamin D or placebo | 3 months after inclusion | 
| Proportion of patients reporting a decrease in the consumption of analgesic drugs | Patients of both groups will be asked at inclusion, after 45 days and after 3 months, if they took analgesic drugs: name, class and dose of each treatment will be registered in a standardized questionnaire | 3 months after inclusion | 
| Proportion of patients in both groups reporting a decrease in the consumption of care (consultations and work stoppages) | Patients of both groups will be asked at inclusion, after 45 days and after 3 months, if they consulted any health care professional : which health care professional, how many time, the reason for consultation and work stoppages will be registered in a standardized questionnaire | 3 months after inclusion | 
| Proportion of patients in both groups reporting an improvement in quality of life | Quality of life will be measured in patients of both groups by the SF-36 questionnaire, at inclusion and after 90 days. | 3 months after inclusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D deficiency, Musculoskeletal pain, Vitamin D supplementation