Plain English Summary
Background and study aims.
Many non-Western immigrants suffer non-specific pain in arms, legs or backbone. These complaints are often diagnosed as fibromyalgia or depression and sometimes a lot of effort is put into finding specific causes. Many press and scientific reports suggest that these complaints may be caused by a lack of vitamin D, and recommend taking extra vitamin D (supplementation) as a cheap and harmless way to handle this hard-to-treat condition. This study tried to find out if this would be successful.
Who can participate?
Non-Western immigrants aged between 18 and 65 years who sought help for non-specific pains lasting longer than 3 months at their general practitioner and had low levels of vitamin D were asked to participate in this study.
What does the study involve?
Participants were randomly allocated to a dummy treatment (known as a placebo) or vitamin D (150,000 IU vitamin D3 orally); after 6 weeks, patients in the original vitamin D group were randomly allocated a second time to receive either vitamin D (again) or to switch to placebo, whereas patients in the original placebo group were all switched to vitamin D. At start and at 6 and 12 weeks after, they were interviewed by trained interpreters about their pain and ability to walk stairs. Neither participants nor interpreters were aware if the patient had received placebo or vitamin D.
What are the possible benefits and risks of participating?
Neither the participants nor their general practitioners had any financial benefit for participating. The used dose vitamin D3 was widely thought to be totally safe, so the main risk for (half of) the participants was being supplemented 6 weeks later than possible.
Where is the study run from?
8 practices in Delft, The Netherlands
When is the study starting and how long is it expected to run for?
The study started in 2007 and ended in 2011.
Who is funding the study?
This study was an investigator-driven study without any funding.
Who is the main contact?
Dr Ferdinand Schreuder
Dr F. Schreuder
+31 (0)15 262 2624
Vitamin D supplementation can relieve aspecific musculoskeletal disorders in allochtone patients.
Received from the local ethics committee (METC-zwh).
Randomised, double blinded, placebo controlled, crossover group, multicentre trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Aspecific musculoskeletal disorders, vitamin D supplementation
Due to difficulties obtaining study medication, the trial has been posponed. The trial was due to start on the 1st September 2007, and was posponed intially to 1st October 2007, but now is anticipated to start on the 1st September 2008.
Since the above mentioned changes to the start date, and as of 28th January 2008 the anticipated start date of this trial has now been finalised and is planning to start on the 4th February 2008.
150,000 IU vitamin D3 or placebo in one oral dose at week 0. Patients cross over to other treatment at week six (but: if given placebo at week 0, one will always get vitamin D3).
Primary outcome measure
Differences in improvement of pain as assessed by questionnaires at week 0 and 6 (between placebo and vitamin D3 groups).
Secondary outcome measures
1. Differences in improvement of pain as assessed by questionnaires at week 12 (between 150,000 and 300,000 vitamin D3-group)
2. Serum 25-OH-D levels at week 12 (150,000 and 300,000 group)
3. Differences in improvement of pain as assessed by questionnaires at week 6 and week 12 (between placebo - vitamin D3 group and vitamin D3 - placebo group)
4. Serum 25-OH-D levels at week 12 (placebo - vitamin D3 group and vitamin D3 - placebo group)
5. Correlations between localisation of complaints, improvement of pain as assessed by questionnaires, initial serum 25-OH-D levels and serum 25-OH-D levels at week 12
6. Differences in ability to walk stairs as assessed by questionnairies at week 6 and 12 between placebo and vitamin D group
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Asian and African men and women, visiting their general practitioner
2. Aged 18 to 60 years
3. Greater than thirteen weeks aspecific musculoskeletal disorders (i.e., musculoskeletal complaints without a specific cause like:
3.1. Trauma or infection, or
3.2. Localisation (like gonarthrosis), or
3.3. Complex of symptoms (like Herniated Nucleus Pulposus [HNP], Polymyalgia rheumatica).
Included are for instance low-back pain, fibromyalgia, fasciitis plantaris. Depression is NOT an exclusion criterion
4. Serum 25-hydroxyvitamin D (25-OH-D) level less than 50 nmol/ml
Target number of participants
Participant exclusion criteria
2. Vitamin D supplementation in the last four months
4. Renal insufficiency
6. Tuberculosis (TBC)
7. Peanut allergy
8. Use of cyclosporins, statins or oral steroids
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Individual sponsor (Netherlands)
c/o Dr F. Schreuder
Individual funder - Dr F. Schreuder (The Netherlands)
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
1. 2012 results in http://www.ncbi.nlm.nih.gov/pubmed/23149532
Schreuder F, Bernsen RM, van der Wouden JC, Vitamin D supplementation for nonspecific musculoskeletal pain in non-Western immigrants: a randomized controlled trial., Ann Fam Med, 10, 6, 547-555, doi: 10.1370/afm.1402.