Treat the cause with vitamin D intervention
Sometimes a diagnosis can be dangerous. This is especially true when it’s wrong.
Between 0.2 and 4.7% of the population have been diagnosed with fibromyalgia.1 A conclusion reached by the process of exclusion as there are no imaging techniques, lab studies or specific physical examination findings that definitively identify this condition. How can we be so sure?
The exact cause of fibromyalgia is not understood but is theorized to involve abnormal sensory processing leading to widespread pain and fatigue. The diagnosis is usually based on chronic pain and tenderness in at least 11 of 18 specific points accompanied by various other symptoms, including fatigue, sleep disturbance, headache, depression and/or anxiety.2
There is no cure, but treatment can help manage symptoms. Medications, or combinations of medications, may include pain relievers, muscle relaxants, antidepressants, antiseizures or sleep aids. Additionally, lifestyle changes may include regular exercise, stress reduction techniques, cognitive behavioral therapy and sleep hygiene.3 The prognosis is variable, but fibromyalgia is considered a chronic condition requiring ongoing management.
The symptoms of fibromyalgia may include some or all of the following:4
- Widespread musculoskeletal pain that lasts for more than three months
- Tenderness in localized areas known as trigger points
- Sleep disturbances
- Morning stiffness
- Restless legs syndrome
- Cognitive difficulties, including memory problems and difficulty concentrating
- Mood disorders, such as depression and anxiety
The above list is certainly nonspecific. Anyone could speculate widespread pain would cause sleep disturbances which, in turn, would lead to fatigue, memory impairment and/or depression. Alternatively, depression can yield fatigue, sleep disturbance and increased pain sensitivity. Or, this is an entirely incorrect pursuit.
Vitamin D insufficiency and deficiency is prevalent worldwide and defined in Table A.
Table A: Current laboratory levels for vitamin D
|25-hydroxycholecalciferol||US laboratory level||International laboratory level|
|Normal||>30 ng/ml||>75 nmol/L|
|Insufficiency||20-30 ng/ml||50-75 nmol/L|
|Deficiency||<20 ng/ml||<50 nmol/L|
Rates of deficiency are estimated to be >50% of many populations.5 There are several causes of vitamin D deficiency, including: avoidance of sunshine, frequent use of sunscreen, living at higher latitudes, having dark skin, aging, a history of bariatric surgery and use of several medications.
A number of drugs are known to interfere with vitamin D metabolism.6 Table B is arranged with the greatest to least negative.
Table B: Drugs associated with vitamin D insufficiency and deficiency
|Drug class||Generic name||Brand name|
|Antiandrogen||Cyproterone acetate||Cyprostat, Androcur|
Two natural compounds, kava kava and St. John’s wort, can similarly decrease vitamin D levels.6
Vitamin D deficiency in adults causes osteomalacia. Osteoporosis may be confused with osteomalacia. The normal human skeleton is composed of mineral components, including calcium hydroxyapatite (60%) and organic material, mainly collagen protein (40%).7
In osteoporosis, bones are porous and brittle, whereas in osteomalacia, bones are soft. This difference in bone consistency is related to the mineral-to-organic material ratio. In osteoporosis, the mineral-to-collagen ratio remains in the normal reference range. With osteomalacia, the proportion of mineral composition is reduced relative to organic matrix.7 As the bones soften, they tend to ache and are more prone to fracture.
The following are symptoms of osteomalacia:
- Vague muscle and bone aches
- Increased susceptibility to fracture
- Muscle weakness
Due to the vague and nonspecific symptom picture, vitamin D deficiency frequently escapes recognition, especially in the early presentation.8
Unlike fibromyalgia, there are objective signs of osteomalacia, including:
- Low serum 25-hydroxycholecalciferol
- Elevated alkaline phosphatase
- Decreased bone mineral density on a DXA examination
The most accurate test for osteomalacia is a bone biopsy, a painful procedure. If osteomalacia is suspected, it’s best to pursue a comprehensive metabolic panel, blood level of vitamin D and a DXA (bone density test). If the results are consistent with osteomalacia, you should begin vitamin D treatment.
In regard to 25-hydroxycholecalciferol levels, anyone with a result of <20 ng/ml (the definition of deficiency) will have impaired mineralization. This is osteomalacia. Given vitamin D levels fluctuate between winter and summer months, noting the time of year for testing is important.
For example, if a test result is 31ng/ml at the end of summer, the levels will likely bottom out at approximately 18 ng/ml at the end of winter. This patient would be deficient for a portion of the year and insufficient most months in spite of a test result in the normal range.
With known deficiency, the combined vitamin D sources of sunshine, food and supplements should add up to at least 5,000 IUs (125 mcg) per day. Because vitamin D is fat-soluble, obese patients will require two to three times the suggested 5,000 IUs.9 Other protocols call for 50,000 IU/week for 12 weeks.10 All interventions should include a retest. The quantities necessary to overcome deficiency will vary with individuals; however, the more important consideration is blood levels.
- The symptoms of osteomalacia and fibromyalgia have significant overlap.
- As there are no identifying lab or imaging tests, fibromyalgia is a diagnosis of exclusion.
- Osteomalacia can be suspected in a symptomatic patient with low serum 25-hydroxycholecalciferol, low serum calcium and/or high alkaline phosphatase.
- Osteomalacia can be directly attributed to vitamin D deficiency.
The common default diagnosis of fibromyalgia may be an overlooked vitamin D deficiency leading to osteomalacia. This is a source of widespread pain which, in turn, causes sleep disturbances and mood changes. Intervention with large doses of vitamin D to objectively increase blood levels is treating the cause.
The steps below should be followed if osteomalacia is suspected:
- Refer for laboratory studies (comprehensive metabolic panel and 25-hydroxycholecalciferol).
- Refer for DXA.
- If results are consistent with osteomalacia, begin vitamin D treatment.
- Retest vitamin D in 12-16 weeks.
ALAN COOK, DC, has been in practice since 1989. To see more of his work, go to Easywebce.com, which provides chiropractic continuing education in a web-based video format. He can be reached at Easywebce@gmail.com.
- Marques AP, et al. Prevalence of fibromyalgia: Literature review update. Revista Brasileira de Reumatologia. 2017;57:356-363. PubMed website. https://pubmed.ncbi.nlm.nih.gov/28743363/. Accessed Sept. 18, 2023.
- Rahman A, et al. Fibromyalgia. BMJ. 2014;348:1224. PubMed website. https://pubmed.ncbi.nlm.nih.gov/24566297/. Accessed Sept. 18, 2023.
- Goldenberg DL, et al. Management of Fibromyalgia Syndrome. JAMA. 2004;292(19):2388-2395. PubMed website. https://pubmed.ncbi.nlm.nih.gov/15547167/. Accessed Sept. 18, 2023.
- Wolfe, F. Fibromyalgia: Whither treatment? J. Rheumatol.1988;15:1047–1049. Europe PMC website. https://europepmc.org/article/MED/3172111.Accessed Sept. 18, 2023.
- Roth DE, et al. Global prevalence and disease burden of vitamin D deficiency: A roadmap for action in low- and middle-income countries. Acad. Sci. 2018;1430: 44-79. NYAS website. https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/nyas.13968. Accessed Sept. 18, 2023.
- Gröber U, Kisters K. Influence of drugs on vitamin D and calcium metabolism. Dermatoendocrinol. 2012;4(2):158-66. Taylor and Francis website. https://www.tandfonline.com/action/showCitFormats?doi=10.4161%2Fderm.20731. Accessed Sept. 18, 2023.
- Russell LA. Osteoporosis and osteomalacia. Rheumatic disease clinics. 2010;36:665-680. The clinics.com website. https://www.rheumatic.theclinics.com/article/S0889-857X(10)00078-5/fulltext. Accessed Sept. 19, 2023.
- Bhan A, et al. Bone histomorphometry in the evaluation of osteomalacia. Bone Reports. 2018;8:125-134. PubMed website. https://pubmed.ncbi.nlm.nih.gov/29955631/. Accessed Sept. 18, 2023.
- Holick MF. Resurrection of vitamin D deficiency and rickets. J Clin Invest. 2006;116(8):2062-2072. PubMed website. https://pubmed.ncbi.nlm.nih.gov/. Accessed Sept. 18, 2023.
- Khan QJ, et al. Effect of vitamin D supplementation on serum 25-hydroxy vitamin D levels, joint pain, and fatigue in women starting adjuvant letrozole treatment for breast cancer. Breast Cancer Res Treat. 2010;119:111–8. PubMed website. https://pubmed.ncbi.nlm.nih.gov/19655244/. Accessed Sept. 18, 2023.