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Fibromyalgia helped by Vitamin D – still not sure how much, and why - June 2016

Vitamin D in Fibromyalgia: A Causative or Confounding Biological Interplay?

Nutrients 2016, 8(6), 343; doi:10.3390/nu8060343
Spyridon Karras * , Eleni Rapti, Stauros Matsoukas and Kalliopi Kotsa
First Department of Internal Medicine, Division of Endocrinology and Metabolism, AHEPA Hospital, Thessaloniki 54636, Greece
FM suplementation with Vitamin D
Image

Fibromyalgia (FM) is a chronic syndrome with an increasing prevalence, characterized by widespread musculoskeletal pain in combination with a variety of cognitive symptoms and fatigue. A plethora of scientific evidence that has accumulated during the last decades, resulted in a significant improvement of the understanding of the pathophysiology of the disease. However, current therapeutic approaches in patients with FM remains a multidimensional approach including patient education, behavioral therapy, exercise, pain management, and relief of chronic symptoms, rather than the use drug therapies, based on the mechanisms of disease development. Vitamin D, a fat-soluble vitamin derived mainly from skin synthesis through ultraviolet radiation, has been recognized to manifest a plethora of extraskeletal actions, apart from its fundamental role in skeletal and calcium homeostasis, including modulation of cell growth, neuromuscular actions, and potential anti-inflammatory properties. Recent findings indicate that hypovitaminosis D to be highly prevalent in patients with FM. Supplementation studies are limited so far, indicating potential beneficial effects on pain and severity of the disease, however specific recommendations are lacking. This review aims to summarize and critically appraise data regarding the pathophysiological interplay between vitamin D and FM, available results from observational and supplementation studies so far, with a clinical discourse on current knowledge gaps and future r

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Current criteria
Pain and symptoms over the past week, based on the total number of: painful areas out of 19 parts of the body
PLUS level of severity of these symptoms:

  • a. Fatigue;
  • b. Waking unrefreshed;
  • c. Cognitive (memory or thought) problems

PLUS number of other general physical symptoms.

  • Symptoms lasting at least three months at a similar level.
  • No other health problem that would explain the pain and other symptoms

  • Fibromyalgia is the second most common disorder observed by rheumatologists, after osteoarthritis)) [1-3].
    Women are more likely to develop FM, since 85%-90% of the affected populations are females


Figure 1. Hypothetical pathophysiological mechanisms of vitamin D and FM interplay.
The presence of VDR receptors and the enzymatic action of 1-ahydroxylase in different areas of CNS and particularly in the hypothalamus, is implicated in the pathophysiology of FM and CWP
Vitamin D plays important role in neuronal regulation and modulates neurotransmitters and receptors like y-aminobutyric acid (GABA) and N-methyl-D-aspartate which correlates with FM
Vitamin D is involved in the production of Neural Growth Factor (NGF) which is implicated in the pathophysiology of FM
Neurotransmitters (acetylcholine, dopamine, serotonin) are associated with dysregulation of pain processing in FM
Inflammatory pathways associated with chronic pain like TGF-beta-1, interleukin-4 and nitric oxide (NO) are upregulated by vitamin D
Hypovitaminosis D results in myopathy of type II muscle fibers and fatty infiltration
Deep muscle hypersensitivity and balance deficit are associated with Vitamin D deficiency
Abbreviations: VDR: Vitamin D receptor; FM: Fibromyalgia; CNS: Central nervous system; CWP: Chronic widespread pain.

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