Findings from a recent meta-analysis published in the journal Pain Physician revealed a positive, although, crude association between hypovitaminosis D and chronic widespread pain, with the association likely to remain after adjustment of potential confounding factors.
Chronic widespread pain (CWP), which includes fibromyalgia, is a highly prevalent condition with a range of disabling symptoms, both physical and psychological. The musculoskeletal disorder leads to disability and a reduced quality of life and has a prevalence of 10% to 18% in the general population. Vitamin D is essential for maintaining homeostasis of the musculoskeletal system and low levels of this compound have long been proposed to be associated with CWP.
The most severe type of hypovitaminosis D, osteomalacia, features generalized body pain, especially in the shoulder, rib cage, and lumbar and pelvic regions. The biological relationship between CWP and vitamin D deficiency is still under investigation but studies suggest it may be mediated through vitamin D receptors on muscle tissues and vitamin D’s regulatory role in autoimmune responses.
To determine whether hypovitaminosis D was independently associated with CWP, in the study entitled “Is Serum Hypovitaminosis D Associated with Chronic Widespread Pain Including Fibromyalgia? A Meta-analysis of Observational Studies”, Tyng-Guey Wang, MD, from the Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital in Taiwan and colleagues, conducted an extensive database search from studies that investigated the prevalence of hypovitaminosis D and serum vitamin D levels between participants with and without CWP. A total of 12 studies were included in the analysis, comprising a total of 1,854 CWP patients.
The results showed that the group of subjects suffering from CWP showed a significantly higher risk of hypovitaminosis D when compared to the control group. The team observed there was a positive crude association between hypovitaminosis D and CWP. Importantly, using a cut-off value for hypovitaminosis D (8 – 10 ng/mL) allowed for a better definition of the population with and without CWP.
Based on these findings, the team highlights the need for future prospective follow-up studies in order to clarify the causal relationship between CWP and hypovitaminosis D.