Serum vitamin D levels in patients with Fibromyalgia Syndrome

A team of researchers at Ben-Gurion University, Israel have carried out a study that found no link between Fibromyalgia Syndrome and low levels of vitamin D.

The results of the article were published in the June edition of the Israel Medical Association Journal. In the article, the researchers explain the background, saying that the association between low levels of 25-hydroxyvitamin D (25OHD or vitamin D) and non-specific musculoskeletal pain, including Fibromyalgia Syndrome, is controversial with several past studies reporting a "positive association" and two others finding "no association".

This latest study tested levels of 25OHD in patients with Fibromyalgia Syndrome and in matched controls. The study population comprised 68 premenopausal women with a diagnosis of Fibromyalgia Syndrome and 82 age-matched premenopausal women without. The former were identified from the computerized medical databases of five primary care urban clinics in the south of Israel, and the control subjects were attending the participating clinics for regular periodic blood tests.

For each patient, the interview and blood test with the matched control subject were performed within a week or two from the patient's interview and blood test, thus controlling for expected seasonal variations. Serum 25OHD was measured using different cutoff levels (< 30 ng/ml, < 20 ng/ml and <15 ng/ml) and compared between the groups.

The researchers found that no statistically significant differences were found between the groups regardless of the cutoff level used. A logistic regression model for predicting women with 25OHD levels 20 ng/ml showed that all the variables examined in both groups (age, country of birth, education) were not statistically significant. The researchers found the expected seasonal variations of 25OHD levels, but these were not statistically significant.

The researchers found that the prevalence of low vitamin D was particularly high in the study participants, whether or not they had Fibromyalgia Syndrome, with 48% having 25OHD levels < 20 ng/ml.

The conclusion of the team of researchers was that they found no association between Fibromyalgia Syndrome and low 25OHD levels as had been previously suggested in other studies. However, the researchers discussed the problems with carrying out studies of this kind, partly because of large variations in the prevalence of low vitamin D even in one population group.

To read the full article, click here.

References:

1. Tandeter H, Grynbaum M, Zuili I, Shany S, Shvartzman P. Serum 25-OH vitamin D levels in patients with fibromyalgia. Isr Med Assoc J. 2009 Jun;11(6):339-42.