Vitamin D May Improve Quality of Life in Fibromyalgia

In an analysis designed to evaluate the psychological outcomes of vitamin D supplementation in patients with fibromyalgia, the vitamin may be a complementary option for improving of psychological symptoms and quality of life, according to data published in Journal of Clinical Medicine.¹

Previous studies have demonstrated vitamin D improved emotional anxiety symptoms in patients with major depressive disorder, mitigated inflammation, and provided relief of post-herpetic neuralgia via antiviral efficacy enhancement. A vitamin D deficiency has also been linked to the severity of inflammatory bowel disease (IBD).²

“The efficacy of current pharmaceutical treatments for fibromyalgia are limited. Vitamin D has shown promise in relieving pain,” wrote a group of Taiwanese investigators led by Chia-Chun Yang, of the
Department of General Psychiatry at the Taoyuan Psychiatric Center. “This study aimed to investigate the impact of vitamin D supplementation on psychological outcomes and quality of life in fibromyalgia patients, given the unmet clinical need for effective treatment options.”

The meta-analysis sought to compare vitamin D to placebo in randomized controlled trials as well as to examine prospective studies analyzing changes before and after vitamin D supplementation in patients with fibromyalgia to determine the effects of the vitamin on psychological outcomes, quality of life, and pain scores in this patient population.

Databases, including PubMed, Web of Science, EMBASE, and the Cochrane Library, were searched through October 31, 2022. Eligible studies were published in English or Chinese, enrolled patients with fibromyalgia who received vitamin D supplementation, and reported on quality of life and psychological outcomes. Outcomes were measured by the Fibromyalgia Impact Questionnaire (FIQ), Visual Analog Scale (VAS), Beck Depression Inventory (BDI), the 36-item Short Form Health Survey (SF-36), Pittsburgh Sleep Quality Index (PSQI), and Widespread Pain Index (WPI).

Investigators ultimately included 8 trials, comprised of 694 participants, conducted in America, Turkey, Mexico, Iran, Austria, and Norway. Most studies administered a 50,000 IU weekly dose of vitamin D.

In 2 studies, vitamin D supplementation improved each of the 8 domains of SF-36 after 12-weeks and 1 demonstrated that 4 of 8 domains were significantly improved, with an emphasis on physical function (standard mean differences [SMD] = 0.44, 95% confidence interval [CI] = 0.10, 0.77), role limitations due to emotional health (SMD = 0.57, 95% CI = 0.32, 0.82), general health (SMD = 0.36, 95% CI = 0.11, 0.61), and social function (SMD = 0.50, 95% CI = 0.08, 0.93).

However, no notable improvements were observed in role limitations due to bodily pain (SMD = 0.92, 95% CI = 0.26, 1.57), mental health (SMD = 0.49, 95% CI = −0.09, 1.06), physical health problems (SMD = 0.61, 95% CI = 0.13, 1.09), and vitality (SMD = 0.61, 95% CI = −0.32, 1.53).

The FIQ scores demonstrated improvements (SMD = −0.414, 95% CI = [−0.808, −0.021]). However, similar improvements were not reported on the VAS (SMD = −0.15, 95% CI = −0.771, 0.471) and BDI scores (SMD = −0.456, 95% CI = −1.27, 0.30).

Investigators noted that the small sample size and the differences between diagnostic criteria hindered the analysis. Further, other confounding factors may have influenced the findings.

“Our study demonstrates that vitamin D is a safe, well-tolerable, and alternative intervention for improving psychological outcomes and quality of life in patients with fibromyalgia,” investigators concluded. “However, to confirm the clinical implications of these findings, future trials with larger sample sizes, controlling for potential confounding factors, and with long-term follow-up are warranted.”

References

1. ^{Yang CC, Tsai ST, Ting B, et al. Psychological Outcomes and Quality of Life of Fibromyalgia Patients with Vitamin D Supplementation-A Meta-Analysis. J Clin Med. 2023;12(7):2750. Published 2023 Apr 6. doi:10.3390/jcm12072750}
2. ^{Karkeni, E.; Bonnet, L.; Marcotorchino, J.; Tourniaire, F.; Astier, J.; Ye, J.; Landrier, J.-F. Vitamin D limits inflammation-linked microRNA expression in adipocytes in vitro and in vivo: A new mechanism for the regulation of inflammation by vitamin D. Epigenetics 2018, 13, 156–162.}