Association between serum 25-hydroxyvitamin D levels and self-reported chronic pain in older adults: A cross-sectional analysis from the ViDA study

Serum Vitamin D and Chronic Musculoskeletal Pain: A Cross-Sectional Study of 349,221 Adults in the UK

Insufficient and deficient vitamin D may be associated with chronic musculoskeletal pain, but study findings are conflicting, and few account for important confounding factors. This cross-sectional study explored the association between serum vitamin D status and chronic musculoskeletal pain in various body sites, adjusting for a wide range and a number of potential confounding factors. Data collected at the baseline assessments of 349,221 UK Biobank participants between 2006 and 2010 were analyzed. Serum 25-hydroxyvitamin D was measured and categorized as <25.0 nmol/L (severe deficiency), 25.0 to 49.9 nmol/L (deficiency), 50.0 to 74.9 nmol/L (insufficiency), and ≥75.0 nmol/L (sufficiency). The outcome was self-reported chronic musculoskeletal pain at any site, neck/shoulder, back, hip, knee, or widespread pain that interfered with usual activities. Potential confounders were identified using directed acyclic graphs and included sociodemographic, lifestyle, psychological factors, and medical comorbidities. Simple models adjusted for age and sex showed significant associations between suboptimal vitamin D status and chronic pain across all sites (odds ratios [ORs] ranged 1.07-2.85). These associations were weakened or became insignificant after accounting for all confounding factors (ORs ≤ 1.01) for chronic regional musculoskeletal pain. Severe vitamin D deficiency remained a significant and positive association with chronic widespread pain after adjusting for all confounding factors (OR [95% confidence interval]: 1.26 [1.07, 1.49]). This study suggests that, while vitamin D status is not a key independent determinant of chronic regional musculoskeletal pain, severe vitamin D deficiency may be associated with chronic widespread pain. PERSPECTIVES: After accounting for various confounders, vitamin D deficiency was not associated with regional musculoskeletal pain. However, the relationship between chronic widespread pain severe vitamin D deficiency remained after confounder adjustment. Use of vitamin D supplements in individuals with chronic widespread pain and severe vitamin D deficiency warrants further exploration.

Causal effect of serum 25-hydroxyvitamin D levels on low back pain: A two-sample mendelian randomization study

Background: Previous observational studies have suggested the involvement of 25-hydroxyvitamin D [25(OH)D] in chronic pain. However, whether the 25(OH)D is a novel target for management, the causality remains unclear.

Methods: A two-sample Mendelian randomization (MR) study was conducted to identify the causal association between 25(OH)D and low back pain (LBP). The primary analysis was revealing causality from serum 25(OH)D level (n = 417,580) on LBP (21,140 cases and 227,388 controls). The replicated analysis was performing MR estimates from circulating 25(OH)D concentration (n = 79,366) on LBP experienced last month (118,471 cases and 343,386 controls). Inverse variance weighted (IVW) was used as the main analysis. In addition, we used weighted median and MR-Egger to enhance the robustness. Sensitivity analysis was conducted to evaluate the robustness of MR results.

Results: IVW estimation indicated strong evidence that higher serum 25(OH)D levels exerted a protective effect on LBP (OR = 0.89, 95% CI = 0.83–0.96, p = 0.002). Similar trends were also found in replicate analysis (OR = 0.98, 95% CI = 0.96–1.00, p = 0.07). After meta-analysis combining primary and replicated analysis, the causal effect is significant (p = 0.03). Sensitivity analysis supported that the MR estimates were robust.

Conclusion: In our MR study, genetically increased serum 25(OH)D levels were associated with a reduced risk of LBP in the European population. This might have an implication for clinicians that vitamin D supplements might be effective for patients with LBP in clinical practice.

Association Between Serum 25-Hydroxyvitamin D Concentrations, CDX2 Polymorphism in Promoter Region of Vitamin D Receptor Gene, and Chronic Pain in Rural Japanese Residents

Background

Previous studies examined the association between chronic pain (CP) and serum 25-hydroxyvitamin D (25(OH)D) concentrations; however, the findings obtained were inconsistent. Single nucleotide polymorphisms (SNP) associated with the transcriptional activity of the vitamin D receptor (VDR) gene may influence the association of 25(OH)D levels with CP. We aimed to clarify the association between CP, serum 25(OH)D concentration, and SNPs.

Methods

In the Shika study, we performed a cross-sectional analysis of 551 participants older than 40 years who were asked whether they had been having persistent pain lasting for at least 3 months in any part of the body on a self-administered questionnaire. Serum 25(OH)D concentrations were assessed as a biomarker of the vitamin D status using a radioimmunoassay. rs731236, rs7975232, rs1544410, rs2228570, and rs11568820 were identified using peripheral blood samples, and participants were assigned to those with or without the minor allele for each SNP.

Results

The prevalence of CP was 37.2%. We observed a tendency for lower 25(OH)D levels in participants with CP than in those without CP in the hetero/minor group of rs11568820, which is a polymorphism within the CDX2-binding site in the 1e promoter region of the VDR gene. Furthermore, a logistic regression analysis revealed that lower serum 25(OH)D concentrations were significantly associated with CP in the hetero/minor group, but not in the major group.

Conclusion

These results suggest that sufficient serum 25(OH)D concentration reduces the risk of CP in individuals with the minor allele of the CDX2 polymorphism.

The Role of Vitamin D in the Management of Chronic Pain in Fibromyalgia: A Narrative Review

INTRODUCTION

Fibromyalgia (FM) is a complex disorder characterized primarily by chronic, widespread musculoskeletal pain. Currently, the Food and Drug Administration (FDA) has approved the use of three medications to treat FM: pregabalin, duloxetine, and milnacipran. The pharmaceutical intervention has lacked consistent pain relief among all patients. Therefore, the investigation into alternative treatment options has grown in interest. This narrative review aims to evaluate the evidence regarding vitamin D for the treatment of FM.

METHODS

Narrative review.

RESULTS

Low serum vitamin D has been linked to various chronic pain states. An association between vitamin D deficiency and FM has been reported but is controversial in the literature. Some studies have documented the beneficial effects of vitamin D supplementation on reducing pain symptoms and improving the overall quality of life in those with FM. Despite these positive findings, many of the studies regarding this topic lack adequate power to make substantial conclusions about the effects of vitamin D on FM.

CONCLUSION

Existing studies provide promising results. However, additional high-quality data on vitamin D supplementation is needed before recommendations for pain management can be made. Vitamin D supplementation is inexpensive, has minimal side effects, and can benefit FM patients regardless of its efficacy in pain control. Additionally, high-quality studies are warranted to fully elucidate the potential of vitamin D to manage chronic pain in FM.

Association Between Serum 25-Hydroxyvitamin D Concentrations and Chronic Pain: Effects of Drinking Habits

Purpose

Although the explanation for inconsistencies in the reported association between serum 25-hydroxyvitamin D [25(OH)D] levels and chronic pain (CP) has not yet been determined, understanding this discrepancy is necessary for the development of vitamin D supplementation as an effective treatment for CP. The aim of this cross-sectional study was to examine the relationship between 25(OH)D concentrations and CP according to drinking habits in Japanese subjects.

Patients and Methods

We distributed invitation letters to 2314 individuals older than 40 years in Shika town, a rural area in Japan, and 724 subjects (386 females; mean age: 63.9 ± 10.4 years) were recruited. CP was defined as persistent pain lasting at least 3 months in any part of the body. Serum concentrations of 25(OH)D, a biomarker of the vitamin D status, were measured using a radioimmunoassay. A serum 25(OH)D level <20 ng/mL was defined as serum 25(OH)D deficiency. Drinking habits were assessed using a self-administered questionnaire. There were three choices, “rarely drink”, “sometimes” and “everyday”. Respondents who answered “rarely drink” were labelled as non-drinkers and the others as drinkers.

Results

The prevalence of CP was 40.6%. A significant interaction between CP and drinking habits on 25(OH)D concentrations was observed (p = 0.098). A one-way analysis of covariance was performed to compare 25(OH)D concentrations between the subjects with and without CP in each drinking group, and the serum 25(OH)D levels of subjects with CP were significantly lower than those without CP among drinkers (p = 0.007). A logistic regression analysis revealed a correlation between serum 25(OH)D deficiency and CP in drinkers after adjustments for several confounding factors (odds ratio: 0.499; 95% confidence interval: 0.268 − 0.927; p = 0.028).

Conclusion

The present results suggest that low serum 25(OH)D concentrations are associated with the development of CP in drinkers.