Vitamin D and rheumatoid arthritis: an ongoing mystery.

PURPOSE OF REVIEW: In recent years, there has been a growing interest in the value of vitamin D and its effects on autoimmunity. The aim of this review is to summarize the current knowledge on the association between vitamin D and rheumatoid arthritis (RA) in terms of prevalence, disease activity, clinical expression, serology and gene polymorphisms of vitamin D receptors. RECENT FINDINGS: Studies have shown contrasting findings concerning the association between vitamin D levels and RA. Vitamin D seems to have immunomodulatory properties. Therefore, low vitamin D levels could contribute to increased immune activation. However, the potential role of vitamin D supplementation in preventing RA manifestation and its beneficial role as a component of RA treatment remain controversial. The relationship between RA susceptibility and vitamin D polymorphisms is also unclear. SUMMARY: Despite advancements synthesized by some recent meta-analyses, the relationship between vitamin D and RA requires further evaluation. Further research is needed to confirm the relationship between RA susceptibility and vitamin D polymorphisms and to determine whether vitamin D plays a role in preventing the manifestation of RA. Finally, additional studies are required to determine the impact and optimal amount of vitamin D supplementation in the treatment of RA patients.

Coexistent malignant conditions in rheumatoid arthritis - A population-based cross-sectional study.

OBJECTIVES: The aim of this study was to evaluate if association exist between rheumatoid arthritis and malignant diseases. METHODS: A cross-sectional study was conducted comparing rheumatoid arthritis patients with age and gender matched controls regarding the proportion of patients with comorbid malignant conditions. Chi-square tests and t-tests were used for univariate analysis. A logistic regression model was used for multivariate analysis. The study was performed utilising the medical database of Clalit Health Services. RESULTS: The study group included 11 782 rheumatoid arthritis patients and 57 973 controls. The total proportion of malignancies was significantly higher in the study group than in the control group (21.4% vs 11.2%; P<.001). The disease for which there was the strongest association among patients with rheumatoid arthritis was non-Hodgkin's lymphoma (1.1% vs 0.6%; P<.01). After multivariate analysis, lung cancer was not found to be significantly associated with rheumatoid arthritis. CONCLUSION: Rheumatoid arthritis is associated with several malignant disorders, in particular non-Hodgkin's lymphoma. Appropriate measures for non-Hodgkin's lymphoma screening in this patient population should be considered.

Vitamin D and Systemic Lupus Erythematosus: Myth or Reality?

There is growing interest in the contribution of vitamin D deficiency to autoimmunity. Several studies have shown an association between low levels of vitamin D and autoimmune disorders, including multiple sclerosis, rheumatoid arthritis, type 1 diabetes, autoimmune thyroid diseases, celiac disease, and systemic lupus erythematosus (SLE). Vitamin D receptor ligands can mediate immunosuppressive effects. It has been suggested that low levels of this hormone contribute to the immune activation in lupus and other autoimmune diseases. This review updates and summarizes the literature on the association between vitamin D and SLE, and discusses the various correlations between vitamin D and SLE activity, clinical expressions, serology, and gene polymorphisms of vitamin D receptors.