Evaluation of the relationship between vitamin D levels and related serum markers as well as disease activity in patients with rheumatoid arthritis: A cross-sectional study

Document Type : Original Article


1 Internal Medicine Department, School of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran

2 Cancer Epidemiology Research and Treatment Center, Emam reza hospital, Tehran, Iran

3 Liver and Digestive Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran

4 Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran

5 Student Research Committee, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

6 Shiraz University of Medical Sciences, Shiraz, Iran,

7 Colorectal research center, Shiraz University of Medical Sciences, Shiraz, Iran



Many studies have reported the role of vitamin D in autoimmune disease including rheumatoid arthritis (RA) which is related to several serum autoantibodies such as RF and Anti CCP. It also has been shown that vitamin D deficiency affect the DAS28 and VAS score inversely. Therefore, the aim of this study was to assess the relationship between vitamin D deficiency and RA-related autoantibodies including Anti CCP and RF levels and also evaluate the association between these parameters and the severity of rheumatoid arthritis.
Methods: In this cross-sectional study, RA patients over 16 years of age who refer to the clinic and rheumatology ward were enrolled. The severity of diseases was assessed via the DAS28 scoring system. Serum levels of 25(OH) vitamin D with other rheumatoid related laboratory evaluations including Anti CCP, RF and CRP were determined.
Results: A total of 100 patients with a mean age of 45.27± 14.14 were included; of them, 75% were female. Most of the patients (66%) had moderate DAS28 levels; however, no substantial relationship was observed between DAS28 and vitamin D levels. A significant inverse relation between serum 25(OH)D level and disease duration, as well as a significant positive correlation with the level of education, was observed.
Conclusion: Due to vitamin deficiency in the majority of cases (73%) and the relationship between 25(OH)D levels and the duration of disease, it can be concluded that vitamin D levels should be checked in those patients.