Role of vitamin D in flare ups of rheumatoid arthritis

Rheumatoid arthritis (RA) is one of the most prevalent autoimmune diseases worldwide. Some researchers have suggested that the serum vitamin D (Vit D) level may relate to disease activity. The current study was designed to identify the correlation between vitamin D prescription and prevention of relapses in rheumatoid arthritis.

A double blinded, randomized controlled trial study was performed using 80 RA patients. RA was controlled and patients were in remission during the past 2 months. Serum level of Vit D in the studied patients was below 30 ng/dl. Patients were randomly allocated to receive Vit D or placebo. In the 6-month follow-up period, the Disease Activity Score 28 (DAS28) was used in case of relapses as an index of RA activity to compare the two groups.

The flare rate was not different between two groups (p > 0.05). The odds ratio of the rate of decline in patients of the trial group compared with the control group was 1.17 (not significant; p > 0.05). The mean DAS28 between the two patient groups was not significant (p > 0.05).

A low Vit D level was not identified to be a risk factor for RA severity or flare ups; however, although not statistically significant, Vit D treatment might be clinically effective. Further studies are needed with more emphasis on the issue of cost effectiveness and clinical importance to provide more information.