Background Vitamin D deficiency is common in Poland. Epidemiological data suggest that it may be a risk factor for development or aggravation of autoimmune diseases.
Some authors reported an inverse relationship between serum vitamin D metabolites concentration and disease activity, disability, pain and quality of life in patients with arthritis.
Objectives The aim of the study was to estimate the prevalence of vitamin D deficiency in rheumatoid arthritis (RA) patients in Poland and to assess the correlation between 25-hydroxyvitamin D (25(OH)D) serum concentration and disease activity, treatment schedule, disability, quality of life and mood disturbances.
Methods 113 RA patients (101 women,12men, mean age 59) were included in the study. Detailed information on previous treatment and vitamin D supplementation have been collected. The patients completed Short Form 36 Health Survey (SF-36), HAQ disability index and Beck Depression Inventory. Serum 25(OH)D, calcium, phosphorus and creatinine concentration have been performed in all patients. Disease Activity Score (DAS28) was used to evaluate disease activity.
Results 17 (15%) patients (early RA) received no RA treatment Other patients were on methotrexate(≥15 mg/week) monotherapy (22;19.5%), methotrexate combined with low doses of prednisone (43;38.1%) and prednisone alone (31; 27.4%). Vitamin D deficiency (<20ng/mL) was found in 83 (73,5%) patients. The prevalence of vitamin D deficiency was comparable in patients on vitamin D supplementation and patients without supplementation. Mean serum 25(OH)D concentration in patients with low disease activity (DAS28<3.2) was higher than in patients with high disease activity (DAS28>5.2) (16,2ng/mL vs14ng/mL), and similarly mean DAS28 was higher in vitamin D-deficient patients than in patients with adequate vitamin D serum concentration (4,2 vs 3,9), but the differences were insignificant.
The lowest 25(OH)D concentration was found in patients on prednisone monotherapy, the highest was observed in patients on methotrextate monotherapy (10,6 vs 17ng/mL; p=0,03). There was no correlation between vitamin D concentration and indices of life quality, disability, pain and depression.
Conclusions Vitamin D deficiency is common in RA patients and the supplementation seems inadequate in this group of patients. Glicocorticosteroid therapy is associated with aggravation of vitamin D deficiency; on the other hand adequate DMARD therapy (without steroids) seems to have beneficial effect. The possible negative correlation between disease activity and vitamin D concentration needs further studies on larger groups of patients.
Rossini M, Maddali Bongi S, La Montagna G et al. Vitamin D deficiency in rheumatoid arthritis: prevalence, determinants and associations with disease activity and disability. Arthritis Research&Therapy 2010;12:R216
Cutolo M, Otsa K, Uprus M et al. Vitamin D in rheumatoid arthritis. Autoimmunity Reviews 2007;7:59-64
Antico A. Toampoia M, Tozzoli R et al. Can supplementation with vitamin D reduce the risk or modify the course of autoimmune diseases? A systematic review of the literature. Autoimmunity Reviews 2012;12:127-136
Disclosure of Interest None Declared