NEGATIVE ASSOCIATION BETWEEN 25-HYDROXYVITAMIN D AND INFLAMMATORY MARKERS IN RHEUMATOLOGIC DISEASES

Objective The main purpose of this study was to evaluate serum 25-hydroxyvitamin D (250HD) levels and its association with inflammatory markers in patients with rheumatologic diseases (RD). Methods A cross-sectional study in 154 women with RD (rheumatoid arthritis, spondyloarthritis and other connective tissue diseases) and 112 healthy individuals as a control group (CG) was carried out. Results No differences in serum and urine calcium, serum phosphate, and urinary deoxypyridinoline were found. RD group had lower 250HD and higher PTH compared to CG. RD group had higher C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) compared to CG. The overall mean level of 250HD (ng/ml) was 26.3 +/- 12.0 in the CG and 19.4 +/- 6.8 in the RD group (p<0.0001). Moreover, CG had lower percentage of individuals with 250HD deficiency compared to RD (29.9% vs 53.2%). The femoral neck BMD was significantly lower in postmenopausal RD women compared to CG. 250HD levels significantly correlated with ESR and CRP as inflammatory markers. Age, BMI, presence of RD, and CRP were significantly and negatively associated with 250HD levels through linear regression analysis. According to univariate logistic regression analysis for 250HD deficiency (<20 ng/ml), a significant and negative association with BMI, presence of RD, ESR and CRP were found. Conclusion Patients with RD had lower 250HD levels than controls and the presence of a RD increases by 2.66 the risk of vitamin D deficiency. In addition, 250HD has a negative correlation with ESR and CRP as inflammatory markers.