Bone mineral density in women with rheumatoid arthritis: A link between immune and biochemical markers

Aim. To study the association of bone mineral density (BMD) with serum biochemical and immunological markers in postmenopausal women with rheumatoid arthritis (RA). Materials and methods. The study included 173 women with RA (age 61.0 [56.0; 66.0] years). A survey, dual -energy X-ray absorptiometry to measure the BMD of the lumbar spine (L I -L IV ), femoral neck (FN) and total hip (TH), routine blood chemistry, measurement of C -reactive protein (CRP), rheumatoid factor, cyclic citrullinated peptide antibodies (CCPA), parathyroid hormone (PTH), vitamin D 3 , myostatin, follistatin, interleukin-6 (IL -6), IL -6 receptors, insulin -like growth factor 1, adiponectin, leptin, fibroblast growth factor 23, and tumor necrosis factor SF12 were performed. Results. PTH ([3=-0.22, -0.35 and -0.30 for L I -L IV , FN and TH, respectively), CRP ([3=-0.18, 0.23 and -0.22 for L I -L IV , FN and TH, respectively) and leptin ([3=0.35, 0.32 and 0.42 for L I -L IV , FN and TH, respectively) were shown a significant association with BMD in all sites of measurement. It was independent of age, body mass index and postmenopause duration. Associations were also found between adiponectin and BMD of L I -L IV and TH ([3=-0.36 and -0.28, respectively), CCPA and BMD of FN and TH ([3=-0.21, -0.24, respectively) and IL -6 and BMD of FN ([3=0.37). Conclusion. The study of biochemical and immunological markers in women with RA demonstrated that CRP, CCPA, PTH, IL -6, adiponectin, and leptin influenced BMD.