AB0097 TISSUE CYTOKINES AS NEW DIAGNOSTIC BIOMARKER OF BONE METABOLISM DISORDERS IN RHEUMATOID ARTHRITIS

Background:Bone mineral density and proteins/peptides determination in blood and urine as markers of bone resorption and formation are currently used to diagnose osteoporosis (OP) and metabolic bone diseases. Recent evidence suggests that in RA changes in the secretion of hormones of white adipose tissue can be revealed [1,2,3,4].Objectives:To study the clinical and diagnostic value of serum fetuin A, nesfatin, hemerin, leptin, adiponektin, resistin, visfatin determination in RA patients complicated by OP.Methods:We examined 88 women with documented diagnosis of RA and mean disease duration of 6.56±0.88 years. We used EULAR/ARA 2010 criteria to diagnose the patients. Female patients with II degree of disease activity (DAS28), Steinbrocker stage II (erosive), rheumatoid factor- and anti-cyclic-citrullinated peptide antibody-positive were prevalent. We excluded patients who had surgery or developed an infection within the last 8 weeks, pregnant and breast-feeding women, those with severe heart, liver or kidney disease, immune deficiency, leukopenia or chronic infection.A control group of 45 healthy females aged of 25 and 59 years were included in the study. There were no reported findings of joint pain and RA symptoms in the group. The groups were adjusted for age (p>0.05) and showed no statistically significant differences.We measured serum fetuin A, nesfatin, hemerin, leptin, adiponektin, resistin, visfatin levels (µg/ml) using ELISA commercial test systems. We used spectrophotometer with wavelength of 450 nm to detect the test results («Multiskan» immunoenzyme analyzer, Finland). We plotted a curve using computer software. We diagnosed OP using dual-energy X-ray absorptiometry with LUNAR DPX PRO (GE, USA).Results:At the first stage, the level of pro-inflammatory cytokines was studied in a group of healthy individuals. Then, the reference values of these indicators were measured as М ± 2δ. Patients with OP and RA had significantly higher levels of serum pro-inflammatory cytokines (р<0.001). For example, mean serum Adiponectin levels in RA patients who had normal bone density and had no OP were 35.21±0.6 µg/ml. Mean serum Adiponectin levels in RA/OP patients with low bone mineral density were 52.42±0.69 µg/ml. Adiponectin levels of 44 µg/ml and higher were associated with osteoporosis. Adiponectin levels of 43.9 µg/ml and lower were associated with normal bone density. Other pro-inflammatory cytokines have demonstrated similar dynamics of level serum.Conclusion:Thus, we revealed that fetuin A, nesfatin, hemerin, leptin, adiponektin, resistin, visfatin levels depend on osteoporosis presence in RA patients. The test may be used to reduce the risk of low-energy fractures and to improve the quality of life in RA.References:[1]Akhverdyan Y. et al. Laboratory markers of inflammation and serum nicotinamide phosphoribosyltransferase level in rheumatoid arthritis patients // Ann. Rheum. Dis., 2017, vol.76, suppl.2, p.1149.[2]Kvlividze Z. et al. Elevated nesfatin-1 levels in patients with rheumatoid arthritis // Ann Rheum Dis, 2018, vol.77, p.A1762.[3]Papichev E. et al. Fetuin-A: clinical and laboratory associations in women with rheumatoid arthritis // Ann Rheum Dis, 2018, vol.77, p.A1228.[4]Polyakova J. S. et al. Serum visfatin determination in rheumatoid arthritis // Ann. Rheum. Dis. 2014; 73 (Suppl2).Disclosure of Interests:None declared