ASSOCIATION BETWEEN ANTI CITRULLINATED PEPTIDES ANTIBODIES, BONE MINERAL DENSITY, AND FRACTURE RISK IN RHEUMATOID ARTHRITIS PATIENTS

Background: Recent literature reported Anti Citrullinated Peptides Antibodies (ACPA) associated with bone loss in patients with rheumatoid arthritis (RA). Objectives: To study if ACPA positivity was associated with bone mineral density and the ten-year probability of fracture (FRAX) in RA patients. Methods: We performed a cross-sectional study on patients with RA diagnosis according to ACR-EULAR 2010 classification recruited from January 2021 till January 2022. Patients aged from 40 to 90 years were included. Those with prior cancer, hyperparathyroidism, hyperthyroidism, diabetes, chronic kidney disease, and cirrhosis were excluded. Clinical data and results of laboratory tests were collected simultaneously with bone mineral density (BMD) acquisition. The latter was measured with dual-energy X-ray absorptiometry (DXA). BMD of the femoral neck (FN) was used to calculate the ten-year probability of major osteoporotic fracture (FRAX MOF) and femoral neck risk fracture (FRAX FN). Patients were grouped by positivity or quartile of ACPA level (I-IV). We used logistic regression, parametric and non-parametric tests for statistical analysis with SPSS20. Results: Eighty-two RA patients were enrolled. In total, 69 (84.1%) were women, 16 (19.5%) reported a previous personal fracture, and 37 (45.1%) had osteoporosis. Seventy-two (87.8%) patients were ACPA positive. The mean body mass index (BMI; kg/m ) and lumbar spine BMD in ACPA-positive patients were 25.44 ± 4.79 and 0.791 ± 0.138, respectively. We found a significant association between ACPA positivity and BMI over 25 (p = 0.01; OR = 0.132 [1.527; 6.785]). Comparison between ACPA positive/negative patients did not find a significant difference for osteoporosis, history of fracture, DAS28CRP, lumbar spine BMD, FN BMD, FRAX MOF BMD, and FRAX FN BMD. Lumbar spine BMD was significantly different (p = 0.035) among subgroups of ACPA levels, whereas there was no significant difference for FRAX MOF, FRAX FN, and FN BMD. Conclusion: In this study, lumbar spine BMD was significantly different among subgroups of ACPA levels. Disclosure of Interests: None declared. Citation: , volume 81, supplement 1, year 2022, page 543Session: Rheumatoid arthritis - prognosis, predictors and outcome (POSTERS only)