Pos0506 risk factor analysis of fractures in patients with rheumatoid arthritis

Background Patients with rheumatoid arthritis (RA) commonly develop osteoporosis and fragility fractures due to differentiation and induction of osteoclast, steroid use, and inactivities of daily life [1-3] . The prevalence of osteoporosis during long-term RA has been reported to be as high as 19-32%, and RA patients have 1.5-2.3 times the risk of fracture as non-RA patients. However, the relationship between bone mineral density and fracture risk in RA patients is not clear, and there are few reports on bone mineral density and fracture location in RA patients. Objectives To investigate the incidence of fracture and fracture site in RA patients, and to explore the risk factors for fragility fractures in RA patients. Methods: 1. A total of 4785 RA patients were included. We extracted new incidence of fracture from medical record and investigated the location of fractures. 2. A total of 4270 patients including non-RA patients who had dual-energy X-ray absorptiometry (DEXA) were analyzed. The RA group was divided into two groups: RAfx+ group with fracture and RAfx- group without fracture. Young Adult Mean (YAM) values were compared between groups based on DEXA data from 3634 patients in the non-RA group, 147 patients in the RAfx+ group, and 489 patients in the RAfx- group. 3. The demographics, and clinical characteristics of 636 RA patients who had DEXA were investigated. Bone mineral density (YAM value), osteoporosis treatment intervention, steroid use, biologic drug use, the levels of anti-CCP (cyclic citrullinated peptide) antibody, and BMI (body mass index) were analyzed between two groups. Results: 1. Of the 4785 RA patients, a total of 550 fractures occurred in 384 patients (8.0%). The mean age was 70.5 and 63 years old in the fracture and non-fracture groups, respectively, and was significantly higher in the fracture group (p<0.01). The most common fracture sites were vertebral (205 fractures), following 57 proximal femur fractures, 55 thoracic fractures, and 41 pelvic fractures. 2. The %YAM of femur was 73.9% in the non-RA group, 67.7% in the RAfx+ group, and 76.0% in the RAfx- group, and %YAM of lumber spine was 85.5% in the non-RA group, 81.0% in the RAfx+ group, and 88.1% in the RAfx- group, with the RAfx+ group having significantly lower values (p < 0.01). After age and sex matching, 147 patients were allocated to each group, respectively. Young adult mean (YAM) values of femur were 67.7/73.7% and those of lumbar spine were 81.0/86.0% in group A/B, both of which were significant (p<0.01, 0.01, respectively). 3. In univariate analysis, a history of osteoporosis intervention, especially denosumab use, and a history of steroid use were associated with fracture incidence (p = 0.02, 0.002, 0.03, respectively) significantly. In multivariate analysis, YAM value of femur (OR: 0.386), a history of steroid use (OR: 2.04), and osteoporosis intervention (OR: 0.413) were significantly associated with the incidence of fractures. Conclusion New fractures occurred in 8.0% of RA patients, with vertebral fractures being the most common. RA patients with fractures had significantly lower femoral/lumbar YAM values than RA patients without fractures. steroid use, low femoral bone density, and lack of osteoporosis intervention were factors significantly associated with fracture occurrence in RA patients. References [1]Nakano K, Okada Y, Tanaka Y. Secondary osteoporosis. Bone metabolic disorder in Rheumatoid arthritis. Clin Calcium. 2018;28(12):1599-1603. [2]Xue AL, Wu SY, Jiang L, et al. Bone fracture risk in patients with rheumatoid arthritis: A meta-analysis. Medicine (Baltimore). 2017 Sep;96(36):e6983. [3]Fardellone P, Salawati E, Le Monnier L,et al. Bone Loss, Osteoporosis, and Fractures in Patients with Rheumatoid Arthritis: A Review. J Clin Med. 2020 Oct 20;9(10):3361. Acknowledgements: NIL. Disclosure of Interests None Declared.