SAT0484 TRABECULAR BONE SCORE IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS
Authors: A. Casabella, S. Paolino, E. Alessandri, V. Smith, B. Ruaro, C. Pizzorni, A. Sulli, M. Cutolo
Journal: Annals of the Rheumatic Diseases (2020)

Background: Systemic lupus erythematosus (SLE) patients shown an increased risk of low bone mass as a result of multifactorial events: physical inactivity, persistent inflammation, low vitamin D levels (photosensitivity) and glucocorticoid treatment. Trabecular Bone Score (TBS), is an index extracted from the dual-energy X-ray absorptiometry (DXA) that provides an indirect measurement of bone axial microarchitecture and allows to get information about bone quality in several rheumatic diseases (1-4). Objectives: The aims of this study were to examine the prevalence and risk factors for low bone mineral density (BMD) (osteoporosis or osteopenia) in female patients affected by SLE and to compare with matched healthy subjects (CNT). Methods: 70 female patients (mean age 41±20 years) affected by SLE and 65 age- matched CNT (mean age 46±7 years) were enrolled. Bone Mineral Density (BMD, g/cm2) of the lumbar spine (L1-L4) was analyzed using a DXA scan (GE, Lunar Prodigy). Lumbar spine TBS was derived for each spine DXA examination using the TBS index (TBS iNsight Medimaps). Results: The mean BMD±SD was 0.47±0.57 g/cm2 at the lumbar spine and 0.78 ± 0.22 g/cm2 at the hip in SLE patients. The prevalence of osteopenia was 40.0% and was 19.4% of osteoporosis in SLE patients. Most of SLE patients (75%) presented a bone loss that was significantly higher when compared with control group (p&lt;0.001). Lumbar spine TBS score was found significantly lower in SLE patients compared with CNT (0.687±0.675 vs, 1.294±0.809 p&lt;0.001, respectively) and of 0,47±0,94 times lower than expected from the concomitant reference BMD value. Conclusion: The study shows that the further TBS analysis, independently from the concomitant BMD value, is significatively lower then expected in SLE patients. The detection of the TBS, together with the BMD, may offer a more reliable indication of the real whole bone condition in chronic and systemic inflammatory rheumatic diseases, such as SLE. References: [1]Cutolo M et al. Ann Rheum Dis. 2009;68 446-7; 2 Dey M et al. Lupus. 018;271547-1551; 3 Ruaro B, Casabella A, et al. Rheumatology (Oxford). 2018;57:1548-1554. 4 Ruaro B, Casabella A, et al. Clin Rheumatol. 2018 Nov;37(11):3057-3062. Disclosure of Interests: Andrea Casabella: None declared, Sabrina Paolino: None declared, Elisa Alessandri: None declared, Vanessa Smith Grant/research support from: The affiliated company received grants from Research Foundation - Flanders (FWO), Belgian Fund for Scientific Research in Rheumatic diseases (FWRO), Boehringer Ingelheim Pharma GmbH &amp; Co and Janssen-Cilag NV, Consultant of: Boehringer-Ingelheim Pharma GmbH &amp; Co, Speakers bureau: Actelion Pharmaceuticals Ltd, Boehringer-Ingelheim Pharma GmbH &amp; Co and UCB Biopharma Sprl, Barbara Ruaro: None declared, Carmen Pizzorni: None declared, Alberto Sulli Grant/research support from: Laboratori Baldacci, Maurizio Cutolo Grant/research support from: Bristol-Myers Squibb, Actelion, Celgene, Consultant of: Bristol-Myers Squibb, Speakers bureau: Sigma-Alpha