Karima Boussoualim1, Adamah Amouzougan1, Beatrice Pallot-Prades1, Delphine Denarié1, Philippe Collet1, Hubert Marotte1, Thierry Thomas2. 1. Rheumatology Department, CHU de St-Etienne, 42055 Saint-Etienne cedex 2, France. 2. Rheumatology Department, CHU de St-Etienne, 42055 Saint-Etienne cedex 2, France; INSERM U1059, Laboratoire de Biologie Intégrée du Tissu Osseux, 42055 Saint-Etienne cedex 2, France; Rheumatology Department, Université de Lyon, University Hospital of Saint-Etienne, 42055 Saint-Etienne cedex 2, France. Electronic address: thierry.thomas@chu-st-etienne.fr.
Abstract
OBJECTIVE: Many patients with spondyloarthritis (SpA) are at risk of fracture due to bone fragility, whereas their bone mineral density (BMD) is not significantly diminished. Other tools, such as trabecular bone score (TBS), evaluating other characteristics of bone tissue are therefore necessary in order to evaluate bone changes in these patients. Therefore we evaluated TBS as a bone quality marker, in a cohort of patients with SpA and investigated which clinical and biological factors were correlated with TBS values. METHODS: Patients fulfilling ASAS criteria of SpA with a BMD assessment and visiting our department for initiation or switch of a biologic treatment were selected. The clinical and biological data were collected at the time of BMD measurement. RESULTS: Ninety-five patients were included in the study, with a mean age of 40.2 and a mean disease duration of 8.2 years. Lumbar BMD T-score was <-1 and <-2.5 in 17% and 3% of patients, respectively. On average, TBS value was 1.34±0.12. Lumbar BMD was positively correlated with TBS (r=0.61), while disease duration, disease activity score and serum PTH levels were negatively correlated with TBS (r=-0.24, r=-0.33, and r=-0.27, respectively). These correlations persisted in a multivariate analysis. Furthermore, more than half of the patients with a BMD level above -2.5 T-score had a low TBS value. CONCLUSION: Our results show that TBS provides information additional to BMD on the bone status of patients with SpA. They suggest that TBS may help in identifying those patients at risk of fracture.
OBJECTIVE: Many patients with spondyloarthritis (SpA) are at risk of fracture due to bone fragility, whereas their bone mineral density (BMD) is not significantly diminished. Other tools, such as trabecular bone score (TBS), evaluating other characteristics of bone tissue are therefore necessary in order to evaluate bone changes in these patients. Therefore we evaluated TBS as a bone quality marker, in a cohort of patients with SpA and investigated which clinical and biological factors were correlated with TBS values. METHODS:Patients fulfilling ASAS criteria of SpA with a BMD assessment and visiting our department for initiation or switch of a biologic treatment were selected. The clinical and biological data were collected at the time of BMD measurement. RESULTS: Ninety-five patients were included in the study, with a mean age of 40.2 and a mean disease duration of 8.2 years. Lumbar BMD T-score was <-1 and <-2.5 in 17% and 3% of patients, respectively. On average, TBS value was 1.34±0.12. Lumbar BMD was positively correlated with TBS (r=0.61), while disease duration, disease activity score and serum PTH levels were negatively correlated with TBS (r=-0.24, r=-0.33, and r=-0.27, respectively). These correlations persisted in a multivariate analysis. Furthermore, more than half of the patients with a BMD level above -2.5 T-score had a low TBS value. CONCLUSION: Our results show that TBS provides information additional to BMD on the bone status of patients with SpA. They suggest that TBS may help in identifying those patients at risk of fracture.