RT Journal Article
SR Electronic
T1 Etanercept Increases Bone Mineral Density in Ankylosing Spondylitis, but Does Not Prevent Vertebral Fractures: Results of a Prospective Observational Cohort Study
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP jrheum.150857
DO 10.3899/jrheum.150857
A1 Maria A.C.  van der Weijden
A1 J. Christiaan  van Denderen
A1 Willem F.  Lems
A1 Michael T.  Nurmohamed
A1 Ben A.C.  Dijkmans
A1 Irene E.  van der Horst-Bruinsma
YR 2016
UL http://www.jrheum.org/content/early/2016/02/08/jrheum.150857.abstract
AB Objective Ankylosing spondylitis (AS) is characterized by chronic inflammation leading to ankylosis, but also to low bone mineral density (BMD) and vertebral fractures (VFx). Treatment with tumor necrosis factor-α blockers decreases inflammation and has shown to be effective in increasing BMD. We studied the effects of etanercept (ETN) on BMD and VFx in patients with AS after 2 years of treatment. Further, we studied changes in bone turnover markers and radiological damage. Methods Patients with active AS, treated with ETN for 2 years, were included. BMD lumbar spine and hip were measured at baseline and after 2 years, as well as radiological damage (modified Stoke Ankylosing Spondylitis Spinal Score with the addition of the thoracic spine), VFx (Genant method), and change in bone turnover markers. Results Forty-nine patients with AS were included. After 2 years of ETN, hip BMD increased by 2.2% (p = 0.014) and lumbar spine BMD by 7.0% (p < 0.001). The Bath Ankylosing Spondylitis Disease Activity Index decreased significantly (p < 0.001), as well as C-reactive protein and erythrocyte sedimentation rate (p < 0.001). Despite ETN therapy, the number of patients with VFx more than doubled (from 6 to 15 patients, p = 0.003). Also, the radiological damage increased significantly over time (from 12.1 to 18.5, p < 0.001); however, no significant change in bone turnover markers was found. Conclusion This prospective longitudinal observational cohort study showed that after 2 years of ETN, BMD of the hip and spine increased significantly, but the number of patients with VFx and the severity of VFx increased as well. Besides that, radiological progression, including the thoracic spine, increased significantly. Thus, the favorable bone-preserving effect is accompanied by unfavorable outcomes on VFx and radiological damage.