title: Relationship of bone mineral density with disease activity and functional ability in patients with ankylosing spondylitis: a cross-sectional study.
abstract: In ankylosing spondylitis, inflammatory activity probably plays a key role in the pathophysiology of bone loss. The aim of the study was to investigate the relationship of bone mineral density (BMD) at the lumbar spine and hip region with some measures of disease activity and functional ability in patients with ankylosing spondylitis. In 80 patients with established ankylosing spondylitis, disease activity and functional ability were determined by C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI). Spinal pain and patient global health were assessed using horizontal visual analog scale. BMD was measured by dual-energy X-ray absorptiometry. There was a significant negative correlation of bone density T scores with acute-phase reactants (i.e., patients with lower T scores had higher level of CRP and ESR). That relationship was reflected more reliably at proximal femur sites than at the lumbar spine. There were also significant differences in ESR, BASDAI, BASFI, spinal pain and global health between three groups of patients according to WHO classification of osteoporosis (normal, osteopenic and osteoporotic). Significantly, more patients with osteopenia at the lumbar spine had lower BASDAI index than those with normal BMD (P = 0.030). Our results indicate an association of low BMD with high disease activity in patients with AS. Femoral BMD seems to be more associated with disease activity and functional ability than lumbar spine BMD.
authors.affiliation: University Department of Rheumatology, Physical and Rehabilitation Medicine, Sisters of Mercy University Hospital Centre, Referral Centre for Spondyloarthropathies of the Ministry of Health and Social Welfare Republic of Croatia, Vinogradska 29, 10000 Zagreb, Croatia. simeon.grazio@zg.t-com.hr
authors.forename: Simeon
authors.initials: S
authors.lastname: Grazio
authors.forename: Zvonko
authors.initials: Z
authors.lastname: Kusić
authors.forename: Selma
authors.initials: S
authors.lastname: Cvijetić
authors.forename: Frane
authors.initials: F
authors.lastname: Grubišić
authors.forename: Antonija
authors.initials: A
authors.lastname: Balenović
authors.forename: Tomislav
authors.initials: T
authors.lastname: Nemčić
authors.forename: Valentina
authors.initials: V
authors.lastname: Matijević-Mikelić
authors.forename: Marija
authors.initials: M
authors.lastname: Punda
authors.forename: Joachim
authors.initials: J
authors.lastname: Sieper
mesh_terms: D000328:Adult; D001799:Blood Sedimentation; D015519:Bone Density / Q000502:physiology*; D001851:Bone Diseases, Metabolic / Q000453:epidemiology / Q000209:etiology; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005260:Female; D005272:Femur Neck / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000453:epidemiology / Q000209:etiology; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000097:blood / Q000150:complications / Q000503:physiopathology*
chemical_list: D002097:C-Reactive Protein