title: Disease activity is longitudinally related to sacroiliac inflammation on MRI in male patients with axial spondyloarthritis: 2-years of the DESIR cohort.
abstract: OBJECTIVE
  To investigate the longitudinal relationship between inflammatory lesions in sacroiliac joints on MRI (MRI-SI) and clinical disease activity measures (DA) in patients with axial spondyloarthritis (axSpA).
  
  
  METHODS
  Two-year follow-up data from 167 patients (50% males, mean (SD) age 33 (9) years) fulfilling the Assessment of SpondyloArthritis international Society axSpA criteria in the DEvenir des Spondylarthopathies Indifférenciées Récentes cohort with MRI-SI at baseline, 1 year and 2 years were analysed. The relationship between MRI-SI (as dependent variable) and DA (Ankylosing Spondylitis Disease Activity Score (ASDAS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), patient's global DA, night pain, C reactive protein and erythrocyte sedimentation rate, as independent variables) was investigated using two types of generalised estimating equations (GEE) models: model of absolute scores and model of change scores.
  
  
  RESULTS
  In the model of absolute scores, the relationship between DA and MRI-SI was different for males and females: in males, but not in females, a statistically significant relationship with MRI-SI was found for all DA except BASDAI. In the model of changes, only ASDAS (beta (95% CI): 2.79 (0.85 to 4.73) and pain at night (0.97 (0.04 to 1.90)) were significantly associated in males while again in females no significant relationship was found. ASDAS fitted the data best.
  
  
  CONCLUSIONS
  In male patients, but not in female patients, with axSpA, clinical DA, especially if measured by ASDAS, is longitudinally associated with MRI-SI inflammatory lesions.
authors.affiliation: Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands Department of Rheumatology, University Hospital La Paz, IdiPaz, Madrid, Spain.
authors.forename: Victoria
authors.initials: V
authors.lastname: Navarro-Compán
authors.affiliation: Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Sofia
authors.identifier: http://orcid.org/0000-0002-8899-9087
authors.initials: S
authors.lastname: Ramiro
authors.affiliation: Department of Clinical Immunology & Rheumatology, Amsterdam Rheumatology & Clinical Immunology Center, University of Amsterdam, Amsterdam, The Netherlands Department of Rheumatology, Atrium Medical Center, Heerlen, The Netherlands.
authors.forename: Robert
authors.initials: R
authors.lastname: Landewé
authors.affiliation: Department of Rheumatology, Paris Descartes University, Cochin Hospital, Assistance Publique-Hôpitaux de Paris, INSERM: Clinical Epidemiology and Biostatistics, PRES Sorbonne Paris-Cité, Paris, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: Dougados
authors.affiliation: Department of Rheumatology, Hôpitaux Universitaires Paris-Sud, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Miceli-Richard
authors.affiliation: Université Paris Diderot, UFR médicale, Paris, France; APHP Hôpital Lariboisiére, Fédération de Rhumatologie, Paris, France Inserm U1132, Hôpital Lariboisière, Paris, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Richette
authors.affiliation: Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Désirée
authors.identifier: http://orcid.org/0000-0002-5781-158X
authors.initials: D
authors.lastname: van der Heijde
mesh_terms: D000328:Adult; D001416:Back Pain / Q000209:etiology; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D012446:Sacroiliac Joint / Q000473:pathology; D058566:Sacroiliitis / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D012720:Severity of Illness Index; D012737:Sex Factors; D025241:Spondylarthritis / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein
keywords: Ankylosing Spondylitis; Inflammation; Spondyloarthritis