title: Reduction in Spinal Radiographic Progression in Ankylosing Spondylitis Patients Receiving Prolonged Treatment With Tumor Necrosis Factor Inhibitors.
abstract: To evaluate the course of spinal radiographic progression for up to 8 years of followup in a large cohort of ankylosing spondylitis (AS) patients treated with tumor necrosis factor (TNF) inhibitors.
  
  
  
  Consecutive patients from the Groningen Leeuwarden AS cohort starting TNF inhibitors between 2004 and 2012 were included. Baseline and biannual radiographs were randomized with radiographs of TNF-naive AS patients and scored in chronologic order according to modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). The course of radiographic progression (linear or nonlinear) was investigated using generalized estimating equations. Primary analysis was performed in patients with complete data over 4, 6, and 8 years of followup. Sensitivity analysis was performed after single linear imputation of missing radiographic data and after adjusting for patient characteristics with possible influence on radiographic progression.
  
  
  
  At baseline, median mSASSS of 210 included AS patients was 2.8 (interquartile range 0.0-12.0), mean ± SD mSASSS 10.0 ± 15.5. During the first 4 years, radiographic progression followed a linear course (estimated mean progression rate was 1.7 for 0-2 and 2-4 years). A deflection from a linear course was found in patients with complete and imputed data over 6 and 8 years. The estimated mean 2-year progression rate reduced from 2.3 to 0.8 in patients with complete 8-year data. The same pattern was found after adjustment for baseline mSASSS scores, presence of syndesmophytes, sex, HLA-B27 status, age, symptom duration, smoking duration, body mass index, disease activity, and nonsteroidal antiinflammatory drug use.
  
  
  
  This observational cohort study in AS patients receiving long-term TNF inhibitors showed a reduction in spinal radiographic progression after more than 4 years of followup.
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Fiona
authors.initials: F
authors.lastname: Maas
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, and Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Arends
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Brouwer
authors.affiliation: Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Ivette
authors.initials: I
authors.lastname: Essers
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Eveline
authors.initials: E
authors.lastname: van der Veer
authors.affiliation: Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: Monique
authors.initials: M
authors.lastname: Efde
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Peter M A
authors.initials: PMA
authors.lastname: van Ooijen
authors.affiliation: Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: Rinze
authors.initials: R
authors.lastname: Wolf
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Nic J G M
authors.initials: NJGM
authors.lastname: Veeger
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Hendrika
authors.initials: H
authors.lastname: Bootsma
authors.affiliation: Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: Freke R
authors.initials: FR
authors.lastname: Wink
authors.affiliation: University Medical Center Groningen, University of Groningen, Groningen, and Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: Anneke
authors.initials: A
authors.lastname: Spoorenberg
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D015331:Cohort Studies; D018450:Disease Progression; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography / Q000639:trends; D011897:Random Allocation; D013131:Spine / Q000000981:diagnostic imaging*; D013167:Spondylitis, Ankylosing / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000893:Anti-Inflammatory Agents; D014409:Tumor Necrosis Factor-alpha