title: Continuous long-term anti-TNF therapy does not lead to an increase in the rate of new bone formation over 8 years in patients with ankylosing spondylitis.
abstract: OBJECTIVE
  Compare the radiographic progression of ankylosing spondylitis (AS) patients treated with infliximab (INF) versus historical controls (Herne cohort, HC) never treated with tumour necrosis factor (TNF)-blockers over 8 years.
  
  
  METHODS
  Patients were selected based on the availability of lateral cervical and lumbar radiographs at baseline (BL) and after 8 years. Radiographs were scored by two blinded readers using modified Stokes AS spinal score (mSASSS). Mixed linear models were applied to compare radiographic progression between cohorts after adjustment for baseline status.
  
  
  RESULTS
  Patients in INF (n=22) and HC (n=34) did not differ in the mSASSS status: 13.2 ± 17.6 in INF versus 14.2 ± 13.8 in HC (p=0.254). Both showed progression at 8 years: mean mSASSS 20.2 ± 21.4 in INF and 25.9 ± 17.8 in HC. After adjustment for baseline damage the mean mSASSS (SEM) at 8 years was 21.0 (1.4) in INF and 25.5 (1.1) HC (p=0.047). The mean mSASSS difference was similar in the groups between baseline and 4 years but was more pronounced in HC between 4 and 8 years (p=0.03 between groups). The mean number of syndesmophytes, although similar at baseline, differed significantly at 8 years: 1.0 ± 0.6 new syndesmophytes/patient in INF versus 2.7 ± 0.8 in HC (p=0.007). Adjustment for age, symptom duration, HLA-B27, Bath AS disease activity index and Bath AS function index at baseline had no influence.
  
  
  CONCLUSIONS
  Despite limitations of patient numbers and retrospective study design, these data show increase in new bone formation in both patients treated with anti-TNF and those who did not. However, since there was even less bone formation in the INF treated group after 8 years, these data argue against a major role for the TNF-brake hypothesis.
authors.affiliation: Rheumazentrum Ruhrgebiet, Ruhr-University Bochum, , Herne, Germany.
authors.forename: Xenofon
authors.initials: X
authors.lastname: Baraliakos
authors.forename: Hildrun
authors.initials: H
authors.lastname: Haibel
authors.forename: Joachim
authors.initials: J
authors.lastname: Listing
authors.forename: Joachim
authors.initials: J
authors.lastname: Sieper
authors.forename: Jürgen
authors.initials: J
authors.lastname: Braun
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology; D018450:Disease Progression; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000069285:Infliximab; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010012:Osteogenesis / Q000187:drug effects*; D011859:Radiography; D012189:Retrospective Studies; D016037:Single-Blind Method; D013167:Spondylitis, Ankylosing / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab
keywords: Ankylosing Spondylitis; Anti-TNF; NSAIDs