title: Impaired response to treatment with tumour necrosis factor α inhibitors in smokers with axial spondyloarthritis.
abstract: OBJECTIVE
  To investigate the impact of smoking on the response to treatment with a first tumour necrosis factor inhibitor (TNFi) in patients with axial spondyloarthritis (axSpA) in a real-life cohort.
  
  
  METHODS
  Patients fulfilling the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA in the Swiss Clinical Quality Management Cohort were included in this study. The potential association between smoking status and differential response to TNFi in terms of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS) was analysed using multiple adjusted longitudinal mixed effect models. Binary response rates at 1 year were assessed with multiple adjusted logistic analyses.
  
  
  RESULTS
  A first TNFi was initiated in 698 patients with axSpA with available smoking status and a baseline or follow-up BASDAI assessment, of which 490 (70%) had complete covariate data. In comparison to non-smokers, current smokers demonstrated significantly smaller reductions in BASDAI and ASDAS scores upon treatment with TNFi (0.75 BASDAI units and 0.69 ASDAS units less, p=0.005 and 0.001, respectively) for patients with elevated baseline C-reactive protein (CRP) level. This effect was numerically smaller in patients with normal CRP. The odds for reaching a 50% improvement in BASDAI response or the ASAS criteria for 40% improvement after 1 year were significantly lower in current smokers than in non-smokers (0.54, 95% CI 0.31 to 0.95, p=0.03 and 0.43, 95% CI 0.24 to 0.76, p=0.004, respectively).
  
  
  CONCLUSIONS
  Current smoking is associated with an impaired response to TNFi in axSpA.
authors: Department of Rheumatology, University Hospital, Zurich, Switzerland.
authors: Adrian
authors: A
authors: Ciurea
authors: Swiss Clinical Quality Management Foundation, Zurich, Switzerland.
authors: Almut
authors: A
authors: Scherer
authors: King Christian 10th Hospital for Rheumatic Diseases, Gråsten, Denmark.
authors: Ulrich
authors: U
authors: Weber
authors: Private Rheumatology Practice, Basel, Switzerland.
authors: Pascale
authors: P
authors: Exer
authors: Department of Rheumatology and Rehabilitation, Bürgerspital, Solothurn, Switzerland.
authors: Jürg
authors: J
authors: Bernhard
authors: Department of Rheumatology, Bethesda Hospital, Basel, Switzerland.
authors: Giorgio
authors: G
authors: Tamborrini
authors: Swiss Clinical Quality Management Foundation, Zurich, Switzerland.
authors: Myriam
authors: M
authors: Riek
authors: Department of Rheumatology, Cantonal Hospital, St. Gallen, Switzerland.
authors: Rüdiger B
authors: RB
authors: Müller
authors: Division of Rheumatology, Uniklinik Balgrist, Zurich, Switzerland.
authors: Bettina
authors: B
authors: Weiss
authors: Department of Rheumatology, University Hospital, Geneva, Switzerland.
authors: Michael J
authors: MJ
authors: Nissen
authors: Division of Rheumatology, Uniklinik Balgrist, Zurich, Switzerland.
authors: Rudolf
authors: R
authors: Kissling
authors: Department of Rheumatology, University Hospital, Zurich, Switzerland.
authors: Beat A
authors: BA
authors: Michel
authors: Department of Rheumatology, University Hospital, Geneva, Switzerland.
authors: Axel
authors: A
authors: Finckh
mesh_terms: D000068879:Adalimumab / Q000627:therapeutic use; D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D000068582:Certolizumab Pegol / Q000627:therapeutic use; D000068800:Etanercept / Q000627:therapeutic use; D005260:Female; D006801:Humans; D000069285:Infliximab / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D012907:Smoking / Q000453:epidemiology*; D025242:Spondylarthropathies / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology; D013167:Spondylitis, Ankylosing / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein; C529000:golimumab; D000069285:Infliximab; D000068879:Adalimumab; D000068800:Etanercept; D000068582:Certolizumab Pegol
keywords: Ankylosing Spondylitis; Disease Activity; Smoking; Spondyloarthritis