title: Smokers in early axial spondyloarthritis have earlier disease onset, more disease activity, inflammation and damage, and poorer function and health-related quality of life: results from the DESIR cohort.
abstract: OBJECTIVE
  To investigate the association of smoking with various clinical, functional and imaging outcomes in patients with early axial spondyloarthritis (SpA).
  
  
  METHODS
  647 patients with early inflammatory back pain (IBP) fulfilling at least one of the internationally accepted SpA criteria and with available smoking data were included in the analyses. Clinical, demographic and imaging parameters were compared between smokers and non-smokers at a cross-sectional level. Variables with significant differences in univariate analyses were used as dependent variables in multivariate linear and logistic regression models adjusted for potential confounding/contributing factors.
  
  
  RESULTS
  Multivariate analysis showed that smoking was associated with an earlier onset of IBP (regression coefficient (B)=(-1.46), p=0.04), higher disease activity (ankylosing spondylitis disease activity score B=0.20, p=0.03; Bath ankylosing spondylitis disease activity index B=0.50, p=0.003), worse functional status (Bath ankylosing spondylitis functional index B=0.38, p=0.02), more frequent MRI inflammation of the sacroiliac joints (OR 1.57, p=0.02) and the spine (OR 2.33, p<0.001), more frequent MRI structural lesions of the sacroiliac joints (OR 1.54, p=0.03) and the spine (OR 2.02, p=0.01), and higher modified Stoke ankylosing spondylitis spine score (B=0.54, p=0.03) reflecting radiographic structural damage of the spine. Smoking was also associated with poorer quality of life (Euro-quality of life questionnaire B=1.38, p<0.001, short form 36 physical B=(-4.89), p<0.001, and mental component score B=(-5.90), p<0.001).
  
  
  CONCLUSIONS
  In early axial SpA patients, smoking was independently associated with earlier onset of IBP, higher disease activity, increased axial inflammation on MRI, increased axial structural damage on MRI and radiographs, poorer functional status and poorer quality of life.
authors: Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands.
authors: Ho Yin
authors: HY
authors: Chung
authors: Pedro
authors: P
authors: Machado
authors: Désirée
authors: D
authors: van der Heijde
authors: Maria-Antonietta
authors: MA
authors: D'Agostino
authors: Maxime
authors: M
authors: Dougados
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D017668:Age of Onset; D001416:Back Pain / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D011788:Quality of Life; D012307:Risk Factors; D012446:Sacroiliac Joint / Q000473:pathology; D012720:Severity of Illness Index; D012907:Smoking / Q000453:epidemiology*; D013167:Spondylitis, Ankylosing / Q000453:epidemiology* / Q000276:immunology / Q000473:pathology; D055815:Young Adult