title: Smoking and delay to diagnosis are associated with poorer functional outcome in psoriatic arthritis.
abstract: OBJECTIVE
  To identify predictors of poorer physical function in established psoriatic arthritis (PsA).
  
  
  METHODS
  PsA patients with disease duration of ≥10 years were identified from the Bath longitudinal cohort. Physical function was assessed using the Stanford Health Assessment Questionnaire (HAQ). Sex, age at diagnosis, duration of symptoms prior to diagnosis, smoking, treatment and year of diagnosis were included in a multivariable regression analysis to identify associations with HAQ.
  
  
  RESULTS
  267 patients were identified for inclusion. The median age was 56 years (IQR 45-63), median disease duration was 13 years (IQR 10-18) and median HAQ score was 0.63 (IQR 0.13-1.25). The model predicted significant increases in HAQ related to smoking (0.23, 95% CI 0.04 to 0.42), age >50 years at diagnosis (0.27, 95% CI 0.03 to 0.51), symptom duration of ≥1 year before diagnosis (0.22, 95% CI 0.02 to 0.42), female sex (0.39, 95% CI 0.20 to 0.57) and history of treatment with an anti-TNF agent (0.63, 95% CI 0.32 to 0.93) at follow-up.
  
  
  CONCLUSIONS
  Smoking, delay to diagnosis, older age at diagnosis, female sex and a history of anti-TNF treatment are associated with worse physical function in established PsA.
authors.affiliation: Department of Rheumatology, Royal National Hospital for Rheumatic Diseases, Bath, UK. w.tillett@nhs.net
authors.forename: William
authors.initials: W
authors.lastname: Tillett
authors.forename: Deepak
authors.initials: D
authors.lastname: Jadon
authors.forename: Gavin
authors.initials: G
authors.lastname: Shaddick
authors.forename: Charlotte
authors.initials: C
authors.lastname: Cavill
authors.forename: Eleanor
authors.initials: E
authors.lastname: Korendowych
authors.forename: Corinne S
authors.initials: CS
authors.lastname: de Vries
authors.forename: Neil
authors.initials: N
authors.lastname: McHugh
mesh_terms: D000367:Age Factors; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000627:therapeutic use; D015535:Arthritis, Psoriatic / Q000175:diagnosis* / Q000503:physiopathology / Q000534:rehabilitation*; D057210:Delayed Diagnosis / Q000009:adverse effects*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020127:Recovery of Function / Q000187:drug effects*; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha
keywords: Disease Activity; Outcomes research; Psoriatic Arthritis