title: Factors associated with a bad functional prognosis in early inflammatory back pain: results from the DESIR cohort.
abstract: BACKGROUND
  Spondyloarthritis (SpA) is a heterogeneous disease with hardly predictable potential courses. We aimed at determining prognostic factors of bad functional outcome at 2 years in patients with early inflammatory back pain (IBP).
  
  
  METHODS
  Data from patients included in the French multicentre devenir des spondylarthropathies indifférenciées récentes (DESIR) cohort, that is, suffering from IBP starting before 50 years of age and lasting for 3-36 months, were used. A bad functional outcome at 24 months was defined as an increase in bath ankylosing spondylitis functional index (BASFI), or BASFI at 2 years higher than the 75th centile in the cohort. Demographic, clinical, biological and radiological data collected at inclusion were compared in patients with bad functional outcome versus others, by χ(2) test, then by a multivariate logistic regression model with stepwise selection of relevant factors.
  
  
  RESULTS
  513 patients (54.4% females, 72.2% fulfilling ASAS criteria) were assessed. Of those, 130 (25.3%) fulfilled the aforementioned criteria of a bad functional outcome (BASFI increase ≥4 units or ≥36 at 2 years). Multivariate analysis revealed that not fulfilling ASAS criteria, female sex, age >33 years, lower educational level, active smoking status and high disease activity according to bath ankylosing spondylitis disease activity index (BASDAI) at baseline were independently associated with a bad functional outcome at 24 months. Sensitivity analyses restricted to patients fulfilling ASAS criteria for SpA resulted in similar results.
  
  
  CONCLUSIONS
  We observed, in a large prospective cohort of patients with early IBP, formerly described bad prognostic factors, especially a low educational level, an older age and a high disease activity at onset, and revealed that active smoking status and female sex were also independently associated with a poor outcome. Fulfilment of ASAS criteria, on the other hand, was predictive of a better outcome, most likely due to the more consensual management of a defined disease.
authors: Department of Rheumatology, University Hospital Lapeyronie, Montpellier, France; Montpellier University, Montpellier, France.
authors: C
authors: C
authors: Lukas
authors: Department of Rheumatology B , Cochin Hospital , Paris , France.
authors: M
authors: M
authors: Dougados
authors: Department of Rheumatology , University Hospital Lapeyronie, Montpellier University , Montpellier , France.
authors: B
authors: B
authors: Combe
keywords: Epidemiology; Patient perspective; Spondyloarthritis