New criteria for inflammatory back pain in patients with chronic back pain: a real patient exercise by experts from the Assessment of SpondyloArthritis international Society (ASAS)
- J Sieper1,
- D van der Heijde2,
- R Landewé3,
- J Brandt4,
- R Burgos-Vagas5,
- E Collantes-Estevez6,
- B Dijkmans7,
- M Dougados8,
- M A Khan9,
- M Leirisalo-Repo10,
- S van der Linden3,
- W P Maksymowych11,
- H Mielants12,
- I Olivieri13,
- M Rudwaleit1
- 1Rheumatology, Medizinische Klinik I, Charité – Campus Benjamin Franklin, Berlin, Germany
- 2Leiden University Medical Center, Leiden, The Netherlands
- 3Maastricht University Medical Center, Maastricht, The Netherlands
- 4Rheumatology Private Practice, Berlin, Germany
- 5Rheumatology Department, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, University of Mexico City, Mexico City, Mexico
- 6University of Córdoba, Córdoba, Spain
- 7VU Medical Centre, Amsterdam, The Netherlands
- 8Hospital Cochin, Paris, France
- 9Case Western Reserve University, MetroHealth Medical Center, Cleveland, Ohio, USA
- 10University Central Hospital, Helsinki, Finland
- 11University of Alberta, Edmonton, Alberta, Canada
- 12University Hospital, Ghent, Belgium
- 13Ospedale San Carlo, Potenza, Italy
- Dr M Rudwaleit, Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin, Rheumatologie, Medizinische Klinik I, Hindenburgdamm 30, 12203 Berlin, Germany; martin.rudwaleit{at}charite.de
- Accepted 14 December 2008
- Published Online First 15 January 2009
Abstract
Objective: Inflammatory back pain (IBP) is an important clinical symptom in patients with axial spondyloarthritis (SpA), and relevant for classification and diagnosis. In the present report, a new approach for the development of IBP classification criteria is discussed.
Methods: Rheumatologists (n = 13) who are experts in SpA took part in a 2-day international workshop to investigate 20 patients with back pain and possible SpA. Each expert documented the presence/absence of clinical parameters typical for IBP, and judged whether IBP was considered present or absent based on the received information. This expert judgement was used as the dependent variable in a logistic regression analysis in order to identify those individual IBP parameters that contributed best to a diagnosis of IBP. The new set of IBP criteria was validated in a separate cohort of patients (n = 648).
Results: Five parameters best explained IBP according to the experts. These were: (1) improvement with exercise (odds ratio (OR) 23.1); (2) pain at night (OR 20.4); (3) insidious onset (OR 12.7); (4) age at onset <40 years (OR 9.9); and (5) no improvement with rest (OR 7.7). If at least four out of these five parameters were fulfilled, the criteria had a sensitivity of 77.0% and specificity of 91.7% in the patients participating in the workshop, and 79.6% and 72.4%, respectively, in the validation cohort.
Conclusion: This new approach with real patients defines a set of IBP definition criteria using overall expert judgement on IBP as the gold standard. The IBP experts’ criteria are robust, easy to apply and have good face validity.
Footnotes
-
Competing interests: None declared.
-
Funding: The ASAS workshop in Berlin as well as the international study on new classification criteria for axial SpA are official ASAS scientific projects, financially supported by ASAS.
-
Ethics approval: The study was approved by the local ethical committee and informed consent was obtained from all patients.








