Background In 2009 the Assessment of SpondyloArthritis international Society (ASAS) developed the new classification criteria for axial spondyloarthritis in a large cohort of patients with recent-onset low back pain.
Objectives To evaluated the value of ASAS criteria in distinguishing axial SpA patients from other back pain patients in a 2-year following-up study, comparing to ESSG criteria and Amor criteria.
Methods Patients with chronic back pain ≥3 months and age at onset before 45 were enrolled and clinical parameters were collected, especially the SpA features. On the first visit, patients were divided into two groups of fulfilling the ESSG criteria, Amor criteria or ASAS classification criteria or not. Final diagnosis of axial SpA and non-SpA were confirmed by rheumatologists after 2-year follow-up. Chi-square test was performed to test the association between the expert’s opinion and each set of classification criteria, respectively. P<0.05 was considered to be significantly difference.
Results Eight hundred and sixty-seven patients with chronic back pain were enrolled and diagnosed as 455 axial SpA patients and 412 non-SpA patients after 2-year follow-up. On the first visit, the ASAS criteria could distinguish more SpA patients than ESSG criteria and Amor criteria, and more non-SpA patients than ESSG criteria and Amor criteria. Chi-square test showed the ASAS criteria had better distinguishing coincidence (Kappa=0.7593) than both ESSG criteria (Kappa=0.5926) and Amor criteria (Kappa=0.6469).
Conclusions ASAS axial SpA classification criteria showed superior value to ESSG criteria and Amor criteria on diagnosing axial SpA patients from Chinese patients with chronic back pain.
Acknowledgements The study was supported by the grants of clinical subject (2007) of Ministry of public health of China and 5010 Subject of Sun Yat-sen University.
Disclosure of Interest None Declared