Ab0951 Could There Be Gender-Specific Discriminative Features for Axial Spondyloarthritis and Inflammatory Back Pain Characteristics in Particular?

Background: Inflammatory back pain (IBP) is one of the key clinical symptom of the diagnosis and classification of axial spondyloarthritis (axSpA). However, sensitivity and specificity for axSpA alone may be limited. It has been reported that female patients with axSpA might have experience longer diagnostic delay and more frequent visit to general practitioners, physiotherapists and osteopaths before being diagnosed. Additionally, gender may have an impact on the discriminative performance of the IBP criteria sets as well as on the some individual IBP items. Objectives: In the present study we aimed to evaluate gender specific differences regarding the clinicial features of axSpA, individual IBP characteristics and criteria sets in a specific population consisting of axSpA patients and patients with IBP according to the treating physician. Methods: In total 673 patients (568 patients classified as axSpA according to ASAS criteria and 105 patients referred with IBP and the suspicion of SpA) were included in this analysis. IBP group consists patients with IBP according to treating physician, however they could not be classified as axSpA. Demographic, clinical and disease related data were obtained by standardized questionnaire. A BASDAI score of ≥4 and ASDAS-CRP value of ≥2.1 was used to definition of active disease. Results: Gender specific demographic and clinical characteristics summarized in Table 1. HLA-B27 positivity was higher in male patients with both axSpA and IBP only, however family history of SpA was more frequent in female patients. Although female axSpA and IBP only patients reported higher BASDAI scores and active disease according to BASDAI, ASDAS scores were similar in both gender. In contrast CRP levels were higher in male axSpA patients. As expected a significant proportion of IBP only group of patients also met IBA classification criteria (Table 2). Similar proportion of female and male patients (both in axSpA and IBP group) met Calin and Berlin criteria for IBP, however significiantly higher proportion of female axSpA patients fulfilled ASAS criteria in comparison with IBP group. In the evaluation of IBP characteristics, we found that improvement with exercise and alternating gluteal pain items of IBP were significantly higher in female axSpA patients in comparison with female nonSpA patients. However, awakening in the second half due to pain item was significantly higher in male axSpA patients. Conclusion: The results of the present study showed that even in patients with IBP according to physician there could be some differentiating factors for the diagnosis of axSpA. Also our results revealed that gender might have an impact not only for the diagnosis axSpA but also IBP. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.