THU0390 Clinical Characteristics of Spondyloarthritis in Japanese Patients
Authors: C. Min, K. Yoshida, Y. Haji, H. Inoue, Y. Kaneko, T. Kawasaki, K. Matsui, M. Morita, K. Tada, N. Takizawa, N. Tamura, N. Ichikawa, Y. Taniguchi, S. Tsuji, M. Okada, S. Kobayashi, T. Tomita, M. Kishimoto
Journal: Annals of the Rheumatic Diseases (2016)

<h3>Background</h3> Spondyloarthritis (SpA) has been considered relatively rare in Japan, with an estimated incidence rate of 0.48/100,000 person-years and an estimated population prevalence of less than 0.01%. However, in daily practice, we have diagnosed SpA more frequently after recent increase in awareness of this disease entity, suggesting presence of potentially severe under-diagnosis in the previous time periods. Further improvement of awareness of this disease entity is necessary to allow patients to receive appropriate treatments. In this study, we aim to characterize distinguishing clinical features of SpA in Japanese patients, which should then allow us to improve both under-diagnosis and misdiagnosis of this increasingly treatable disease entity. <h3>Objectives</h3> To evaluate clinical characteristics commonly manifested in Japanese SpA patients in COMOSPA database. <h3>Methods</h3> Descriptive statistics of patient demographics and clinical characteristics of SpA were provided in the Japanese subgroup comparing with those in rest of Asian countries and non-Asian countries. Prevalence of characteristics were compared across regions using ANOVA (continuous variables) or χ<sup>2</sup> test (categorical variables) to identify clinical features that were more characteristic of Japanese SpA patients. These analyses were conducted using the COMOSPA database. <h3>Results</h3> 161 Japanese patients, 933 non-Japanese Asian patients, and 2890 non-Asian patients were included in the study. Mean age and male percentage for Japanese patients were 48.9 years old and 59.3%, respectively. As a baseline characteristic, Japanese patients weighed less than other groups (65.0 vs. 66.6 vs. 78.3kg, p&lt;0.001). Radiographic axial SpA patients were significantly fewer in Japanese patients (50.9 vs. 76.4 vs. 61.1%, p&lt;0.001). Percentage of the patients with inflammatory back pain was lower in Japanese patients (71.9 vs. 88.6 vs. 85.1%, p&lt;0.001) as well. In contrast, peripheral arthritis consistent with SpA was more common in Japanese patients (75.0 vs. 46.2 vs. 63.6%, p&lt;0.001), as well as dactylitis (26.9 vs. 7.2 vs. 17.6%, p&lt;0.001), enthesitis (48.1 vs. 23.5 vs. 42.1%, p&lt;0.001) and nail involvements (25.5 vs. 3.3 vs. 13.5%, P&lt;0.001). Psoriasis was also more common in Japanese patients (38.5 vs. 6.2 vs. 20.0%, p&lt;0.001). HLA-B27 was less frequently positive in Japanese patients (29.2 vs. 80.0 vs. 49.9%, p&lt;0.001). Functional status measured by BASFI (Bath Ankylosing Spondylitis Functional Index) and disease activity measured by BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) tended to be lower in Japanese patients compared to non-Asian patients. <h3>Conclusions</h3> Japanese SpA patients demonstrated unique clinical pictures compared to other Asian and non-Asian countries. These results allow us to improve both under-diagnosis and misdiagnosis of the disease. <h3>Disclosure of Interest</h3> C. Min Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, K. Yoshida Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, Y. Haji Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, H. Inoue Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, Y. Kaneko Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, T. Kawasaki Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, K. Matsui Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, M. Morita Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, K. Tada Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, N. Takizawa Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, N. Tamura Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, N. Ichikawa Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, Y. Taniguchi Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, S. Tsuji Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, M. Okada Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, S. Kobayashi Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, T. Tomita Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None, M. Kishimoto Shareholder of: None, Grant/research support from: None, Consultant for: None, Employee of: None, Paid instructor for: None, Speakers bureau: None