Comparison of ankylosing spondylitis and non‐radiographic axial spondyloarthritis in a multi‐ethnic Asian population of Singapore

Abstract

Objectives:To compare clinical characteristics, disease activity, patient-reported outcomes and associated comorbidities between patients with ankylosing spondylitis (AS) and non-radiographic axial spondyloarthitis (nr-axSpA) in a multi-ethnic Asian population of Singapore. Methods: We used data from the PREcision medicine in SPONdyloarthritis forBetter Outcomes and Disease Remission (PRESPOND) registry in Singapore General Hospital. All patients fulfilled 2009 Assessment in AS International Working Group classification criteria for axial SpA (axSpA). Of these, all AS patients fulfilled the 1984 modified New York criteria. Baseline characteristics, medications, disease activity, patient-reported outcomes and inflammatory markers were recorded using standardized questionnaires.Results: Two hundred and sixty-two axSpA patients (82% Chinese, 79% male) were included. Mean age (SD) at diagnosis was 32.4 (13.1) years, which was similar between AS and nr-axSpA patients. AS patients were older (mean age 42.7 [13.5] vs 37.4 [13.8] years, P = 0.02), had longer disease duration (mean disease duration 10.9 [8.7] vs 6.4 [4.8] years, P < 0.01), higher Bath Ankylosing Spondylitis Metrology Index (BASMI) (mean BASMI 3.1 [2.3] vs 1.5 [1.5], P < 0.01), more frequently human leukocyte antigen (HLA)-B27 positive (82% vs 68%, P = 0.03), associated with uveitis (33% vs 17%, P = 0.03), and hypertensive (17% vs 0%, P < 0.01) compared to nr-axSpA, respectively. Nr-axSpA patients had higher Bath Ankylosing Spondylitis Global Score (BAS-G) (mean BAS-G 46.9 [16.8] vs 38.6 [20.6], P < 0.01), Bath Ankylosing Spondylitis Disease Activity Index (mean [SD] 4.2 [1.6] vs 3.5 [1.9], P = 0.02) and AS quality of life (ASQoL) (mean ASQoL 4.9 [4.8] vs 3.5 [4.1], P = 0.04) scores compared to AS patients respectively at baseline. Patient global assessment, Bath Ankylosing Spondylitis Functional Index, AS Disease Activity Score -C-reactive protein (CRP), Health Assessment Questionnaire, Short-Form 36 physical component summary and How to cite this article: Hong C, Kwan YH, Leung Y-Y, Lui NL, Fong W. Comparison of ankylosing spondylitis and nonradiographic axial spondyloarthritis in a multi-ethnic Asian population of Singapore. Int J Rheum Dis. 2019;22:1506-1511. https ://doi.

Residual Disease Burden in Patients With Axial Spondyloarthritis and Psoriatic Arthritis Despite Low Disease Activity States in a Multiethnic Asian Population

“…A total of 262 patients with axSpA (21% women; mean ± SD age 42 ± 14 yrs) and 142 patients with PsA (49% women; mean ± SD age 51 ± 14 yrs) were analyzed in this study (Table 1). As previously reported, patients with axSpA had long disease duration, with 82% fulfilling radiographic sacroiliitis criteria 13 . Compared to patients with PsA, patients with axSpA were younger and more likely to be men.…”

“…Study design. We used the cross-sectional baseline data of the PREcision medicine in SPondyloarthritis for better Outcomes aND Disease remission registry 10,12,13 from a tertiary rheumatology center in Singapore General Hospital from 2012 to 2018.…”

Role of Metrology in Axial Spondyloarthritis: Does It Provide Unique Information in Assessing Patients and Predicting Outcome? Results From the British Society for Rheumatology Biologic Register for Ankylosing Spondylitis

“…However, these issues would make estimating the BASMI score more difficult, and the data would underestimate the performance of a model to do so. Participants in the data set predominantly fulfilled the mNY criteria with established radiographic changes (68%); thus, the presented model might be different in a cohort with more nonradiographic axial SpA participants, as the BASMI scores appear to be lower in this population (34). Whenever there are missing data, a possibility of selection bias exists.…”

“…The BSRBR-AS registry comprises a relatively large cohort of participants compared to other studies assessing BASMI in the scientific literature (34)(35)(36)(37)(38)(39). Most patients seen in rheumatology clinics would have been eligible and recruiting centres included teaching and district general hospitals covering wide geographic areas.…”

“…Participants in the dataset predominantly fulfilled the mNY criteria with established x-ray changes (68%), thus, the presented model might be different in a cohort with more non-radiographic axSpA participants, as BASMI scores appear to be lower in this population (34). Whenever there is missing data, there is the possibility of selection bias.…”