AB0699 RESIDUAL DISEASE BURDEN PRESENT IN AXIAL SPONDYLOARTHRITIS AND PSORIATIC ARTHRITIS PATIENTS ACHIEVING LOW DISEASE ACTIVITY STATES
Authors: V. Liu, W. Fong, Y. H. Kwan, Y. Y. Leung
Journal: Annals of the Rheumatic Diseases (2020)

Background: Despite achieving Low Disease Activity (LDA) states, patients with SpondyloArthritis (SpA) may have considerable residual disease. Sparse data is currently available from Asia. Objectives: We aimed to evaluate the burden of residual disease in patients with axial SpondyloArthritis (axSpA) or Psoriatic Arthritis (PsA) who achieved LDA. Methods: We used data from a registry of SpA from an outpatient setting in a tertiary hospital in Singapore. For axSpA, LDA was defined as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) &lt;4/10. For PsA, LDA was defined by achieving 5/7 cutoffs in the Minimal Disease Activity (MDA) or clinical Disease Activity index for Psoriatic Arthritis (cDAPSA) ≤13. Results: From 262 cases of axSpA (21% women; mean ± standard deviation (SD) age 42 ± 14 years), 58% of patients achieved LDA states. While from 142 cases of PsA (49% women; mean ± SD age 51 ± 14 years), 38% and 63% achieved MDA and cDAPSA LDA, respectively. Both axSpA and PsA patients with LDA had pain scores range from 17.2 to 25.7/100 and fatigue scores from 3.3 to 3.5/10. (Table 1). Substantial burden in physical disability and mental well-being were seen as a low physical and mental component summary of SF-36. cDAPSA classified nearly twice as many PsA patients into LDA than MDA. Compared to PsA patients in MDA, PsA patients in cDAPSA LDA had higher pain scores, Patient Global Assessment (PtGA), dactylitis, and enthesitis. axSpA patients in LDA classified by BASDAI had the highest pain and fatigue scores, and PtGA. Table 1. Residual disease burden in patients with axSpA and PsA who have achieved LDA axSpA PsA LDA (n=153 ) LDA by MDA (n=54 ) LDA by cDAPSA (n=90 ) Age, years ¥ 42.2 (14.0) 52.5 (13.2) 52.5 (13.2) Female, n (%) 26 (17.0) 30 (55.6) 45 (50.0) TJC ¥ 0.1 (0.3) 0.8 (1.0) 1.0 (1.4) SJC ¥ 0.1 (0.3) 0.7 (1.3) 0.9 (1.3) VAS-pain (0-100) ¥ 25.7 (19.0) 17.2 (17.8) 20.8 (16.7) BASDAI (0-10) ¥ 2.3 (1.0) 2.4 (1.6) 2.7 (1.7) BASDAI fatigue (0-10) ¥ 3.5 (2.2) 3.3 (2.3) 3.4 (2.3) PtGA (0-100) ¥ 27.8 (19.5) 20.9 (17.9) 23.5 (17.6) Dactylitis (0-20) ¥ – 0.3 (0.5) 0.5 (0.9) LEI (0-6) ¥ – 0.1 (0.4) 0.2 (0.5) HAQ (0-3) ¥ 0.1 (0.1) 0.1 (0.2) 0.2 (0.4) HAQ &lt; 0.5, n (%) 149 (97.4) 52 (96.3) 77 (85.6) SF-36 PCS ¥ 46.8 (9.9) 45.8 (11.5) 45.1 (11.7) SF-36 MCS ¥ 46.4 (11.2) 46.1 (11.3) 45.6 (10.6) axSpA, axial Spondyloarthritis; PsA, Psoriatic Arthritis; LDA, Low Disease Activity; MDA, Minimal Disease Activity; cDAPSA, clinical Disease Activity index for Psoriatic Arthritis; TJC, tender joint count; SJC, swollen joint count; VAS, Visual Analog Scale; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; PtGA, patient’s global assessment; LEI, Leeds Enthesitis Index; HAQ, Health Assessment Questionnaire; SF-36, Short-Form 36; SF-36 PCS, norm-based Physical Component Summary (mean=50, SD=10); SF-36 MCS, norm-based Mental Component Summary (mean=50, SD=10) ¥ mean (SD) Conclusion: Despite being in LDA, axSpA and PsA patients experienced substantial pain, fatigue and poorer functional health and mental well-being. Disclosure of Interests: Venice Liu: None declared, Warren Fong Consultant of: Abbvie, Janssen, Novartis, Speakers bureau: Abbvie, Janssen, Novartis, Yu Heng Kwan: None declared, Ying Ying Leung Speakers bureau: Novartis, Janssen, Eli Lilly