AB0773 THE INCIDENCE OF RESIDUAL DISEASE ACTIVITY FOLLOWING DIVERSE DISEASE ACTIVITY MEASUREMENTS FOR PSORIATIC ARTHRITIS
Authors: H. H. Gezer, D. Erdem Gürsoy, S. Acer Kasman, M. T. Duruöz
Journal: Annals of the Rheumatic Diseases (2020)

Background: Due to the complex nature of psoriatic arthritis (PsA), diverse disease activity measures have been developed, the most common of which include Disease Activity Score for Psoriatic Arthritis (DAPSA), Minimal Disease Activity (MDA) and Very Low Disease Activity (VLDA). Recently, new composite measures have been developed such as Psoriatic Arthritis Disease Activity Score (PASDAS) and GRACE index. Due to different domains and assessments, even though these measures may indicate remission or low disease activity, residual disease activity (RDA) may persist. Objectives: The aim of this study was to evaluate RDA in patients with PsA. Methods: A total of 148 patients (105 female, 43 male; mean age 47.5 (SD:12.6) years) who met the CASPAR criteria for PsA were recruited. Demographic and clinical characteristics of patients were recorded, including pain visual analog scale (VAS), joint VAS, patient global VAS, and tender and swollen joint counts. Evaluations included the Leeds Enthesitis Index (LEI), Psoriasis Area and Severity Index (PASI), Psoriatic Arthritis Quality of Life (PsAQoL), Short-Form 36 Health Survey (SF-36) and Health Assesment Questionnaire (HAQ). Disease activity and remission were assessed using the DAPSA, MDA, VLDA, PASDAS and GRACE Index. MDA was calculated with 5 and 6 positivity criteria separately. Low disease activity (LDA) was defined as follows: DAPSA ≤ 14, PASDAS ≤ 3.2 and GRACE Index ≤ 2.3. RDA was defined as the presence of at least one of the following criteria despite remission or LDA: tender and/or swollen joints &gt;1, dactilitis &gt;1, LEI&gt;1, HAQ&gt;0.5, PASI&gt;1, PtGA&gt;20, physician VAS&gt;20, or pain VAS&gt;15. Results: The mean duration of disease was 68.2 (SD:80.2) months. DAPSA-LDA, PASDAS-LDA, GRACE-LDA, MDA and VLDA were observed in 48.6%, 14.6%, 14.9%, 23.6% and 2% of PsA patients, respectively. RDA as determined by at least one domain was identified in 91%, 95%, 86% and 86% of patients who were classified as having MDA, DAPSA-LDA, PASDAS-LDA and GRACE-LDA, respectively. Undetected RDA was most common with DAPSA, whereas VLDA completely ruled out RDA. PASDAS and GRACE resulted in similar rates of RDA (Table-1). With DAPSA-LDA, the incidence of RDA in the pain domain was significantly lower with older age. Female patients had higher rates of RDA with the LEI and HAQ (p&lt;0.05). Conclusion: VLDA was the most and DAPSA was the least sensitive method to detect remission/LDA. RDA should be kept in mind in patients with PsA when using current measures to assess remission or LDA. References: [1]Ennio Lubrano, Silvia Scriffignano, Fabio Massimo Perrotta, Residual disease activity and associated factors in Psoriatic Arthritis. The Journal of Rheumatology Nov 2019, jrheum. 190679; DOI: 10. 3899/jrheum.190679 [2]Kilic, G., Kilic, E., Nas, K. et al. Residual symptoms and disease burden among patients with psoriatic arthritis: is a new disease activity index required?. Rheumatol Int 39, 73–81 (2019). https://doi.org/10.1007/s00296-018-4201-3 Table 1. RDA in patients with LDA according to diverse activity scores RDA, n (%) Remission and LDA according to disease activity scores, n (%) MDA-5 n:35 MDA-6 n:13 VLDA n:3 DAPSA LDA n:72 PASDAS LDA n:22 GRACE LDA n:22 RDA_TJC 4 (11.4) 1 (7.7) 0 25 (34.7) 3 (13.6) 1 (4.5) RDA_SJC 1 (2.9) 0 0 3 (4.2) 0 0 RDA_dactilitis 2 (5.7) 0 0 2 (2.8) 1 (4.5) 1 (4.5) RDA_PASI 4 (11.4) 1 (7.7) 0 23 (31.9) 5 (22.7) 5 (22.7) RDA_VAS pain 23 (65.7) 3 (23.1) 0 56 (77.8) 13 (59.1) 13 (59.1) RDA_VAS Global 21 (60) 4 (30.8) 0 56 (77.8) 10 (45.5) 11 (50) RDA_physician VAS 26 (83.9) 8 (61.5) 1 (33.3) 64 (88.9) 15 (71.4) 16 (72.7) RDA_HAQ 1 (2.9) 1 (7.7) 0 16 (22.2) 1 (4.5) 0 RDA_LEI 1 (2.9) 1 (7.7) 0 24 (33.3) 3 (13.6) 2 (9.1) RDA: residual disease activity, MDA: Minimal disease activity, VLDA:Very Low disease activity, LDA: Low disease activity, TJC:Tender joint count, SJC: Swollen joint count Disclosure of Interests: None declared