AB0677 Comparative Characteristics of Radiographic and Non-Radiographic Axial Spondyloarthritis (NR-AXSPA) Based on Data from 12 Month Follow Up of Corsar Cohort: Table 1

Abstract

BackgroundClinical similarity of nr-axSpA and ankylosing spondylitis (AS) has been well established, but whether nr-axSpA is an initial stage of AS, or these two subtypes are nosologically self-determined entities is still being debated.ObjectivesTo study the evolution of early axial spondyloarthritis (axSpA) in the Moscow axSpA cohort of patients (pts) - CoRSaR (Russian acronym from CohoRt of early axSpA pts).MethodsCurrently the CoRSaR cohort includes 94 axSpA pts with <5 years of inflammatory back pain duration (ASAS 2009y.criteria). 54 out of them with at least 12 months (mo) follow up pts (FUP) were included into preliminary analysis of axSpA evolution study. Evaluation of all pts at inclusion (Mo0) and FUP (Mo12) visits was similar and included: medical case history, clinical examination, X-ray of pelvis (and other segments of the back bone and joints, when necessary) - following ASAS guidelines, MRI of sacroiliac joints. Pts' mean age at Mo0 visit was 27,1±5,5 y., average disease duration - 22,4±15,1 mo, 49 (90,7%) pts were HLA-B27 positive.ResultsPts were grouped into 2 arms to analyze axSpA evolution: Group 1 – nr-axSpA, Group 2 – AS. The table shows pts' baseline and FUP Mo12 visit characteristics. No significant difference has been found between the two groups – radiographic AS and nr-axSpA - in terms of prevalence of arthritis, enthesitis, BASDAI, ASDAS CRP, and BASFI scores. Radiographic sacroiliitis, i.e., AS, has developed in 9 (39%) out of 23 nr-axSpA pts during 12 Mo FUP.Table 1Mo0 visit (n=54)FUP Mo12 visit (n=54)ASNr-axSpAASNr-axSpApn=31 (57.4%)n=23 (42.6%)n=40 (74.0%)n=14 (26.0%)Gender: m, % / f ,%17 (54.8%) / 14 (45.2%)7 (30.4%) / 16 (69.6%)0.0720 (50.0%) / 20 (50.0%)4 (28.5%) / 10 (71.5%)0.16BASDAI score, Me [25%;75%]3.4 [1.6; 5.1]3.5 [2.0; 4.9]0.831.8 [0.80; 3.65]2.75 [1.2; 3.6]0.57BASFI score, Me [25%;75%]1.2 [0.3; 2.5]1.4 [0.3; 2.5]0.830.65 [0; 2.05]0.35 [0.1; 1.3]0.77ASDAS-CRP score, Me [25%;75%]2.5 [1.4; 3.1]1.8 [1.3; 3.1]0.41.35 [1.1; 2.05]1.3 [1.0; 2.1]0.78CRP, mg/L, Me [25%;75%]4.3 [1.0; 20.0]4.8 [0.6; 9.7]1.02.3 [0.85; 10.1]2.5 [0.8; 4.8]0.78ESR, mm/h, Me [25%;75%]13.0 [5.0; 24.0]8.0 [5.0; 14.0]0.47.5 [5.0; 21.0]6.5 [5.0; 8.0]0.38MASES score, Me [25%;75%]1.0 [0.0; 2.0]1.0 [0; 3.0]0.810 [0; 1.0]0 [0; 0]1.0SJC, Me [25%; 75%]0.0 [0; 0]0.0 [0; 0]0.288840 [0; 0]0 [0; 0]0.00000ConclusionsNo clinical differences between radiologically confirmed axSpA (i.e., AS) and nr-axSpA were established. AS has developed in 9 (39%) out of 23 nr-axSpA pts during 12 Mo.Disclosure of InterestNone declared