OP0180 Risk of Developing Clinical Synovitis in ACPA Positive Patients with Non-Specific Musculoskeletal Symptoms
Authors: C. Rakieh, J. L. Nam, L. Hunt, E. Villeneuve, L.-A. Bissell, S. Das, P. G. Conaghan, D. McGonagle, R. J. Wakefield, P. Emery
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> Rheumatoid Arthritis (RA) is associated with autoantibodies including ACPA which may be present years before clinical presentation. In the pre clinical phase, patients usually present with non specific musculoskeletal (MSK) symptoms. <h3>Objectives</h3> 1- To monitor the progression In ACPA positive patients with non specific MSK symptoms to clinical synovitis (CS). 2- To investigate if demographic, clinical, imaging, and serological measures can identify patients at high risk of developing RA at pre-clinical stage. <h3>Methods</h3> Patients were recruited from rheumatology clinics and primary care. Clinical assessment and investigations including magnetic resonance imaging (MRI) and ultrasound (US) were undertaken at baseline and 3-6 month intervals or at change of symptoms. The end point was the development of CS, defined as the presence of at least one tender and swollen joint. Healthy controls were recruited as a comparator group. <h3>Results</h3> A total of 122 patients without a diagnosis of inflammatory arthritis were studied. 22 patients were found to have CS at baseline and hence were excluded from analysis. 100 patients (73% females) with a mean age of 51 years (±11.8) had no CS at baseline and were followed up for a median duration of 38.5 weeks (range 1-234 weeks). 44 patients (44%) developed CS after a median duration of 26.5 weeks (1-170 weeks); 22 patients (22%) within 6 months and 33 (33%) within 12 months. Baseline early morning stiffness (EMS) was the only clinical parameter which demonstrated significant difference between the two groups; 59 minutes in those who progressed and 19 minutes in those who did not (P=0.001). The remaining baseline demographic, clinical, and serological parameters were not significantly different between the two groups. Baseline US of wrist and hands (controls =28, patients=98) showed a mean total power Doppler (PD) of 0.2 (SD 0.5) in the controls. In patients who did not progress, mean total PD score was 0.8 (SD 1.8) compared to 2.0 (SD 3.0) in those who progressed (p=0.003). A sub group of ACPA positive patients underwent MRI of a wrist and hand (n=33). Significant difference in flexor tenosynovitis mean score was demonstrated between groups (1.8 (SD 1.6) in patients who progressed vs. 0.7 (SD 1.1) in those with no progression, p=0.024). <h3>Conclusions</h3> A significant proportion of patients in this cohort progressed to clinical synovitis, the majority within 12 months of presentation. EMS was the only clinical parameter associated with progression. US and MRI may provide a useful tool in identifying patients who may progress to CS. <h3>Disclosure of Interest</h3> C. Rakieh: None Declared, J. Nam: None Declared, L. Hunt: None Declared, E. Villeneuve: None Declared, L.-A. Bissell: None Declared, S. Das: None Declared, P. Conaghan: None Declared, D. McGonagle: None Declared, R. Wakefield: None Declared, P. Emery Consultant for: Honoraria/Advisory Board: Abbot, Pfizer, Roche, Chugai, BMS, UCB, MSD