OP0153 Resolution of symptoms of patients with clinically suspect arthralgia is paralleled by disappearance of mri-detected subclinical inflammation; a longitudinal study
Authors: R.M. Ten Brinck, D.M. Boeters, H.W. van Steenbergen, A.H. van der Helm– van Mil
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> It is known that MRI-detected subclinical inflammation in patients with Clinically Suspect Arthralgia (CSA) precedes the development of clinically evident Inflammatory Arthritis (IA). However, there are no longitudinal studies in CSA patients that did not progress to IA. The course of joint symptoms in these patients is unknown. Furthermore, it is unknown if subclinical inflammation resolves spontaneously in parallel with disappearance of joint symptoms. <h3>Objectives</h3> To determine the course of joint symptoms and of MRI-detected subclinical joint inflammation, and mutual time relationships, in patients that presented with CSA but did not progress to IA during 2 year follow-up. <h3>Methods</h3> Between April 2012-April 2014, 149 patients were included in the CSA cohort. These patients had no clinically evident arthritis but recent-onset (&lt;1 year) arthralgia of small joints that was clinically considered at risk for IA by the rheumatologist. None of the patients were treated with DMARDs. Patients underwent MRI at baseline and when arthritis developed or after 2 years (when follow-up ended). The patients that did not progress to IA within 2 years and had serial MRIs, as well as longitudinal clinical data and questionnaires (e.g. the HAQ), were studied (n=60). 1.5T MRIs of wrist, MCP2–5, and MTP1–5 joints were scored for synovitis, tenosynovitis and bone marrow oedema (BME) (summed in the total MRI inflammation score) according to RAMRIS, blinded for order in time and clinical information. Paired t-tests were used. <h3>Results</h3> After 2 year follow-up, 20 patients (33%) had complete resolution of symptoms whereas 40 patients (66%) did not. The remaining symptoms in the latter group were diagnosed as: persistent inflammatory arthralgia (n=26), osteoarthritis (n=6) and tendinomyalgia (n=8). In the total group, the mean total MRI-inflammation score decreased from 3.2 at baseline to 2.5 at 2 years (p=0.046). When the patients with persistent symptoms were studied, there were no significant changes in MRI-inflammation scores. Analysing the patients with resolution of symptoms separately, the total MRI-inflammation score decreased significantly (3.3 to 2.3; p=0.019). Also the total synovitis and tenosynovitis scores decreased significantly (1.3 to 0.82 and 0.83 to 0.30, respectively; p=0.043 and p=0.029), whereas BME scores remained unchanged (1.2 and 1.2; p=0.87). After 2 year follow-up the absolute MR-scores of these patients were compared to data from age-matched symptom-free controls; no differences were found for synovitis, suggesting normalisation. Physical functioning, measured with HAQ, remained similar in patients with persistent symptoms (0.56 to 0.51; p=0.61), whereas HAQ normalised in patients with resolution of symptoms (mean score of 0.15 at 2 years, p=0.053 compared to baseline). <h3>Conclusions</h3> Approximately one-third of the patients that presented with CSA and that did not convert to IA had resolution of symptoms, this was paralleled by normalisation of MRI-detected inflammation as well as physical functioning. This is the first study showing that subclinical inflammation in individuals at risk for developing RA can resolve spontaneously. The data suggest that subclinical inflammation was causally related to joint pain. <h3>Disclosure of Interest</h3> None declared