AB0351 ELDERLY-ONSET RHEUMATOID ARTHRITIS (EORA): DIFFERENCES ACCORDING TO CLINICAL DEBUT AND SEROLOGICAL POSITIVITY
Authors: María Andreína Terán Tinedo, Cristina Pijoan Moratalla, Jose Renato Quiñones Torres
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> In patients with Elderly-onset Rheumatoid Arthritis (EORA) has been described a clinical debut mimicking polymyalgia rheumatica with rhizomelic <i>pseudopolyarthritis,</i> in contrast with the classical profile of patients with Rheumatoid Arthritis similar to younger patients. We compare in our study these two profiles of the disease. <h3>Objectives</h3> To describe and compare the differences according to clinical debut, serological positivity and its implications in terms of treatment and prognostic factors in patients with Elderly-onset Rheumatoid Arthritis (EORA). <h3>Methods</h3> Patients with a diagnosis of RA over 65 years of age according to ACR/EULAR 2010 criteria were included. A database was created including the age of onset, the presence of polymyalgia-like symptoms (<i>rhizomelic pseudopolyarthritis</i>), the positivity of rheumatoid factor (RF) and anti-c<i>itrullinated</i> protein <i>antibodies</i> (ACPAs), elevation of acute phase reactants (APR), the presence of erosions and the treatment required. Finally, data was analyzed according to clinical debut, serological positivity and prognostic factors. <h3>Results</h3> 83 patients diagnosed of EORA were included, with an average age of 73.8 years. 71.25% had positive RF (58.75% high titers) and 62.5% had positive ACPA (52.3% high titers). 24/83 patients (29%) debuted with a polymyalgia-like symptoms. 47.5% had persistent APR elevation during follow-up. Regarding treatment, 15% were treated only with corticosteroids, 81.5% required treatment with DMARDs and 15% were receiving biological treatment. 42/83 patients (50%) had erosions on plain X-rays. Of those patients with a polymyalgia-like profile, 52.2% (43/83) had positive RF but most of them had low titers (61%). On the other hand, patients without polymyalgia-like symptoms had positive RF in 78% of the cases and most of them at high titers (66%, p = 0.01). In the first group there was less positivity for ACPAs (26%, p = 0.00004) and half of them had low titers. Erosions were observed in only 30% of the patients with polymyalgia-like symptoms, while those without this profile had more erosions (58%, p = 0.02) and higher APR (50%, p = 0.026). Regarding treatment, in the group with polymyalgia-like symptoms only 34% were treated with corticosteroids, 65% required DMARDs and no patients had received biological treatment, whereas in the non-polymyalgic group, 88% required DMARDs and 21% required biologics (p = 0.01 for both results). Analyzing patients with positive RF and ACPAs at high titers, 93% received treatment with DMARDs and 24% required biological treatment. 65% had persistent elevation of APR and 48% presented erosions on plain X- rays. Only 2 patients with positive RF and ACPAs at high titers debuted with a polymyalgia-like symptoms. <h3>Conclusion</h3> Patients with EORA with polymyalgia-like symptoms tend to have less erosions and a higher prevalence of negative RF and ACPA or at low titers. These patients usually require less DMARDs and biological treatments to control the disease unlike patients with non-polymyalgia symptoms. On the other hand, patients with high RF and ACPA titers have more erosions and elevated APR during follow-up but do not usually experience polymyalgia-like symptoms. <h3>Reference</h3> [1] Tutuncu Z, Reed G, Kremer J, Kavanaugh A. Do patients with older-onset rheumatoid arthritis receive less aggressive treatment?. Ann Rheum Dis. 2006;65(9):1226-9. <h3>Disclosure of Interests</h3> None declared