THU0286 Predictors for orthopaedic surgery in patients with psoriatic arthritis. results from a retrospective cohort study of 590 patients diagnosed 1954–2011, and followed up until 2017
Authors: T.W. Nystad, Y. Husum, O.N. Furnes, B.T.S. Fevang
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Psoriatic arthritis with peripheral joint affection is a progressive disease in most patients, and erosions are seen in 47% within the first two years.<sup><sup>1</sup></sup> Synthetic disease modifying anti rheumatic drugs (DMARDs) are generally prescribed, to inhibit inflammation, but have not been proven to slow or prevent radiographic changes. Biologic treatment is recommended when other agents are not efficient, and has been shown to give better control of structural damage.<sup><sup>2</sup></sup> Orthopaedic corrective surgery has been a necessary part of treating patients with psoriatic arthritis, when medication fails to prevent joint destruction. Surgery can be considered a proxy for joint damage, and studying time trends in orthopaedic surgery thus gives valuable information regarding the prognosis of patients with inflammatory arthritis. In patients with rheumatoid arthritis there has, over time, been a declining incidence of orthopaedic interventions. The change in available medical treatment is believed to be responsible for this.<sup><sup>3</sup></sup> As synthetic DMARDs may be less efficient in patients with psoriatic arthritis, it is uncertain whether a decline of the same magnitude can be expected among these patients. <h3>Objectives</h3> We wished to investigate trends in the incidence of orthopaedic procedures in patients with psoriatic arthritis, and to explore how patient characteristics, time of diagnosis and treatment affect the need for surgery. <h3>Methods</h3> We reviewed the medical history of 1432 patients with possible psoriatic arthritis at Haukeland University Hospital in Bergen, Norway from 1954–2011, of which 590 (mean age 49, 52% women) had a confirmed diagnosis of psoriatic arthritis, and sufficient journal information, and were included in the present study. Relevant orthopaedic procedures were obtained from the Norwegian Arthroplasty Register and the hospital's administrative patient records. 171 procedures (25% joint synovectomies, 15% arthrodeses and 53% prostheses) were performed in 117 patients. Survival analyses were completed to evaluate the impact of different factors such as year of diagnosis, age, sex, radiographic changes, disease activity and treatment, on the risk of undergoing surgery. <h3>Results</h3> Female sex, older age (≥70) and maximum ESR 30–59 significantly increased the risk of surgery whereas time period of diagnosis had no effect on the outcome. Anti-rheumatic treatment changed significantly over time. <h3>Conclusions</h3> 20% of patients with psoriatic arthritis needed surgery during disease course. In our material, the prognosis of patients with psoriatic arthritis has not changed, with regard to the risk of orthopaedic surgery, despite significant changes in treatment. This is contrary to what is seen for patients with rheumatoid arthritis. <h3>References</h3> [1] Kane D, et al. PMID 14523223 [2] Mease PJ, et al. PMID 26476229 [3] Nystad TW, et al. PMID 26303149 <h3>Disclosure of Interest</h3> None declared