Pos0411 Characteristics at Diagnosis Associated to Glucocorticoid Use at 2 Years for Those With Polymyalgia Rheumatica - A National Study of England

Background: Current guidelines recommend glucocorticoids (GCs) for the treatment of Polymyalgia Rheumatica (PMR) for 1 to 2 years. Surveys and administrative datasets from many European countries and the USA show that approximately 50% of patients are on GCs for at least 2 years. A previous study looking at individuals with PMR and GC dependence, found the neutrophil-lymphocyte ratio (NLR) at diagnosis to be associated with GC dependency. Objectives: To understand baseline factors and patient characteristics associated with continuing GCs at two years. Methods: Prescribing Services Limited (PSL) gained NHS Digital central assurance in 2017 and processes NHS data for 27 million people living in England, carrying out risk stratification for unplanned admission though the ECLIPSE Live system. We used de-identified data for patients not opted out of use of data for service development and research identifying all patients with a diagnosis of PMR between 1st Jan 2016 to 19th July 2021 and, linking to prescribing data, applied a previously used Clinical Practice Research Datalink (CPRD) definition of PMR (diagnosis of PMR, with issue of GCs within 6 months of diagnosis date and second prescription within 6 months of the first). Patient characteristics including blood test results were analysed using logistic regression to ascertain associations to GC prescription, with at least 2 years of follow-up. Results: There were 39,460 individuals with PMR who fulfilled these criteria; of these 22 were under the age of 40 years and excluded from analysis. The median age at diagnosis was 73.7 yrs (IQR 67.7 to 79.2 yrs), and 61.4% female. The median C-reactive protein (CRP) at diagnosis was 26 mg/L (IQR 11 to 53 mg/L), with 85.9% having a CRP of 6 mg/L or more, and 32.5% were anaemic at the time of diagnosis. The median NLR and platelet-to-lymphocyte (PLR) ratio was 3.36 (IQR 2.40 to 4.69) and 184 (IQR 137 to 248) respectively. GC prescription was assessed in 3-monthly brackets, observing those that managed to stay within a cumulative steroid exposure as recommended by the current BSR guidelines and those who were no longer prescribed steroids (See Table 1). Table 1. *The CPRD definition allowed individuals to start GCs within six months of diagnosis date and a second prescription within six months of the first prescription Logistic regression was carried out to assess factors associated with continuing GCs at 24 months. The multivariable model found an older age and higher initial steroid use were associated with lower probability of remaining on GCs, while females, smokers, those with anaemia, and a higher CRP and PLR were more likely to remain on steroids (see Table 2). Table 2. Conclusion: This is the largest study to assess baseline characteristics and their association to continuing GCs at 2 years. This community-based study of real-world evidence shows 86% have a raised CRP at diagnosis and is reflective of the demographic of what is expected for those diagnosed with PMR. Several baseline characteristics are associated with outcome at 2 years and exceeding the cumulative GCs dose in the first 3 months may allow individuals to come off steroids within 2 years. Replication of this study to other countries is of interest to inform GC tapering strategies. REFERENCES: 1 BSR guidelines for the management of Polymyalgia Rheumatica. Dasgupta et al. (2010) Rheumatology Oxford. 2 Incidence of diagnosed polymyalgia rheumatica and temporal arteritis in the United Kingdom, 1990-2001 Smeeth et al. (2006), Annals of Rheumatic Disease. 3 Neutrophil to lymphocyte ratio predicts glucocorticoid resistance in Polymyalgia Rheumatica. (2020) Owen et al. International Journal Rheumatic Disease. Acknowledgements: NIL. Disclosure of Interests: Max Yates Advisory Board for BioGen and Galapagos, Pratyasha Saha: None declared, Clare Aldus: None declared, Julian Brown: None declared, Alex MacGregor: None declared.