POS0856 INCIDENCE, PREVALENCE AND MORTALITY OF EGPA: A SYSTEMATIC REVIEW AND META-ANALYSIS
Authors: J. Rowell, S. Lucas, M. Turner, P. Dolin
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare autoimmune disease characterised by vascular inflammation and multisystem organ damage. There is no commonly accepted set of diagnostic criteria for EGPA, with the Chapel Hill Consensus Conference definition, 1990 American College of Rheumatology (ACR) classification criteria and the 2022 ACR-EULAR classification criteria all used. In addition, International Classification of Diseases coding can be used to identify patients. A previous systematic review reported incidence and prevalence of EGPA with searches to June 2019; however, the recent introduction of biologics that target eosinophils may have an impact on diagnosis rates and outcomes. <h3>Objectives:</h3> To update and extend the systematic review of EGPA epidemiology. <h3>Methods:</h3> Searches were conducted in Ovid MEDLINE and Ovid Embase from January 2019 to June 2023 to provide the most recent data, without language restrictions. Relevant conferences and SLR bibliographies from 2020–2023 were hand searched. Risk of bias assessments on the main publication for each included full-text study were conducted with validated tools. This review has been registered with PROSPERO.[1] Frequentist meta-analyses were conducted using random effects models to generate pooled estimates for EGPA mortality, incidence and prevalence. <h3>Results:</h3> From a total of 1,815 records, 90 publications were included, which reported 69 unique studies. All-cause mortality was reported by 14 studies suitable for meta-analysis, and ranged from 0% to 17.6% across median follow-up times from three months to ten years. One database study reported 17.6% mortality in 767 patients with EGPA compared to 7.4% in age- and sex-matched controls, while a physician survey reported a 10-year mortality rate of 25% in patients with EGPA who are glucocorticoid dependent and 40% in patients with relapsed or refractory disease compared to 10% in the overall EGPA cohort. Prognostic factors with a statistically significantly increased risk of death included older age at onset, more severe and active disease and cardiac or cerebrovascular involvement (three studies). The pooled estimate for EGPA mortality was 10.63 per 1,000 person-years (95% confidence interval [CI]; 7.20, 15.71) (Figure 1A). Five studies reported incidence, ranging from 0.6 to 7.5 cases per million person-years. The pooled estimate for EGPA incidence was 2.03 cases per million person-years (95% CI; 0.97, 4.26 [Figure 1B]). Prevalence was reported by nine studies and ranged widely from 9.0 to 58.6 cases per million people. An increase in prevalence was observed over time (seven studies). The pooled estimate for EGPA prevalence was 34.44 per million people (95% CI; 22.92, 51.76 [Figure 1C]). <h3>Conclusion:</h3> The findings from this study are similar to previous reports [2] confirming that EGPA has a low incidence and prevalence, consistent with the rare nature of the disease. Data suggest that EGPA is more prevalent now compared to 5–10 years ago, which may reflect improved awareness, increased diagnosis and better treatment of the disease resulting in patients living longer. Reported mortality rates vary, but may be higher than the general population, particularly in patients who are glucocorticoid-dependent or with relapsed/refractory disease. <h3>REFERENCES:</h3> [1] National Institute for Health and Care Research. Epidemiology of eosinophilic granulomatosis with polyangiitis (EGPA): a systematic review (PROSPERO registration number: CRD42023432025). 2023. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=432025 [accessed 15 November 2023]. [2] Jakes RW, Kwon N, Nordstrom B, et al. Burden of illness associated with eosinophilic granulomatosis with polyangiitis: a systematic literature review and meta-analysis. Clin Rheumatol. 2021;40(12):4829-36. <h3>Acknowledgements:</h3> The authors thank Victoria Richardsdóttir Fife and Bianca Kennedy Hall from AstraZeneca for project support, and Sukhvir Rai and Kerrie Ford of Health Economics and Outcomes Research Ltd (Cardiff, UK) for medical writing support, which was funded by AstraZeneca (Cambridge, UK) in accordance with Good Publication Practice (GPP 2022) guidelines (https://www.ismpp.org/gpp-2022). <h3>Disclosure of Interests:</h3> Jennifer Rowell owns share options in AstraZeneca and Roche, employee of AstraZeneca, but previously employed by Roche, Amgen and QLT Phototherapeutics, Sara Lucas an employee of Health Economics and Outcomes Research Ltd. Health Economics and Outcomes Research Ltd. received funding for data analysis and medical writing support from AstraZeneca for this work, Matthew Turner an employee of Health Economics and Outcomes Research Ltd. Health Economics and Outcomes Research Ltd. received funding for data analysis and medical writing support from AstraZeneca for this work, Paul Dolin contractor for AstraZeneca.